diff --git a/cache/cache_test.cc b/cache/cache_test.cc index 1a8bae4df..75c28c2b8 100644 --- a/cache/cache_test.cc +++ b/cache/cache_test.cc @@ -1023,21 +1023,21 @@ TEST_P(CacheTest, DefaultShardBits) { (GetParam() == kHyperClock ? 32U * 1024U : 512U) * 1024U; std::shared_ptr cache = NewCache(32U * min_shard_size); - ShardedCache* sc = dynamic_cast(cache.get()); + ShardedCacheBase* sc = dynamic_cast(cache.get()); ASSERT_EQ(5, sc->GetNumShardBits()); cache = NewCache(min_shard_size / 1000U * 999U); - sc = dynamic_cast(cache.get()); + sc = dynamic_cast(cache.get()); ASSERT_EQ(0, sc->GetNumShardBits()); cache = NewCache(3U * 1024U * 1024U * 1024U); - sc = dynamic_cast(cache.get()); + sc = dynamic_cast(cache.get()); // current maximum of 6 ASSERT_EQ(6, sc->GetNumShardBits()); if constexpr (sizeof(size_t) > 4) { cache = NewCache(128U * min_shard_size); - sc = dynamic_cast(cache.get()); + sc = dynamic_cast(cache.get()); // current maximum of 6 ASSERT_EQ(6, sc->GetNumShardBits()); } diff --git a/cache/clock_cache.cc b/cache/clock_cache.cc index 58a7f94bb..d353c9966 100644 --- a/cache/clock_cache.cc +++ b/cache/clock_cache.cc @@ -12,6 +12,7 @@ #include #include +#include "cache/cache_key.h" #include "monitoring/perf_context_imp.h" #include "monitoring/statistics.h" #include "port/lang.h" @@ -29,16 +30,22 @@ inline uint64_t GetRefcount(uint64_t meta) { ClockHandle::kCounterMask; } +void ClockHandleBasicData::FreeData() const { + if (deleter) { + UniqueId64x2 unhashed; + (*deleter)(ClockCacheShard::ReverseHash(hashed_key, &unhashed), value); + } +} + static_assert(sizeof(ClockHandle) == 64U, "Expecting size / alignment with common cache line size"); ClockHandleTable::ClockHandleTable(int hash_bits, bool initial_charge_metadata) : length_bits_(hash_bits), - length_bits_mask_(Lower32of64((uint64_t{1} << length_bits_) - 1)), - occupancy_limit_(static_cast((uint64_t{1} << length_bits_) * - kStrictLoadFactor)), + length_bits_mask_((size_t{1} << length_bits_) - 1), + occupancy_limit_(static_cast((uint64_t{1} << length_bits_) * + kStrictLoadFactor)), array_(new ClockHandle[size_t{1} << length_bits_]) { - assert(hash_bits <= 32); // FIXME: ensure no overlap with sharding bits if (initial_charge_metadata) { usage_ += size_t{GetTableSize()} * sizeof(ClockHandle); } @@ -47,7 +54,7 @@ ClockHandleTable::ClockHandleTable(int hash_bits, bool initial_charge_metadata) ClockHandleTable::~ClockHandleTable() { // Assumes there are no references or active operations on any slot/element // in the table. - for (uint32_t i = 0; i < GetTableSize(); i++) { + for (size_t i = 0; i < GetTableSize(); i++) { ClockHandle& h = array_[i]; switch (h.meta >> ClockHandle::kStateShift) { case ClockHandle::kStateEmpty: @@ -58,7 +65,7 @@ ClockHandleTable::~ClockHandleTable() { assert(GetRefcount(h.meta) == 0); h.FreeData(); #ifndef NDEBUG - Rollback(h.hash, &h); + Rollback(h.hashed_key, &h); usage_.fetch_sub(h.total_charge, std::memory_order_relaxed); occupancy_.fetch_sub(1U, std::memory_order_relaxed); #endif @@ -71,7 +78,7 @@ ClockHandleTable::~ClockHandleTable() { } #ifndef NDEBUG - for (uint32_t i = 0; i < GetTableSize(); i++) { + for (size_t i = 0; i < GetTableSize(); i++) { assert(array_[i].displacements.load() == 0); } #endif @@ -154,12 +161,12 @@ inline void CorrectNearOverflow(uint64_t old_meta, } } -Status ClockHandleTable::Insert(const ClockHandleMoreData& proto, +Status ClockHandleTable::Insert(const ClockHandleBasicData& proto, ClockHandle** handle, Cache::Priority priority, size_t capacity, bool strict_capacity_limit) { // Do we have the available occupancy? Optimistically assume we do // and deal with it if we don't. - uint32_t old_occupancy = occupancy_.fetch_add(1, std::memory_order_acquire); + size_t old_occupancy = occupancy_.fetch_add(1, std::memory_order_acquire); auto revert_occupancy_fn = [&]() { occupancy_.fetch_sub(1, std::memory_order_relaxed); }; @@ -198,7 +205,7 @@ Status ClockHandleTable::Insert(const ClockHandleMoreData& proto, } if (request_evict_charge > 0) { size_t evicted_charge = 0; - uint32_t evicted_count = 0; + size_t evicted_count = 0; Evict(request_evict_charge, &evicted_charge, &evicted_count); occupancy_.fetch_sub(evicted_count, std::memory_order_release); if (LIKELY(evicted_charge > need_evict_charge)) { @@ -263,7 +270,7 @@ Status ClockHandleTable::Insert(const ClockHandleMoreData& proto, need_evict_charge = 1; } size_t evicted_charge = 0; - uint32_t evicted_count = 0; + size_t evicted_count = 0; if (need_evict_charge > 0) { Evict(need_evict_charge, &evicted_charge, &evicted_count); // Deal with potential occupancy deficit @@ -323,9 +330,9 @@ Status ClockHandleTable::Insert(const ClockHandleMoreData& proto, } assert(initial_countdown > 0); - uint32_t probe = 0; + size_t probe = 0; ClockHandle* e = FindSlot( - proto.hash, + proto.hashed_key, [&](ClockHandle* h) { // Optimistically transition the slot from "empty" to // "under construction" (no effect on other states) @@ -338,7 +345,7 @@ Status ClockHandleTable::Insert(const ClockHandleMoreData& proto, if (old_state == ClockHandle::kStateEmpty) { // We've started inserting into an available slot, and taken // ownership Save data fields - ClockHandleMoreData* h_alias = h; + ClockHandleBasicData* h_alias = h; *h_alias = proto; // Transition from "under construction" state to "visible" state @@ -375,7 +382,7 @@ Status ClockHandleTable::Insert(const ClockHandleMoreData& proto, if ((old_meta >> ClockHandle::kStateShift) == ClockHandle::kStateVisible) { // Acquired a read reference - if (h->key == proto.key) { + if (h->hashed_key == proto.hashed_key) { // Match. Release in a way that boosts the clock state old_meta = h->meta.fetch_add( ClockHandle::kReleaseIncrement * initial_countdown, @@ -431,7 +438,7 @@ Status ClockHandleTable::Insert(const ClockHandleMoreData& proto, return Status::OK(); } // Roll back table insertion - Rollback(proto.hash, e); + Rollback(proto.hashed_key, e); revert_occupancy_fn(); // Maybe fall back on detached insert if (handle == nullptr) { @@ -446,7 +453,7 @@ Status ClockHandleTable::Insert(const ClockHandleMoreData& proto, assert(use_detached_insert); ClockHandle* h = new ClockHandle(); - ClockHandleMoreData* h_alias = h; + ClockHandleBasicData* h_alias = h; *h_alias = proto; h->detached = true; // Single reference (detached entries only created if returning a refed @@ -467,10 +474,10 @@ Status ClockHandleTable::Insert(const ClockHandleMoreData& proto, return Status::OkOverwritten(); } -ClockHandle* ClockHandleTable::Lookup(const CacheKeyBytes& key, uint32_t hash) { - uint32_t probe = 0; +ClockHandle* ClockHandleTable::Lookup(const UniqueId64x2& hashed_key) { + size_t probe = 0; ClockHandle* e = FindSlot( - hash, + hashed_key, [&](ClockHandle* h) { // Mostly branch-free version (similar performance) /* @@ -501,7 +508,7 @@ ClockHandle* ClockHandleTable::Lookup(const CacheKeyBytes& key, uint32_t hash) { if ((old_meta >> ClockHandle::kStateShift) == ClockHandle::kStateVisible) { // Acquired a read reference - if (h->key == key) { + if (h->hashed_key == hashed_key) { // Match return true; } else { @@ -596,7 +603,7 @@ bool ClockHandleTable::Release(ClockHandle* h, bool useful, delete h; detached_usage_.fetch_sub(total_charge, std::memory_order_relaxed); } else { - uint32_t hash = h->hash; + UniqueId64x2 hashed_key = h->hashed_key; #ifndef NDEBUG // Mark slot as empty, with assertion old_meta = h->meta.exchange(0, std::memory_order_release); @@ -607,7 +614,7 @@ bool ClockHandleTable::Release(ClockHandle* h, bool useful, h->meta.store(0, std::memory_order_release); #endif occupancy_.fetch_sub(1U, std::memory_order_release); - Rollback(hash, h); + Rollback(hashed_key, h); } usage_.fetch_sub(total_charge, std::memory_order_relaxed); assert(usage_.load(std::memory_order_relaxed) < SIZE_MAX / 2); @@ -654,10 +661,10 @@ void ClockHandleTable::TEST_ReleaseN(ClockHandle* h, size_t n) { } } -void ClockHandleTable::Erase(const CacheKeyBytes& key, uint32_t hash) { - uint32_t probe = 0; +void ClockHandleTable::Erase(const UniqueId64x2& hashed_key) { + size_t probe = 0; (void)FindSlot( - hash, + hashed_key, [&](ClockHandle* h) { // Could be multiple entries in rare cases. Erase them all. // Optimistically increment acquire counter @@ -667,7 +674,7 @@ void ClockHandleTable::Erase(const CacheKeyBytes& key, uint32_t hash) { if ((old_meta >> ClockHandle::kStateShift) == ClockHandle::kStateVisible) { // Acquired a read reference - if (h->key == key) { + if (h->hashed_key == hashed_key) { // Match. Set invisible. old_meta = h->meta.fetch_and(~(uint64_t{ClockHandle::kStateVisibleBit} @@ -691,7 +698,7 @@ void ClockHandleTable::Erase(const CacheKeyBytes& key, uint32_t hash) { << ClockHandle::kStateShift, std::memory_order_acq_rel)) { // Took ownership - assert(hash == h->hash); + assert(hashed_key == h->hashed_key); // TODO? Delay freeing? h->FreeData(); usage_.fetch_sub(h->total_charge, std::memory_order_relaxed); @@ -706,7 +713,7 @@ void ClockHandleTable::Erase(const CacheKeyBytes& key, uint32_t hash) { h->meta.store(0, std::memory_order_release); #endif occupancy_.fetch_sub(1U, std::memory_order_release); - Rollback(hash, h); + Rollback(hashed_key, h); break; } } @@ -735,14 +742,14 @@ void ClockHandleTable::Erase(const CacheKeyBytes& key, uint32_t hash) { } void ClockHandleTable::ConstApplyToEntriesRange( - std::function func, uint32_t index_begin, - uint32_t index_end, bool apply_if_will_be_deleted) const { + std::function func, size_t index_begin, + size_t index_end, bool apply_if_will_be_deleted) const { uint64_t check_state_mask = ClockHandle::kStateShareableBit; if (!apply_if_will_be_deleted) { check_state_mask |= ClockHandle::kStateVisibleBit; } - for (uint32_t i = index_begin; i < index_end; i++) { + for (size_t i = index_begin; i < index_end; i++) { ClockHandle& h = array_[i]; // Note: to avoid using compare_exchange, we have to be extra careful. @@ -776,7 +783,7 @@ void ClockHandleTable::ConstApplyToEntriesRange( } void ClockHandleTable::EraseUnRefEntries() { - for (uint32_t i = 0; i <= this->length_bits_mask_; i++) { + for (size_t i = 0; i <= this->length_bits_mask_; i++) { ClockHandle& h = array_[i]; uint64_t old_meta = h.meta.load(std::memory_order_relaxed); @@ -788,7 +795,7 @@ void ClockHandleTable::EraseUnRefEntries() { << ClockHandle::kStateShift, std::memory_order_acquire)) { // Took ownership - uint32_t hash = h.hash; + UniqueId64x2 hashed_key = h.hashed_key; h.FreeData(); usage_.fetch_sub(h.total_charge, std::memory_order_relaxed); #ifndef NDEBUG @@ -801,37 +808,29 @@ void ClockHandleTable::EraseUnRefEntries() { h.meta.store(0, std::memory_order_release); #endif occupancy_.fetch_sub(1U, std::memory_order_release); - Rollback(hash, &h); + Rollback(hashed_key, &h); } } } -namespace { -inline uint32_t Remix1(uint32_t hash) { - return Lower32of64((uint64_t{hash} * 0xbc9f1d35) >> 29); -} - -inline uint32_t Remix2(uint32_t hash) { - return Lower32of64((uint64_t{hash} * 0x7a2bb9d5) >> 29); -} -} // namespace - ClockHandle* ClockHandleTable::FindSlot( - uint32_t hash, std::function match_fn, + const UniqueId64x2& hashed_key, std::function match_fn, std::function abort_fn, - std::function update_fn, uint32_t& probe) { + std::function update_fn, size_t& probe) { + // NOTE: upper 32 bits of hashed_key[0] is used for sharding + // // We use double-hashing probing. Every probe in the sequence is a // pseudorandom integer, computed as a linear function of two random hashes, // which we call base and increment. Specifically, the i-th probe is base + i // * increment modulo the table size. - uint32_t base = ModTableSize(Remix1(hash)); + size_t base = static_cast(hashed_key[1]); // We use an odd increment, which is relatively prime with the power-of-two // table size. This implies that we cycle back to the first probe only // after probing every slot exactly once. // TODO: we could also reconsider linear probing, though locality benefits // are limited because each slot is a full cache line - uint32_t increment = Remix2(hash) | 1U; - uint32_t current = ModTableSize(base + probe * increment); + size_t increment = static_cast(hashed_key[0]) | 1U; + size_t current = ModTableSize(base + probe * increment); while (probe <= length_bits_mask_) { ClockHandle* h = &array_[current]; if (match_fn(h)) { @@ -849,22 +848,23 @@ ClockHandle* ClockHandleTable::FindSlot( return nullptr; } -void ClockHandleTable::Rollback(uint32_t hash, const ClockHandle* h) { - uint32_t current = ModTableSize(Remix1(hash)); - uint32_t increment = Remix2(hash) | 1U; - for (uint32_t i = 0; &array_[current] != h; i++) { +void ClockHandleTable::Rollback(const UniqueId64x2& hashed_key, + const ClockHandle* h) { + size_t current = ModTableSize(hashed_key[1]); + size_t increment = static_cast(hashed_key[0]) | 1U; + for (size_t i = 0; &array_[current] != h; i++) { array_[current].displacements.fetch_sub(1, std::memory_order_relaxed); current = ModTableSize(current + increment); } } void ClockHandleTable::Evict(size_t requested_charge, size_t* freed_charge, - uint32_t* freed_count) { + size_t* freed_count) { // precondition assert(requested_charge > 0); // TODO: make a tuning parameter? - constexpr uint32_t step_size = 4; + constexpr size_t step_size = 4; // First (concurrent) increment clock pointer uint64_t old_clock_pointer = @@ -879,7 +879,7 @@ void ClockHandleTable::Evict(size_t requested_charge, size_t* freed_charge, old_clock_pointer + (ClockHandle::kMaxCountdown << length_bits_); for (;;) { - for (uint32_t i = 0; i < step_size; i++) { + for (size_t i = 0; i < step_size; i++) { ClockHandle& h = array_[ModTableSize(Lower32of64(old_clock_pointer + i))]; uint64_t meta = h.meta.load(std::memory_order_relaxed); @@ -920,7 +920,7 @@ void ClockHandleTable::Evict(size_t requested_charge, size_t* freed_charge, << ClockHandle::kStateShift, std::memory_order_acquire)) { // Took ownership - uint32_t hash = h.hash; + const UniqueId64x2& hashed_key = h.hashed_key; // TODO? Delay freeing? h.FreeData(); *freed_charge += h.total_charge; @@ -934,7 +934,7 @@ void ClockHandleTable::Evict(size_t requested_charge, size_t* freed_charge, h.meta.store(0, std::memory_order_release); #endif *freed_count += 1; - Rollback(hash, &h); + Rollback(hashed_key, &h); } } @@ -955,7 +955,7 @@ void ClockHandleTable::Evict(size_t requested_charge, size_t* freed_charge, ClockCacheShard::ClockCacheShard( size_t capacity, size_t estimated_value_size, bool strict_capacity_limit, CacheMetadataChargePolicy metadata_charge_policy) - : CacheShard(metadata_charge_policy), + : CacheShardBase(metadata_charge_policy), table_( CalcHashBits(capacity, estimated_value_size, metadata_charge_policy), /*initial_charge_metadata*/ metadata_charge_policy == @@ -971,31 +971,33 @@ void ClockCacheShard::EraseUnRefEntries() { table_.EraseUnRefEntries(); } void ClockCacheShard::ApplyToSomeEntries( const std::function& callback, - uint32_t average_entries_per_lock, uint32_t* state) { + size_t average_entries_per_lock, size_t* state) { // The state is essentially going to be the starting hash, which works // nicely even if we resize between calls because we use upper-most // hash bits for table indexes. - uint32_t length_bits = table_.GetLengthBits(); - uint32_t length = table_.GetTableSize(); + size_t length_bits = table_.GetLengthBits(); + size_t length = table_.GetTableSize(); assert(average_entries_per_lock > 0); // Assuming we are called with same average_entries_per_lock repeatedly, // this simplifies some logic (index_end will not overflow). assert(average_entries_per_lock < length || *state == 0); - uint32_t index_begin = *state >> (32 - length_bits); - uint32_t index_end = index_begin + average_entries_per_lock; + size_t index_begin = *state >> (sizeof(size_t) * 8u - length_bits); + size_t index_end = index_begin + average_entries_per_lock; if (index_end >= length) { // Going to end. index_end = length; - *state = UINT32_MAX; + *state = SIZE_MAX; } else { - *state = index_end << (32 - length_bits); + *state = index_end << (sizeof(size_t) * 8u - length_bits); } table_.ConstApplyToEntriesRange( [callback](const ClockHandle& h) { - callback(h.KeySlice(), h.value, h.total_charge, h.deleter); + UniqueId64x2 unhashed; + callback(ReverseHash(h.hashed_key, &unhashed), h.value, h.total_charge, + h.deleter); }, index_begin, index_end, false); } @@ -1011,7 +1013,7 @@ int ClockCacheShard::CalcHashBits( uint64_t num_slots = static_cast(capacity / average_slot_charge + 0.999999); - int hash_bits = std::min(FloorLog2((num_slots << 1) - 1), 32); + int hash_bits = FloorLog2((num_slots << 1) - 1); if (metadata_charge_policy == kFullChargeCacheMetadata) { // For very small estimated value sizes, it's possible to overshoot while (hash_bits > 0 && @@ -1033,17 +1035,16 @@ void ClockCacheShard::SetStrictCapacityLimit(bool strict_capacity_limit) { // next Insert will take care of any necessary evictions } -Status ClockCacheShard::Insert(const Slice& key, uint32_t hash, void* value, - size_t charge, Cache::DeleterFn deleter, - Cache::Handle** handle, +Status ClockCacheShard::Insert(const Slice& key, const UniqueId64x2& hashed_key, + void* value, size_t charge, + Cache::DeleterFn deleter, ClockHandle** handle, Cache::Priority priority) { if (UNLIKELY(key.size() != kCacheKeySize)) { return Status::NotSupported("ClockCache only supports key size " + std::to_string(kCacheKeySize) + "B"); } - ClockHandleMoreData proto; - proto.key = *reinterpret_cast(key.data()); - proto.hash = hash; + ClockHandleBasicData proto; + proto.hashed_key = hashed_key; proto.value = value; proto.deleter = deleter; proto.total_charge = charge; @@ -1054,49 +1055,47 @@ Status ClockCacheShard::Insert(const Slice& key, uint32_t hash, void* value, return s; } -Cache::Handle* ClockCacheShard::Lookup(const Slice& key, uint32_t hash) { +ClockHandle* ClockCacheShard::Lookup(const Slice& key, + const UniqueId64x2& hashed_key) { if (UNLIKELY(key.size() != kCacheKeySize)) { return nullptr; } - auto key_bytes = reinterpret_cast(key.data()); - return reinterpret_cast(table_.Lookup(*key_bytes, hash)); + return table_.Lookup(hashed_key); } -bool ClockCacheShard::Ref(Cache::Handle* h) { +bool ClockCacheShard::Ref(ClockHandle* h) { if (h == nullptr) { return false; } - table_.Ref(*reinterpret_cast(h)); + table_.Ref(*h); return true; } -bool ClockCacheShard::Release(Cache::Handle* handle, bool useful, +bool ClockCacheShard::Release(ClockHandle* handle, bool useful, bool erase_if_last_ref) { if (handle == nullptr) { return false; } - return table_.Release(reinterpret_cast(handle), useful, - erase_if_last_ref); + return table_.Release(handle, useful, erase_if_last_ref); } -void ClockCacheShard::TEST_RefN(Cache::Handle* h, size_t n) { - table_.TEST_RefN(*reinterpret_cast(h), n); +void ClockCacheShard::TEST_RefN(ClockHandle* h, size_t n) { + table_.TEST_RefN(*h, n); } -void ClockCacheShard::TEST_ReleaseN(Cache::Handle* h, size_t n) { - table_.TEST_ReleaseN(reinterpret_cast(h), n); +void ClockCacheShard::TEST_ReleaseN(ClockHandle* h, size_t n) { + table_.TEST_ReleaseN(h, n); } -bool ClockCacheShard::Release(Cache::Handle* handle, bool erase_if_last_ref) { +bool ClockCacheShard::Release(ClockHandle* handle, bool erase_if_last_ref) { return Release(handle, /*useful=*/true, erase_if_last_ref); } -void ClockCacheShard::Erase(const Slice& key, uint32_t hash) { +void ClockCacheShard::Erase(const Slice& key, const UniqueId64x2& hashed_key) { if (UNLIKELY(key.size() != kCacheKeySize)) { return; } - auto key_bytes = reinterpret_cast(key.data()); - table_.Erase(*key_bytes, hash); + table_.Erase(hashed_key); } size_t ClockCacheShard::GetUsage() const { return table_.GetUsage(); } @@ -1140,39 +1139,19 @@ size_t ClockCacheShard::GetTableAddressCount() const { HyperClockCache::HyperClockCache( size_t capacity, size_t estimated_value_size, int num_shard_bits, bool strict_capacity_limit, - CacheMetadataChargePolicy metadata_charge_policy) - : ShardedCache(capacity, num_shard_bits, strict_capacity_limit), - num_shards_(1 << num_shard_bits) { + CacheMetadataChargePolicy metadata_charge_policy, + std::shared_ptr memory_allocator) + : ShardedCache(capacity, num_shard_bits, strict_capacity_limit, + std::move(memory_allocator)) { assert(estimated_value_size > 0 || metadata_charge_policy != kDontChargeCacheMetadata); // TODO: should not need to go through two levels of pointer indirection to // get to table entries - shards_ = reinterpret_cast( - port::cacheline_aligned_alloc(sizeof(ClockCacheShard) * num_shards_)); - size_t per_shard = (capacity + (num_shards_ - 1)) / num_shards_; - for (int i = 0; i < num_shards_; i++) { - new (&shards_[i]) - ClockCacheShard(per_shard, estimated_value_size, strict_capacity_limit, - metadata_charge_policy); - } -} - -HyperClockCache::~HyperClockCache() { - if (shards_ != nullptr) { - assert(num_shards_ > 0); - for (int i = 0; i < num_shards_; i++) { - shards_[i].~ClockCacheShard(); - } - port::cacheline_aligned_free(shards_); - } -} - -CacheShard* HyperClockCache::GetShard(uint32_t shard) { - return reinterpret_cast(&shards_[shard]); -} - -const CacheShard* HyperClockCache::GetShard(uint32_t shard) const { - return reinterpret_cast(&shards_[shard]); + size_t per_shard = GetPerShardCapacity(); + InitShards([=](ClockCacheShard* cs) { + new (cs) ClockCacheShard(per_shard, estimated_value_size, + strict_capacity_limit, metadata_charge_policy); + }); } void* HyperClockCache::Value(Handle* handle) { @@ -1188,18 +1167,6 @@ Cache::DeleterFn HyperClockCache::GetDeleter(Handle* handle) const { return h->deleter; } -uint32_t HyperClockCache::GetHash(Handle* handle) const { - return reinterpret_cast(handle)->hash; -} - -void HyperClockCache::DisownData() { - // Leak data only if that won't generate an ASAN/valgrind warning. - if (!kMustFreeHeapAllocations) { - shards_ = nullptr; - num_shards_ = 0; - } -} - } // namespace hyper_clock_cache // DEPRECATED (see public API) @@ -1225,7 +1192,7 @@ std::shared_ptr HyperClockCacheOptions::MakeSharedCache() const { } return std::make_shared( capacity, estimated_entry_charge, my_num_shard_bits, - strict_capacity_limit, metadata_charge_policy); + strict_capacity_limit, metadata_charge_policy, memory_allocator); } } // namespace ROCKSDB_NAMESPACE diff --git a/cache/clock_cache.h b/cache/clock_cache.h index a68514e36..53a9de5f0 100644 --- a/cache/clock_cache.h +++ b/cache/clock_cache.h @@ -303,30 +303,24 @@ constexpr double kLoadFactor = 0.7; // strict upper bound on the load factor. constexpr double kStrictLoadFactor = 0.84; -using CacheKeyBytes = std::array; - struct ClockHandleBasicData { void* value = nullptr; Cache::DeleterFn deleter = nullptr; - CacheKeyBytes key = {}; + // A lossless, reversible hash of the fixed-size (16 byte) cache key. This + // eliminates the need to store a hash separately. + UniqueId64x2 hashed_key = kNullUniqueId64x2; size_t total_charge = 0; - Slice KeySlice() const { return Slice(key.data(), kCacheKeySize); } + // Calls deleter (if non-null) on cache key and value + void FreeData() const; - void FreeData() const { - if (deleter) { - (*deleter)(KeySlice(), value); - } - } -}; - -struct ClockHandleMoreData : public ClockHandleBasicData { - uint32_t hash = 0; + // Required by concept HandleImpl + const UniqueId64x2& GetHash() const { return hashed_key; } }; // Target size to be exactly a common cache line size (see static_assert in // clock_cache.cc) -struct ALIGN_AS(64U) ClockHandle : public ClockHandleMoreData { +struct ALIGN_AS(64U) ClockHandle : public ClockHandleBasicData { // Constants for handling the atomic `meta` word, which tracks most of the // state of the handle. The meta word looks like this: // low bits high bits @@ -391,31 +385,31 @@ class ClockHandleTable { explicit ClockHandleTable(int hash_bits, bool initial_charge_metadata); ~ClockHandleTable(); - Status Insert(const ClockHandleMoreData& proto, ClockHandle** handle, + Status Insert(const ClockHandleBasicData& proto, ClockHandle** handle, Cache::Priority priority, size_t capacity, bool strict_capacity_limit); - ClockHandle* Lookup(const CacheKeyBytes& key, uint32_t hash); + ClockHandle* Lookup(const UniqueId64x2& hashed_key); bool Release(ClockHandle* handle, bool useful, bool erase_if_last_ref); void Ref(ClockHandle& handle); - void Erase(const CacheKeyBytes& key, uint32_t hash); + void Erase(const UniqueId64x2& hashed_key); void ConstApplyToEntriesRange(std::function func, - uint32_t index_begin, uint32_t index_end, + size_t index_begin, size_t index_end, bool apply_if_will_be_deleted) const; void EraseUnRefEntries(); - uint32_t GetTableSize() const { return uint32_t{1} << length_bits_; } + size_t GetTableSize() const { return size_t{1} << length_bits_; } int GetLengthBits() const { return length_bits_; } - uint32_t GetOccupancyLimit() const { return occupancy_limit_; } + size_t GetOccupancyLimit() const { return occupancy_limit_; } - uint32_t GetOccupancy() const { + size_t GetOccupancy() const { return occupancy_.load(std::memory_order_relaxed); } @@ -431,13 +425,15 @@ class ClockHandleTable { private: // functions // Returns x mod 2^{length_bits_}. - uint32_t ModTableSize(uint32_t x) { return x & length_bits_mask_; } + inline size_t ModTableSize(uint64_t x) { + return static_cast(x) & length_bits_mask_; + } // Runs the clock eviction algorithm trying to reclaim at least // requested_charge. Returns how much is evicted, which could be less // if it appears impossible to evict the requested amount without blocking. void Evict(size_t requested_charge, size_t* freed_charge, - uint32_t* freed_count); + size_t* freed_count); // Returns the first slot in the probe sequence, starting from the given // probe number, with a handle e such that match(e) is true. At every @@ -450,15 +446,15 @@ class ClockHandleTable { // value of probe is one more than the last non-aborting probe during the // call. This is so that that the variable can be used to keep track of // progress across consecutive calls to FindSlot. - inline ClockHandle* FindSlot(uint32_t hash, + inline ClockHandle* FindSlot(const UniqueId64x2& hashed_key, std::function match, std::function stop, std::function update, - uint32_t& probe); + size_t& probe); // Re-decrement all displacements in probe path starting from beginning // until (not including) the given handle - void Rollback(uint32_t hash, const ClockHandle* h); + void Rollback(const UniqueId64x2& hashed_key, const ClockHandle* h); private: // data // Number of hash bits used for table index. @@ -466,10 +462,10 @@ class ClockHandleTable { const int length_bits_; // For faster computation of ModTableSize. - const uint32_t length_bits_mask_; + const size_t length_bits_mask_; // Maximum number of elements the user can store in the table. - const uint32_t occupancy_limit_; + const size_t occupancy_limit_; // Array of slots comprising the hash table. const std::unique_ptr array_; @@ -484,7 +480,7 @@ class ClockHandleTable { ALIGN_AS(CACHE_LINE_SIZE) // Number of elements in the table. - std::atomic occupancy_{}; + std::atomic occupancy_{}; // Memory usage by entries tracked by the cache (including detached) std::atomic usage_{}; @@ -494,78 +490,107 @@ class ClockHandleTable { }; // class ClockHandleTable // A single shard of sharded cache. -class ALIGN_AS(CACHE_LINE_SIZE) ClockCacheShard final : public CacheShard { +class ALIGN_AS(CACHE_LINE_SIZE) ClockCacheShard final : public CacheShardBase { public: ClockCacheShard(size_t capacity, size_t estimated_value_size, bool strict_capacity_limit, CacheMetadataChargePolicy metadata_charge_policy); - ~ClockCacheShard() override = default; - // TODO: document limitations - void SetCapacity(size_t capacity) override; + // For CacheShard concept + using HandleImpl = ClockHandle; + // Hash is lossless hash of 128-bit key + using HashVal = UniqueId64x2; + using HashCref = const HashVal&; + static inline uint32_t HashPieceForSharding(HashCref hash) { + return Upper32of64(hash[0]); + } + static inline HashVal ComputeHash(const Slice& key) { + assert(key.size() == kCacheKeySize); + HashVal in; + HashVal out; + // NOTE: endian dependence + // TODO: use GetUnaligned? + std::memcpy(&in, key.data(), kCacheKeySize); + BijectiveHash2x64(in[1], in[0], &out[1], &out[0]); + return out; + } + + // For reconstructing key from hashed_key. Requires the caller to provide + // backing storage for the Slice in `unhashed` + static inline Slice ReverseHash(const UniqueId64x2& hashed, + UniqueId64x2* unhashed) { + BijectiveUnhash2x64(hashed[1], hashed[0], &(*unhashed)[1], &(*unhashed)[0]); + // NOTE: endian dependence + return Slice(reinterpret_cast(unhashed), kCacheKeySize); + } + + // Although capacity is dynamically changeable, the number of table slots is + // not, so growing capacity substantially could lead to hitting occupancy + // limit. + void SetCapacity(size_t capacity); - void SetStrictCapacityLimit(bool strict_capacity_limit) override; + void SetStrictCapacityLimit(bool strict_capacity_limit); - Status Insert(const Slice& key, uint32_t hash, void* value, size_t charge, - Cache::DeleterFn deleter, Cache::Handle** handle, - Cache::Priority priority) override; + Status Insert(const Slice& key, const UniqueId64x2& hashed_key, void* value, + size_t charge, Cache::DeleterFn deleter, ClockHandle** handle, + Cache::Priority priority); - Cache::Handle* Lookup(const Slice& key, uint32_t hash) override; + ClockHandle* Lookup(const Slice& key, const UniqueId64x2& hashed_key); - bool Release(Cache::Handle* handle, bool useful, - bool erase_if_last_ref) override; + bool Release(ClockHandle* handle, bool useful, bool erase_if_last_ref); - bool Release(Cache::Handle* handle, bool erase_if_last_ref = false) override; + bool Release(ClockHandle* handle, bool erase_if_last_ref = false); - bool Ref(Cache::Handle* handle) override; + bool Ref(ClockHandle* handle); - void Erase(const Slice& key, uint32_t hash) override; + void Erase(const Slice& key, const UniqueId64x2& hashed_key); - size_t GetUsage() const override; + size_t GetUsage() const; - size_t GetPinnedUsage() const override; + size_t GetPinnedUsage() const; - size_t GetOccupancyCount() const override; + size_t GetOccupancyCount() const; - size_t GetTableAddressCount() const override; + size_t GetTableAddressCount() const; void ApplyToSomeEntries( const std::function& callback, - uint32_t average_entries_per_lock, uint32_t* state) override; + size_t average_entries_per_lock, size_t* state); - void EraseUnRefEntries() override; + void EraseUnRefEntries(); - std::string GetPrintableOptions() const override { return std::string{}; } + std::string GetPrintableOptions() const { return std::string{}; } // SecondaryCache not yet supported - Status Insert(const Slice& key, uint32_t hash, void* value, + Status Insert(const Slice& key, const UniqueId64x2& hashed_key, void* value, const Cache::CacheItemHelper* helper, size_t charge, - Cache::Handle** handle, Cache::Priority priority) override { - return Insert(key, hash, value, charge, helper->del_cb, handle, priority); + ClockHandle** handle, Cache::Priority priority) { + return Insert(key, hashed_key, value, charge, helper->del_cb, handle, + priority); } - Cache::Handle* Lookup(const Slice& key, uint32_t hash, - const Cache::CacheItemHelper* /*helper*/, - const Cache::CreateCallback& /*create_cb*/, - Cache::Priority /*priority*/, bool /*wait*/, - Statistics* /*stats*/) override { - return Lookup(key, hash); + ClockHandle* Lookup(const Slice& key, const UniqueId64x2& hashed_key, + const Cache::CacheItemHelper* /*helper*/, + const Cache::CreateCallback& /*create_cb*/, + Cache::Priority /*priority*/, bool /*wait*/, + Statistics* /*stats*/) { + return Lookup(key, hashed_key); } - bool IsReady(Cache::Handle* /*handle*/) override { return true; } + bool IsReady(ClockHandle* /*handle*/) { return true; } - void Wait(Cache::Handle* /*handle*/) override {} + void Wait(ClockHandle* /*handle*/) {} // Acquire/release N references - void TEST_RefN(Cache::Handle* handle, size_t n); - void TEST_ReleaseN(Cache::Handle* handle, size_t n); + void TEST_RefN(ClockHandle* handle, size_t n); + void TEST_ReleaseN(ClockHandle* handle, size_t n); private: // functions friend class ClockCache; friend class ClockCacheTest; - ClockHandle* DetachedInsert(const ClockHandleMoreData& h); + ClockHandle* DetachedInsert(const ClockHandleBasicData& h); // Returns the number of bits used to hash an element in the hash // table. @@ -586,35 +611,20 @@ class HyperClockCache #ifdef NDEBUG final #endif - : public ShardedCache { + : public ShardedCache { public: HyperClockCache(size_t capacity, size_t estimated_value_size, int num_shard_bits, bool strict_capacity_limit, - CacheMetadataChargePolicy metadata_charge_policy = - kDontChargeCacheMetadata); - - ~HyperClockCache() override; + CacheMetadataChargePolicy metadata_charge_policy, + std::shared_ptr memory_allocator); const char* Name() const override { return "HyperClockCache"; } - CacheShard* GetShard(uint32_t shard) override; - - const CacheShard* GetShard(uint32_t shard) const override; - void* Value(Handle* handle) override; size_t GetCharge(Handle* handle) const override; - uint32_t GetHash(Handle* handle) const override; - DeleterFn GetDeleter(Handle* handle) const override; - - void DisownData() override; - - private: - ClockCacheShard* shards_ = nullptr; - - int num_shards_; }; // class HyperClockCache } // namespace hyper_clock_cache diff --git a/cache/fast_lru_cache.cc b/cache/fast_lru_cache.cc index f5f93800d..3a540f139 100644 --- a/cache/fast_lru_cache.cc +++ b/cache/fast_lru_cache.cc @@ -173,7 +173,7 @@ inline int LRUHandleTable::FindSlot(const Slice& key, LRUCacheShard::LRUCacheShard(size_t capacity, size_t estimated_value_size, bool strict_capacity_limit, CacheMetadataChargePolicy metadata_charge_policy) - : CacheShard(metadata_charge_policy), + : CacheShardBase(metadata_charge_policy), capacity_(capacity), strict_capacity_limit_(strict_capacity_limit), table_( @@ -211,27 +211,27 @@ void LRUCacheShard::EraseUnRefEntries() { void LRUCacheShard::ApplyToSomeEntries( const std::function& callback, - uint32_t average_entries_per_lock, uint32_t* state) { + size_t average_entries_per_lock, size_t* state) { // The state is essentially going to be the starting hash, which works // nicely even if we resize between calls because we use upper-most // hash bits for table indexes. DMutexLock l(mutex_); - uint32_t length_bits = table_.GetLengthBits(); - uint32_t length = table_.GetTableSize(); + size_t length_bits = table_.GetLengthBits(); + size_t length = table_.GetTableSize(); assert(average_entries_per_lock > 0); // Assuming we are called with same average_entries_per_lock repeatedly, // this simplifies some logic (index_end will not overflow). assert(average_entries_per_lock < length || *state == 0); - uint32_t index_begin = *state >> (32 - length_bits); - uint32_t index_end = index_begin + average_entries_per_lock; + size_t index_begin = *state >> (sizeof(size_t) * 8u - length_bits); + size_t index_end = index_begin + average_entries_per_lock; if (index_end >= length) { // Going to end index_end = length; - *state = UINT32_MAX; + *state = SIZE_MAX; } else { - *state = index_end << (32 - length_bits); + *state = index_end << (sizeof(size_t) * 8u - length_bits); } table_.ApplyToEntriesRange( @@ -322,8 +322,7 @@ void LRUCacheShard::SetStrictCapacityLimit(bool strict_capacity_limit) { Status LRUCacheShard::Insert(const Slice& key, uint32_t hash, void* value, size_t charge, Cache::DeleterFn deleter, - Cache::Handle** handle, - Cache::Priority /*priority*/) { + LRUHandle** handle, Cache::Priority /*priority*/) { if (key.size() != kCacheKeySize) { return Status::NotSupported("FastLRUCache only supports key size " + std::to_string(kCacheKeySize) + "B"); @@ -409,7 +408,7 @@ Status LRUCacheShard::Insert(const Slice& key, uint32_t hash, void* value, if (!h->HasRefs()) { h->Ref(); } - *handle = reinterpret_cast(h); + *handle = h; } } } @@ -422,7 +421,7 @@ Status LRUCacheShard::Insert(const Slice& key, uint32_t hash, void* value, return s; } -Cache::Handle* LRUCacheShard::Lookup(const Slice& key, uint32_t hash) { +LRUHandle* LRUCacheShard::Lookup(const Slice& key, uint32_t hash) { LRUHandle* h = nullptr; { DMutexLock l(mutex_); @@ -437,23 +436,21 @@ Cache::Handle* LRUCacheShard::Lookup(const Slice& key, uint32_t hash) { h->Ref(); } } - return reinterpret_cast(h); + return h; } -bool LRUCacheShard::Ref(Cache::Handle* h) { - LRUHandle* e = reinterpret_cast(h); +bool LRUCacheShard::Ref(LRUHandle* h) { DMutexLock l(mutex_); // To create another reference - entry must be already externally referenced. - assert(e->HasRefs()); - e->Ref(); + assert(h->HasRefs()); + h->Ref(); return true; } -bool LRUCacheShard::Release(Cache::Handle* handle, bool erase_if_last_ref) { - if (handle == nullptr) { +bool LRUCacheShard::Release(LRUHandle* h, bool erase_if_last_ref) { + if (h == nullptr) { return false; } - LRUHandle* h = reinterpret_cast(handle); LRUHandle copy; bool last_reference = false; { @@ -535,41 +532,18 @@ size_t LRUCacheShard::GetTableAddressCount() const { return table_.GetTableSize(); } -std::string LRUCacheShard::GetPrintableOptions() const { return std::string{}; } - LRUCache::LRUCache(size_t capacity, size_t estimated_value_size, int num_shard_bits, bool strict_capacity_limit, CacheMetadataChargePolicy metadata_charge_policy) - : ShardedCache(capacity, num_shard_bits, strict_capacity_limit) { + : ShardedCache(capacity, num_shard_bits, strict_capacity_limit, + nullptr /*allocator*/) { assert(estimated_value_size > 0 || metadata_charge_policy != kDontChargeCacheMetadata); - num_shards_ = 1 << num_shard_bits; - shards_ = reinterpret_cast( - port::cacheline_aligned_alloc(sizeof(LRUCacheShard) * num_shards_)); - size_t per_shard = (capacity + (num_shards_ - 1)) / num_shards_; - for (int i = 0; i < num_shards_; i++) { - new (&shards_[i]) - LRUCacheShard(per_shard, estimated_value_size, strict_capacity_limit, - metadata_charge_policy); - } -} - -LRUCache::~LRUCache() { - if (shards_ != nullptr) { - assert(num_shards_ > 0); - for (int i = 0; i < num_shards_; i++) { - shards_[i].~LRUCacheShard(); - } - port::cacheline_aligned_free(shards_); - } -} - -CacheShard* LRUCache::GetShard(uint32_t shard) { - return reinterpret_cast(&shards_[shard]); -} - -const CacheShard* LRUCache::GetShard(uint32_t shard) const { - return reinterpret_cast(&shards_[shard]); + size_t per_shard = GetPerShardCapacity(); + InitShards([=](LRUCacheShard* cs) { + new (cs) LRUCacheShard(per_shard, estimated_value_size, + strict_capacity_limit, metadata_charge_policy); + }); } void* LRUCache::Value(Handle* handle) { @@ -577,12 +551,8 @@ void* LRUCache::Value(Handle* handle) { } size_t LRUCache::GetCharge(Handle* handle) const { - CacheMetadataChargePolicy metadata_charge_policy = kDontChargeCacheMetadata; - if (num_shards_ > 0) { - metadata_charge_policy = shards_[0].metadata_charge_policy_; - } return reinterpret_cast(handle)->GetCharge( - metadata_charge_policy); + GetShard(0).metadata_charge_policy_); } Cache::DeleterFn LRUCache::GetDeleter(Handle* handle) const { @@ -590,18 +560,6 @@ Cache::DeleterFn LRUCache::GetDeleter(Handle* handle) const { return h->deleter; } -uint32_t LRUCache::GetHash(Handle* handle) const { - return reinterpret_cast(handle)->hash; -} - -void LRUCache::DisownData() { - // Leak data only if that won't generate an ASAN/valgrind warning. - if (!kMustFreeHeapAllocations) { - shards_ = nullptr; - num_shards_ = 0; - } -} - } // namespace fast_lru_cache std::shared_ptr NewFastLRUCache( diff --git a/cache/fast_lru_cache.h b/cache/fast_lru_cache.h index 77aff8bab..3cd55ca86 100644 --- a/cache/fast_lru_cache.h +++ b/cache/fast_lru_cache.h @@ -141,6 +141,9 @@ struct LRUHandle { Slice key() const { return Slice(key_data.data(), kCacheKeySize); } + // For HandleImpl concept + uint32_t GetHash() const { return hash; } + // Increase the reference count by 1. void Ref() { refs++; } @@ -260,8 +263,8 @@ class LRUHandleTable { void Assign(int slot, LRUHandle* h); template - void ApplyToEntriesRange(T func, uint32_t index_begin, uint32_t index_end) { - for (uint32_t i = index_begin; i < index_end; i++) { + void ApplyToEntriesRange(T func, size_t index_begin, size_t index_end) { + for (size_t i = index_begin; i < index_end; i++) { LRUHandle* h = &array_[i]; if (h->IsVisible()) { func(h); @@ -316,20 +319,30 @@ class LRUHandleTable { }; // A single shard of sharded cache. -class ALIGN_AS(CACHE_LINE_SIZE) LRUCacheShard final : public CacheShard { +class ALIGN_AS(CACHE_LINE_SIZE) LRUCacheShard final : public CacheShardBase { public: LRUCacheShard(size_t capacity, size_t estimated_value_size, bool strict_capacity_limit, CacheMetadataChargePolicy metadata_charge_policy); - ~LRUCacheShard() override = default; + + // For CacheShard concept + using HandleImpl = LRUHandle; + + // Keep 32-bit hashing for now (FIXME: upgrade to 64-bit) + using HashVal = uint32_t; + using HashCref = uint32_t; + static inline HashVal ComputeHash(const Slice& key) { + return Lower32of64(GetSliceNPHash64(key)); + } + static inline uint32_t HashPieceForSharding(HashCref hash) { return hash; } // Separate from constructor so caller can easily make an array of LRUCache // if current usage is more than new capacity, the function will attempt to // free the needed space. - void SetCapacity(size_t capacity) override; + void SetCapacity(size_t capacity); // Set the flag to reject insertion if cache if full. - void SetStrictCapacityLimit(bool strict_capacity_limit) override; + void SetStrictCapacityLimit(bool strict_capacity_limit); // Like Cache methods, but with an extra "hash" parameter. // Insert an item into the hash table and, if handle is null, insert into @@ -337,48 +350,45 @@ class ALIGN_AS(CACHE_LINE_SIZE) LRUCacheShard final : public CacheShard { // and free_handle_on_fail is true, the item is deleted and handle is set to // nullptr. Status Insert(const Slice& key, uint32_t hash, void* value, size_t charge, - Cache::DeleterFn deleter, Cache::Handle** handle, - Cache::Priority priority) override; + Cache::DeleterFn deleter, LRUHandle** handle, + Cache::Priority priority); Status Insert(const Slice& key, uint32_t hash, void* value, const Cache::CacheItemHelper* helper, size_t charge, - Cache::Handle** handle, Cache::Priority priority) override { + LRUHandle** handle, Cache::Priority priority) { return Insert(key, hash, value, charge, helper->del_cb, handle, priority); } - Cache::Handle* Lookup(const Slice& key, uint32_t hash, - const Cache::CacheItemHelper* /*helper*/, - const Cache::CreateCallback& /*create_cb*/, - Cache::Priority /*priority*/, bool /*wait*/, - Statistics* /*stats*/) override { + LRUHandle* Lookup(const Slice& key, uint32_t hash, + const Cache::CacheItemHelper* /*helper*/, + const Cache::CreateCallback& /*create_cb*/, + Cache::Priority /*priority*/, bool /*wait*/, + Statistics* /*stats*/) { return Lookup(key, hash); } - Cache::Handle* Lookup(const Slice& key, uint32_t hash) override; + LRUHandle* Lookup(const Slice& key, uint32_t hash); - bool Release(Cache::Handle* handle, bool /*useful*/, - bool erase_if_last_ref) override { + bool Release(LRUHandle* handle, bool /*useful*/, bool erase_if_last_ref) { return Release(handle, erase_if_last_ref); } - bool IsReady(Cache::Handle* /*handle*/) override { return true; } - void Wait(Cache::Handle* /*handle*/) override {} + bool IsReady(LRUHandle* /*handle*/) { return true; } + void Wait(LRUHandle* /*handle*/) {} - bool Ref(Cache::Handle* handle) override; - bool Release(Cache::Handle* handle, bool erase_if_last_ref = false) override; - void Erase(const Slice& key, uint32_t hash) override; + bool Ref(LRUHandle* handle); + bool Release(LRUHandle* handle, bool erase_if_last_ref = false); + void Erase(const Slice& key, uint32_t hash); - size_t GetUsage() const override; - size_t GetPinnedUsage() const override; - size_t GetOccupancyCount() const override; - size_t GetTableAddressCount() const override; + size_t GetUsage() const; + size_t GetPinnedUsage() const; + size_t GetOccupancyCount() const; + size_t GetTableAddressCount() const; void ApplyToSomeEntries( const std::function& callback, - uint32_t average_entries_per_lock, uint32_t* state) override; - - void EraseUnRefEntries() override; + size_t average_entries_per_lock, size_t* state); - std::string GetPrintableOptions() const override; + void EraseUnRefEntries(); private: friend class LRUCache; @@ -446,25 +456,16 @@ class LRUCache #ifdef NDEBUG final #endif - : public ShardedCache { + : public ShardedCache { public: LRUCache(size_t capacity, size_t estimated_value_size, int num_shard_bits, bool strict_capacity_limit, CacheMetadataChargePolicy metadata_charge_policy = kDontChargeCacheMetadata); - ~LRUCache() override; const char* Name() const override { return "LRUCache"; } - CacheShard* GetShard(uint32_t shard) override; - const CacheShard* GetShard(uint32_t shard) const override; void* Value(Handle* handle) override; size_t GetCharge(Handle* handle) const override; - uint32_t GetHash(Handle* handle) const override; DeleterFn GetDeleter(Handle* handle) const override; - void DisownData() override; - - private: - LRUCacheShard* shards_ = nullptr; - int num_shards_ = 0; }; } // namespace fast_lru_cache diff --git a/cache/lru_cache.cc b/cache/lru_cache.cc index afecedde9..06d223f3a 100644 --- a/cache/lru_cache.cc +++ b/cache/lru_cache.cc @@ -38,7 +38,7 @@ LRUHandleTable::~LRUHandleTable() { h->Free(); } }, - 0, uint32_t{1} << length_bits_); + 0, size_t{1} << length_bits_); } LRUHandle* LRUHandleTable::Lookup(const Slice& key, uint32_t hash) { @@ -113,12 +113,13 @@ void LRUHandleTable::Resize() { length_bits_ = new_length_bits; } -LRUCacheShard::LRUCacheShard( - size_t capacity, bool strict_capacity_limit, double high_pri_pool_ratio, - double low_pri_pool_ratio, bool use_adaptive_mutex, - CacheMetadataChargePolicy metadata_charge_policy, int max_upper_hash_bits, - const std::shared_ptr& secondary_cache) - : CacheShard(metadata_charge_policy), +LRUCacheShard::LRUCacheShard(size_t capacity, bool strict_capacity_limit, + double high_pri_pool_ratio, + double low_pri_pool_ratio, bool use_adaptive_mutex, + CacheMetadataChargePolicy metadata_charge_policy, + int max_upper_hash_bits, + SecondaryCache* secondary_cache) + : CacheShardBase(metadata_charge_policy), capacity_(0), high_pri_pool_usage_(0), low_pri_pool_usage_(0), @@ -165,27 +166,27 @@ void LRUCacheShard::EraseUnRefEntries() { void LRUCacheShard::ApplyToSomeEntries( const std::function& callback, - uint32_t average_entries_per_lock, uint32_t* state) { + size_t average_entries_per_lock, size_t* state) { // The state is essentially going to be the starting hash, which works // nicely even if we resize between calls because we use upper-most // hash bits for table indexes. DMutexLock l(mutex_); - uint32_t length_bits = table_.GetLengthBits(); - uint32_t length = uint32_t{1} << length_bits; + int length_bits = table_.GetLengthBits(); + size_t length = size_t{1} << length_bits; assert(average_entries_per_lock > 0); // Assuming we are called with same average_entries_per_lock repeatedly, // this simplifies some logic (index_end will not overflow). assert(average_entries_per_lock < length || *state == 0); - uint32_t index_begin = *state >> (32 - length_bits); - uint32_t index_end = index_begin + average_entries_per_lock; + size_t index_begin = *state >> (sizeof(size_t) * 8u - length_bits); + size_t index_end = index_begin + average_entries_per_lock; if (index_end >= length) { // Going to end index_end = length; - *state = UINT32_MAX; + *state = SIZE_MAX; } else { - *state = index_end << (32 - length_bits); + *state = index_end << (sizeof(size_t) * 8u - length_bits); } table_.ApplyToEntriesRange( @@ -364,7 +365,7 @@ void LRUCacheShard::SetStrictCapacityLimit(bool strict_capacity_limit) { strict_capacity_limit_ = strict_capacity_limit; } -Status LRUCacheShard::InsertItem(LRUHandle* e, Cache::Handle** handle, +Status LRUCacheShard::InsertItem(LRUHandle* e, LRUHandle** handle, bool free_handle_on_fail) { Status s = Status::OK(); autovector last_reference_list; @@ -414,7 +415,7 @@ Status LRUCacheShard::InsertItem(LRUHandle* e, Cache::Handle** handle, if (!e->HasRefs()) { e->Ref(); } - *handle = reinterpret_cast(e); + *handle = e; } } } @@ -480,7 +481,7 @@ void LRUCacheShard::Promote(LRUHandle* e) { priority); } else { e->SetInCache(true); - Cache::Handle* handle = reinterpret_cast(e); + LRUHandle* handle = e; // This InsertItem() could fail if the cache is over capacity and // strict_capacity_limit_ is true. In such a case, we don't want // InsertItem() to free the handle, since the item is already in memory @@ -505,11 +506,11 @@ void LRUCacheShard::Promote(LRUHandle* e) { } } -Cache::Handle* LRUCacheShard::Lookup( - const Slice& key, uint32_t hash, - const ShardedCache::CacheItemHelper* helper, - const ShardedCache::CreateCallback& create_cb, Cache::Priority priority, - bool wait, Statistics* stats) { +LRUHandle* LRUCacheShard::Lookup(const Slice& key, uint32_t hash, + const Cache::CacheItemHelper* helper, + const Cache::CreateCallback& create_cb, + Cache::Priority priority, bool wait, + Statistics* stats) { LRUHandle* e = nullptr; bool found_dummy_entry{false}; { @@ -607,11 +608,10 @@ Cache::Handle* LRUCacheShard::Lookup( assert(e == nullptr); } } - return reinterpret_cast(e); + return e; } -bool LRUCacheShard::Ref(Cache::Handle* h) { - LRUHandle* e = reinterpret_cast(h); +bool LRUCacheShard::Ref(LRUHandle* e) { DMutexLock l(mutex_); // To create another reference - entry must be already externally referenced. assert(e->HasRefs()); @@ -635,11 +635,11 @@ void LRUCacheShard::SetLowPriorityPoolRatio(double low_pri_pool_ratio) { MaintainPoolSize(); } -bool LRUCacheShard::Release(Cache::Handle* handle, bool erase_if_last_ref) { - if (handle == nullptr) { +bool LRUCacheShard::Release(LRUHandle* e, bool /*useful*/, + bool erase_if_last_ref) { + if (e == nullptr) { return false; } - LRUHandle* e = reinterpret_cast(handle); bool last_reference = false; // Must Wait or WaitAll first on pending handles. Otherwise, would leak // a secondary cache handle. @@ -679,7 +679,7 @@ Status LRUCacheShard::Insert(const Slice& key, uint32_t hash, void* value, size_t charge, void (*deleter)(const Slice& key, void* value), const Cache::CacheItemHelper* helper, - Cache::Handle** handle, Cache::Priority priority) { + LRUHandle** handle, Cache::Priority priority) { // Allocate the memory here outside of the mutex. // If the cache is full, we'll have to release it. // It shouldn't happen very often though. @@ -738,8 +738,7 @@ void LRUCacheShard::Erase(const Slice& key, uint32_t hash) { } } -bool LRUCacheShard::IsReady(Cache::Handle* handle) { - LRUHandle* e = reinterpret_cast(handle); +bool LRUCacheShard::IsReady(LRUHandle* e) { bool ready = true; if (e->IsPending()) { assert(secondary_cache_); @@ -770,7 +769,7 @@ size_t LRUCacheShard::GetTableAddressCount() const { return size_t{1} << table_.GetLengthBits(); } -std::string LRUCacheShard::GetPrintableOptions() const { +void LRUCacheShard::AppendPrintableOptions(std::string& str) const { const int kBufferSize = 200; char buffer[kBufferSize]; { @@ -780,7 +779,7 @@ std::string LRUCacheShard::GetPrintableOptions() const { snprintf(buffer + strlen(buffer), kBufferSize - strlen(buffer), " low_pri_pool_ratio: %.3lf\n", low_pri_pool_ratio_); } - return std::string(buffer); + str.append(buffer); } LRUCache::LRUCache(size_t capacity, int num_shard_bits, @@ -789,38 +788,18 @@ LRUCache::LRUCache(size_t capacity, int num_shard_bits, std::shared_ptr allocator, bool use_adaptive_mutex, CacheMetadataChargePolicy metadata_charge_policy, - const std::shared_ptr& secondary_cache) + std::shared_ptr _secondary_cache) : ShardedCache(capacity, num_shard_bits, strict_capacity_limit, - std::move(allocator)) { - num_shards_ = 1 << num_shard_bits; - shards_ = reinterpret_cast( - port::cacheline_aligned_alloc(sizeof(LRUCacheShard) * num_shards_)); - size_t per_shard = (capacity + (num_shards_ - 1)) / num_shards_; - for (int i = 0; i < num_shards_; i++) { - new (&shards_[i]) LRUCacheShard( + std::move(allocator)), + secondary_cache_(std::move(_secondary_cache)) { + size_t per_shard = GetPerShardCapacity(); + SecondaryCache* secondary_cache = secondary_cache_.get(); + InitShards([=](LRUCacheShard* cs) { + new (cs) LRUCacheShard( per_shard, strict_capacity_limit, high_pri_pool_ratio, low_pri_pool_ratio, use_adaptive_mutex, metadata_charge_policy, /* max_upper_hash_bits */ 32 - num_shard_bits, secondary_cache); - } - secondary_cache_ = secondary_cache; -} - -LRUCache::~LRUCache() { - if (shards_ != nullptr) { - assert(num_shards_ > 0); - for (int i = 0; i < num_shards_; i++) { - shards_[i].~LRUCacheShard(); - } - port::cacheline_aligned_free(shards_); - } -} - -CacheShard* LRUCache::GetShard(uint32_t shard) { - return reinterpret_cast(&shards_[shard]); -} - -const CacheShard* LRUCache::GetShard(uint32_t shard) const { - return reinterpret_cast(&shards_[shard]); + }); } void* LRUCache::Value(Handle* handle) { @@ -831,12 +810,8 @@ void* LRUCache::Value(Handle* handle) { } size_t LRUCache::GetCharge(Handle* handle) const { - CacheMetadataChargePolicy metadata_charge_policy = kDontChargeCacheMetadata; - if (num_shards_ > 0) { - metadata_charge_policy = shards_[0].metadata_charge_policy_; - } return reinterpret_cast(handle)->GetCharge( - metadata_charge_policy); + GetShard(0).metadata_charge_policy_); } Cache::DeleterFn LRUCache::GetDeleter(Handle* handle) const { @@ -848,32 +823,12 @@ Cache::DeleterFn LRUCache::GetDeleter(Handle* handle) const { } } -uint32_t LRUCache::GetHash(Handle* handle) const { - return reinterpret_cast(handle)->hash; -} - -void LRUCache::DisownData() { - // Leak data only if that won't generate an ASAN/valgrind warning. - if (!kMustFreeHeapAllocations) { - shards_ = nullptr; - num_shards_ = 0; - } -} - size_t LRUCache::TEST_GetLRUSize() { - size_t lru_size_of_all_shards = 0; - for (int i = 0; i < num_shards_; i++) { - lru_size_of_all_shards += shards_[i].TEST_GetLRUSize(); - } - return lru_size_of_all_shards; + return SumOverShards([](LRUCacheShard& cs) { return cs.TEST_GetLRUSize(); }); } double LRUCache::GetHighPriPoolRatio() { - double result = 0.0; - if (num_shards_ > 0) { - result = shards_[0].GetHighPriPoolRatio(); - } - return result; + return GetShard(0).GetHighPriPoolRatio(); } void LRUCache::WaitAll(std::vector& handles) { @@ -899,22 +854,17 @@ void LRUCache::WaitAll(std::vector& handles) { if (!lru_handle->IsPending()) { continue; } - uint32_t hash = GetHash(handle); - LRUCacheShard* shard = static_cast(GetShard(Shard(hash))); - shard->Promote(lru_handle); + GetShard(lru_handle->hash).Promote(lru_handle); } } } -std::string LRUCache::GetPrintableOptions() const { - std::string ret; - ret.reserve(20000); - ret.append(ShardedCache::GetPrintableOptions()); +void LRUCache::AppendPrintableOptions(std::string& str) const { + ShardedCache::AppendPrintableOptions(str); // options from shard if (secondary_cache_) { - ret.append(" secondary_cache:\n"); - ret.append(secondary_cache_->GetPrintableOptions()); + str.append(" secondary_cache:\n"); + str.append(secondary_cache_->GetPrintableOptions()); } - return ret; } } // namespace lru_cache diff --git a/cache/lru_cache.h b/cache/lru_cache.h index 062cbcb67..ff5d36467 100644 --- a/cache/lru_cache.h +++ b/cache/lru_cache.h @@ -53,7 +53,7 @@ struct LRUHandle { Info() {} ~Info() {} Cache::DeleterFn deleter; - const ShardedCache::CacheItemHelper* helper; + const Cache::CacheItemHelper* helper; } info_; // An entry is not added to the LRUHandleTable until the secondary cache // lookup is complete, so its safe to have this union. @@ -108,6 +108,9 @@ struct LRUHandle { Slice key() const { return Slice(key_data, key_length); } + // For HandleImpl concept + uint32_t GetHash() const { return hash; } + // Increase the reference count by 1. void Ref() { refs++; } @@ -262,9 +265,6 @@ struct LRUHandle { // 4.4.3's builtin hashtable. class LRUHandleTable { public: - // If the table uses more hash bits than `max_upper_hash_bits`, - // it will eat into the bits used for sharding, which are constant - // for a given LRUHandleTable. explicit LRUHandleTable(int max_upper_hash_bits); ~LRUHandleTable(); @@ -273,8 +273,8 @@ class LRUHandleTable { LRUHandle* Remove(const Slice& key, uint32_t hash); template - void ApplyToEntriesRange(T func, uint32_t index_begin, uint32_t index_end) { - for (uint32_t i = index_begin; i < index_end; i++) { + void ApplyToEntriesRange(T func, size_t index_begin, size_t index_end) { + for (size_t i = index_begin; i < index_end; i++) { LRUHandle* h = list_[i]; while (h != nullptr) { auto n = h->next_hash; @@ -313,23 +313,31 @@ class LRUHandleTable { }; // A single shard of sharded cache. -class ALIGN_AS(CACHE_LINE_SIZE) LRUCacheShard final : public CacheShard { +class ALIGN_AS(CACHE_LINE_SIZE) LRUCacheShard final : public CacheShardBase { public: LRUCacheShard(size_t capacity, bool strict_capacity_limit, double high_pri_pool_ratio, double low_pri_pool_ratio, bool use_adaptive_mutex, CacheMetadataChargePolicy metadata_charge_policy, - int max_upper_hash_bits, - const std::shared_ptr& secondary_cache); - virtual ~LRUCacheShard() override = default; + int max_upper_hash_bits, SecondaryCache* secondary_cache); + + public: // Type definitions expected as parameter to ShardedCache + using HandleImpl = LRUHandle; + using HashVal = uint32_t; + using HashCref = uint32_t; + + public: // Function definitions expected as parameter to ShardedCache + static inline HashVal ComputeHash(const Slice& key) { + return Lower32of64(GetSliceNPHash64(key)); + } // Separate from constructor so caller can easily make an array of LRUCache // if current usage is more than new capacity, the function will attempt to // free the needed space. - virtual void SetCapacity(size_t capacity) override; + void SetCapacity(size_t capacity); // Set the flag to reject insertion if cache if full. - virtual void SetStrictCapacityLimit(bool strict_capacity_limit) override; + void SetStrictCapacityLimit(bool strict_capacity_limit); // Set percentage of capacity reserved for high-pri cache entries. void SetHighPriorityPoolRatio(double high_pri_pool_ratio); @@ -338,58 +346,49 @@ class ALIGN_AS(CACHE_LINE_SIZE) LRUCacheShard final : public CacheShard { void SetLowPriorityPoolRatio(double low_pri_pool_ratio); // Like Cache methods, but with an extra "hash" parameter. - virtual Status Insert(const Slice& key, uint32_t hash, void* value, - size_t charge, Cache::DeleterFn deleter, - Cache::Handle** handle, - Cache::Priority priority) override { + inline Status Insert(const Slice& key, uint32_t hash, void* value, + size_t charge, Cache::DeleterFn deleter, + LRUHandle** handle, Cache::Priority priority) { return Insert(key, hash, value, charge, deleter, nullptr, handle, priority); } - virtual Status Insert(const Slice& key, uint32_t hash, void* value, - const Cache::CacheItemHelper* helper, size_t charge, - Cache::Handle** handle, - Cache::Priority priority) override { + inline Status Insert(const Slice& key, uint32_t hash, void* value, + const Cache::CacheItemHelper* helper, size_t charge, + LRUHandle** handle, Cache::Priority priority) { assert(helper); return Insert(key, hash, value, charge, nullptr, helper, handle, priority); } // If helper_cb is null, the values of the following arguments don't matter. - virtual Cache::Handle* Lookup(const Slice& key, uint32_t hash, - const ShardedCache::CacheItemHelper* helper, - const ShardedCache::CreateCallback& create_cb, - ShardedCache::Priority priority, bool wait, - Statistics* stats) override; - virtual Cache::Handle* Lookup(const Slice& key, uint32_t hash) override { + LRUHandle* Lookup(const Slice& key, uint32_t hash, + const Cache::CacheItemHelper* helper, + const Cache::CreateCallback& create_cb, + Cache::Priority priority, bool wait, Statistics* stats); + inline LRUHandle* Lookup(const Slice& key, uint32_t hash) { return Lookup(key, hash, nullptr, nullptr, Cache::Priority::LOW, true, nullptr); } - virtual bool Release(Cache::Handle* handle, bool /*useful*/, - bool erase_if_last_ref) override { - return Release(handle, erase_if_last_ref); - } - virtual bool IsReady(Cache::Handle* /*handle*/) override; - virtual void Wait(Cache::Handle* /*handle*/) override {} - virtual bool Ref(Cache::Handle* handle) override; - virtual bool Release(Cache::Handle* handle, - bool erase_if_last_ref = false) override; - virtual void Erase(const Slice& key, uint32_t hash) override; + bool Release(LRUHandle* handle, bool useful, bool erase_if_last_ref); + bool IsReady(LRUHandle* /*handle*/); + void Wait(LRUHandle* /*handle*/) {} + bool Ref(LRUHandle* handle); + void Erase(const Slice& key, uint32_t hash); // Although in some platforms the update of size_t is atomic, to make sure // GetUsage() and GetPinnedUsage() work correctly under any platform, we'll // protect them with mutex_. - virtual size_t GetUsage() const override; - virtual size_t GetPinnedUsage() const override; - virtual size_t GetOccupancyCount() const override; - virtual size_t GetTableAddressCount() const override; + size_t GetUsage() const; + size_t GetPinnedUsage() const; + size_t GetOccupancyCount() const; + size_t GetTableAddressCount() const; - virtual void ApplyToSomeEntries( + void ApplyToSomeEntries( const std::function& callback, - uint32_t average_entries_per_lock, uint32_t* state) override; + size_t average_entries_per_lock, size_t* state); - virtual void EraseUnRefEntries() override; - - virtual std::string GetPrintableOptions() const override; + void EraseUnRefEntries(); + public: // other function definitions void TEST_GetLRUList(LRUHandle** lru, LRUHandle** lru_low_pri, LRUHandle** lru_bottom_pri); @@ -403,17 +402,19 @@ class ALIGN_AS(CACHE_LINE_SIZE) LRUCacheShard final : public CacheShard { // Retrieves low pri pool ratio double GetLowPriPoolRatio(); + void AppendPrintableOptions(std::string& /*str*/) const; + private: friend class LRUCache; // Insert an item into the hash table and, if handle is null, insert into // the LRU list. Older items are evicted as necessary. If the cache is full // and free_handle_on_fail is true, the item is deleted and handle is set to // nullptr. - Status InsertItem(LRUHandle* item, Cache::Handle** handle, + Status InsertItem(LRUHandle* item, LRUHandle** handle, bool free_handle_on_fail); Status Insert(const Slice& key, uint32_t hash, void* value, size_t charge, DeleterFn deleter, const Cache::CacheItemHelper* helper, - Cache::Handle** handle, Cache::Priority priority); + LRUHandle** handle, Cache::Priority priority); // Promote an item looked up from the secondary cache to the LRU cache. // The item may be still in the secondary cache. // It is only inserted into the hash table and not the LRU list, and only @@ -500,14 +501,15 @@ class ALIGN_AS(CACHE_LINE_SIZE) LRUCacheShard final : public CacheShard { // don't mind mutex_ invoking the non-const actions. mutable DMutex mutex_; - std::shared_ptr secondary_cache_; + // Owned by LRUCache + SecondaryCache* secondary_cache_; }; class LRUCache #ifdef NDEBUG final #endif - : public ShardedCache { + : public ShardedCache { public: LRUCache(size_t capacity, int num_shard_bits, bool strict_capacity_limit, double high_pri_pool_ratio, double low_pri_pool_ratio, @@ -515,27 +517,21 @@ class LRUCache bool use_adaptive_mutex = kDefaultToAdaptiveMutex, CacheMetadataChargePolicy metadata_charge_policy = kDontChargeCacheMetadata, - const std::shared_ptr& secondary_cache = nullptr); - virtual ~LRUCache(); - virtual const char* Name() const override { return "LRUCache"; } - virtual CacheShard* GetShard(uint32_t shard) override; - virtual const CacheShard* GetShard(uint32_t shard) const override; - virtual void* Value(Handle* handle) override; - virtual size_t GetCharge(Handle* handle) const override; - virtual uint32_t GetHash(Handle* handle) const override; - virtual DeleterFn GetDeleter(Handle* handle) const override; - virtual void DisownData() override; - virtual void WaitAll(std::vector& handles) override; - std::string GetPrintableOptions() const override; + std::shared_ptr secondary_cache = nullptr); + const char* Name() const override { return "LRUCache"; } + void* Value(Handle* handle) override; + size_t GetCharge(Handle* handle) const override; + DeleterFn GetDeleter(Handle* handle) const override; + void WaitAll(std::vector& handles) override; // Retrieves number of elements in LRU, for unit test purpose only. size_t TEST_GetLRUSize(); // Retrieves high pri pool ratio. double GetHighPriPoolRatio(); + void AppendPrintableOptions(std::string& str) const override; + private: - LRUCacheShard* shards_ = nullptr; - int num_shards_ = 0; std::shared_ptr secondary_cache_; }; diff --git a/cache/lru_cache_test.cc b/cache/lru_cache_test.cc index 748908d0c..fbf336f87 100644 --- a/cache/lru_cache_test.cc +++ b/cache/lru_cache_test.cc @@ -67,7 +67,7 @@ class LRUCacheTest : public testing::Test { bool Lookup(const std::string& key) { auto handle = cache_->Lookup(key, 0 /*hash*/); if (handle) { - cache_->Release(handle); + cache_->Release(handle, true /*useful*/, false /*erase*/); return true; } return false; @@ -529,22 +529,27 @@ class ClockCacheTest : public testing::Test { kDontChargeCacheMetadata); } - Status Insert(const std::string& key, + Status Insert(const UniqueId64x2& hashed_key, Cache::Priority priority = Cache::Priority::LOW) { - return shard_->Insert(key, 0 /*hash*/, nullptr /*value*/, 1 /*charge*/, - nullptr /*deleter*/, nullptr /*handle*/, priority); + return shard_->Insert(TestKey(hashed_key), hashed_key, nullptr /*value*/, + 1 /*charge*/, nullptr /*deleter*/, nullptr /*handle*/, + priority); } Status Insert(char key, Cache::Priority priority = Cache::Priority::LOW) { - return Insert(std::string(kCacheKeySize, key), priority); + return Insert(TestHashedKey(key), priority); } Status InsertWithLen(char key, size_t len) { - return Insert(std::string(len, key)); + std::string skey(len, key); + return shard_->Insert(skey, TestHashedKey(key), nullptr /*value*/, + 1 /*charge*/, nullptr /*deleter*/, nullptr /*handle*/, + Cache::Priority::LOW); } - bool Lookup(const std::string& key, bool useful = true) { - auto handle = shard_->Lookup(key, 0 /*hash*/); + bool Lookup(const Slice& key, const UniqueId64x2& hashed_key, + bool useful = true) { + auto handle = shard_->Lookup(key, hashed_key); if (handle) { shard_->Release(handle, useful, /*erase_if_last_ref=*/false); return true; @@ -552,43 +557,28 @@ class ClockCacheTest : public testing::Test { return false; } - bool Lookup(char key, bool useful = true) { - return Lookup(std::string(kCacheKeySize, key), useful); + bool Lookup(const UniqueId64x2& hashed_key, bool useful = true) { + return Lookup(TestKey(hashed_key), hashed_key, useful); } - void Erase(const std::string& key) { shard_->Erase(key, 0 /*hash*/); } - -#if 0 // FIXME - size_t CalcEstimatedHandleChargeWrapper( - size_t estimated_value_size, - CacheMetadataChargePolicy metadata_charge_policy) { - return ClockCacheShard::CalcEstimatedHandleCharge(estimated_value_size, - metadata_charge_policy); + bool Lookup(char key, bool useful = true) { + return Lookup(TestHashedKey(key), useful); } - int CalcHashBitsWrapper(size_t capacity, size_t estimated_value_size, - CacheMetadataChargePolicy metadata_charge_policy) { - return ClockCacheShard::CalcHashBits(capacity, estimated_value_size, - metadata_charge_policy); + void Erase(char key) { + UniqueId64x2 hashed_key = TestHashedKey(key); + shard_->Erase(TestKey(hashed_key), hashed_key); } - // Maximum number of items that a shard can hold. - double CalcMaxOccupancy(size_t capacity, size_t estimated_value_size, - CacheMetadataChargePolicy metadata_charge_policy) { - size_t handle_charge = ClockCacheShard::CalcEstimatedHandleCharge( - estimated_value_size, metadata_charge_policy); - return capacity / (kLoadFactor * handle_charge); + static inline Slice TestKey(const UniqueId64x2& hashed_key) { + return Slice(reinterpret_cast(&hashed_key), 16U); } - bool TableSizeIsAppropriate(int hash_bits, double max_occupancy) { - if (hash_bits == 0) { - return max_occupancy <= 1; - } else { - return (1 << hash_bits >= max_occupancy) && - (1 << (hash_bits - 1) <= max_occupancy); - } + static inline UniqueId64x2 TestHashedKey(char key) { + // For testing hash near-collision behavior, put the variance in + // hashed_key in bits that are unlikely to be used as hash bits. + return {(static_cast(key) << 56) + 1234U, 5678U}; } -#endif ClockCacheShard* shard_ = nullptr; }; @@ -607,10 +597,10 @@ TEST_F(ClockCacheTest, Misc) { // Some of this is motivated by code coverage std::string wrong_size_key(15, 'x'); - EXPECT_FALSE(Lookup(wrong_size_key)); + EXPECT_FALSE(Lookup(wrong_size_key, TestHashedKey('x'))); EXPECT_FALSE(shard_->Ref(nullptr)); EXPECT_FALSE(shard_->Release(nullptr)); - shard_->Erase(wrong_size_key, /*hash*/ 42); // no-op + shard_->Erase(wrong_size_key, TestHashedKey('x')); // no-op } TEST_F(ClockCacheTest, Limits) { @@ -622,11 +612,11 @@ TEST_F(ClockCacheTest, Limits) { // Also tests switching between strict limit and not shard_->SetStrictCapacityLimit(strict_capacity_limit); - std::string key(16, 'x'); + UniqueId64x2 hkey = TestHashedKey('x'); // Single entry charge beyond capacity { - Status s = shard_->Insert(key, 0 /*hash*/, nullptr /*value*/, + Status s = shard_->Insert(TestKey(hkey), hkey, nullptr /*value*/, 5 /*charge*/, nullptr /*deleter*/, nullptr /*handle*/, Cache::Priority::LOW); if (strict_capacity_limit) { @@ -638,9 +628,10 @@ TEST_F(ClockCacheTest, Limits) { // Single entry fills capacity { - Cache::Handle* h; - ASSERT_OK(shard_->Insert(key, 0 /*hash*/, nullptr /*value*/, 3 /*charge*/, - nullptr /*deleter*/, &h, Cache::Priority::LOW)); + ClockHandle* h; + ASSERT_OK(shard_->Insert(TestKey(hkey), hkey, nullptr /*value*/, + 3 /*charge*/, nullptr /*deleter*/, &h, + Cache::Priority::LOW)); // Try to insert more Status s = Insert('a'); if (strict_capacity_limit) { @@ -657,11 +648,11 @@ TEST_F(ClockCacheTest, Limits) { // entries) to exceed occupancy limit. { size_t n = shard_->GetTableAddressCount() + 1; - std::unique_ptr ha { new Cache::Handle* [n] {} }; + std::unique_ptr ha { new ClockHandle* [n] {} }; Status s; for (size_t i = 0; i < n && s.ok(); ++i) { - EncodeFixed64(&key[0], i); - s = shard_->Insert(key, 0 /*hash*/, nullptr /*value*/, 0 /*charge*/, + hkey[1] = i; + s = shard_->Insert(TestKey(hkey), hkey, nullptr /*value*/, 0 /*charge*/, nullptr /*deleter*/, &ha[i], Cache::Priority::LOW); if (i == 0) { EXPECT_OK(s); @@ -807,12 +798,11 @@ void IncrementIntDeleter(const Slice& /*key*/, void* value) { // Testing calls to CorrectNearOverflow in Release TEST_F(ClockCacheTest, ClockCounterOverflowTest) { NewShard(6, /*strict_capacity_limit*/ false); - Cache::Handle* h; + ClockHandle* h; int deleted = 0; - std::string my_key(kCacheKeySize, 'x'); - uint32_t my_hash = 42; - ASSERT_OK(shard_->Insert(my_key, my_hash, &deleted, 1, IncrementIntDeleter, - &h, Cache::Priority::HIGH)); + UniqueId64x2 hkey = TestHashedKey('x'); + ASSERT_OK(shard_->Insert(TestKey(hkey), hkey, &deleted, 1, + IncrementIntDeleter, &h, Cache::Priority::HIGH)); // Some large number outstanding shard_->TEST_RefN(h, 123456789); @@ -822,7 +812,7 @@ TEST_F(ClockCacheTest, ClockCounterOverflowTest) { shard_->TEST_ReleaseN(h, 1234567); } // Mark it invisible (to reach a different CorrectNearOverflow() in Release) - shard_->Erase(my_key, my_hash); + shard_->Erase(TestKey(hkey), hkey); // Simulate many more lookup/ref + release (one-by-one would be too // expensive for unit test) for (int i = 0; i < 10000; ++i) { @@ -844,63 +834,65 @@ TEST_F(ClockCacheTest, ClockCounterOverflowTest) { TEST_F(ClockCacheTest, CollidingInsertEraseTest) { NewShard(6, /*strict_capacity_limit*/ false); int deleted = 0; - std::string key1(kCacheKeySize, 'x'); - std::string key2(kCacheKeySize, 'y'); - std::string key3(kCacheKeySize, 'z'); - uint32_t my_hash = 42; - Cache::Handle* h1; - ASSERT_OK(shard_->Insert(key1, my_hash, &deleted, 1, IncrementIntDeleter, &h1, + UniqueId64x2 hkey1 = TestHashedKey('x'); + Slice key1 = TestKey(hkey1); + UniqueId64x2 hkey2 = TestHashedKey('y'); + Slice key2 = TestKey(hkey2); + UniqueId64x2 hkey3 = TestHashedKey('z'); + Slice key3 = TestKey(hkey3); + ClockHandle* h1; + ASSERT_OK(shard_->Insert(key1, hkey1, &deleted, 1, IncrementIntDeleter, &h1, Cache::Priority::HIGH)); - Cache::Handle* h2; - ASSERT_OK(shard_->Insert(key2, my_hash, &deleted, 1, IncrementIntDeleter, &h2, + ClockHandle* h2; + ASSERT_OK(shard_->Insert(key2, hkey2, &deleted, 1, IncrementIntDeleter, &h2, Cache::Priority::HIGH)); - Cache::Handle* h3; - ASSERT_OK(shard_->Insert(key3, my_hash, &deleted, 1, IncrementIntDeleter, &h3, + ClockHandle* h3; + ASSERT_OK(shard_->Insert(key3, hkey3, &deleted, 1, IncrementIntDeleter, &h3, Cache::Priority::HIGH)); // Can repeatedly lookup+release despite the hash collision - Cache::Handle* tmp_h; + ClockHandle* tmp_h; for (bool erase_if_last_ref : {true, false}) { // but not last ref - tmp_h = shard_->Lookup(key1, my_hash); + tmp_h = shard_->Lookup(key1, hkey1); ASSERT_EQ(h1, tmp_h); ASSERT_FALSE(shard_->Release(tmp_h, erase_if_last_ref)); - tmp_h = shard_->Lookup(key2, my_hash); + tmp_h = shard_->Lookup(key2, hkey2); ASSERT_EQ(h2, tmp_h); ASSERT_FALSE(shard_->Release(tmp_h, erase_if_last_ref)); - tmp_h = shard_->Lookup(key3, my_hash); + tmp_h = shard_->Lookup(key3, hkey3); ASSERT_EQ(h3, tmp_h); ASSERT_FALSE(shard_->Release(tmp_h, erase_if_last_ref)); } // Make h1 invisible - shard_->Erase(key1, my_hash); + shard_->Erase(key1, hkey1); // Redundant erase - shard_->Erase(key1, my_hash); + shard_->Erase(key1, hkey1); // All still alive ASSERT_EQ(deleted, 0); // Invisible to Lookup - tmp_h = shard_->Lookup(key1, my_hash); + tmp_h = shard_->Lookup(key1, hkey1); ASSERT_EQ(nullptr, tmp_h); // Can still find h2, h3 for (bool erase_if_last_ref : {true, false}) { // but not last ref - tmp_h = shard_->Lookup(key2, my_hash); + tmp_h = shard_->Lookup(key2, hkey2); ASSERT_EQ(h2, tmp_h); ASSERT_FALSE(shard_->Release(tmp_h, erase_if_last_ref)); - tmp_h = shard_->Lookup(key3, my_hash); + tmp_h = shard_->Lookup(key3, hkey3); ASSERT_EQ(h3, tmp_h); ASSERT_FALSE(shard_->Release(tmp_h, erase_if_last_ref)); } // Also Insert with invisible entry there - ASSERT_OK(shard_->Insert(key1, my_hash, &deleted, 1, IncrementIntDeleter, + ASSERT_OK(shard_->Insert(key1, hkey1, &deleted, 1, IncrementIntDeleter, nullptr, Cache::Priority::HIGH)); - tmp_h = shard_->Lookup(key1, my_hash); + tmp_h = shard_->Lookup(key1, hkey1); // Found but distinct handle ASSERT_NE(nullptr, tmp_h); ASSERT_NE(h1, tmp_h); @@ -918,11 +910,11 @@ TEST_F(ClockCacheTest, CollidingInsertEraseTest) { // Can still find h2, h3 for (bool erase_if_last_ref : {true, false}) { // but not last ref - tmp_h = shard_->Lookup(key2, my_hash); + tmp_h = shard_->Lookup(key2, hkey2); ASSERT_EQ(h2, tmp_h); ASSERT_FALSE(shard_->Release(tmp_h, erase_if_last_ref)); - tmp_h = shard_->Lookup(key3, my_hash); + tmp_h = shard_->Lookup(key3, hkey3); ASSERT_EQ(h3, tmp_h); ASSERT_FALSE(shard_->Release(tmp_h, erase_if_last_ref)); } @@ -934,7 +926,7 @@ TEST_F(ClockCacheTest, CollidingInsertEraseTest) { ASSERT_EQ(deleted, 0); // Can still find it - tmp_h = shard_->Lookup(key2, my_hash); + tmp_h = shard_->Lookup(key2, hkey2); ASSERT_EQ(h2, tmp_h); // Release last ref on h2, with erase @@ -942,12 +934,12 @@ TEST_F(ClockCacheTest, CollidingInsertEraseTest) { // h2 deleted ASSERT_EQ(deleted--, 1); - tmp_h = shard_->Lookup(key2, my_hash); + tmp_h = shard_->Lookup(key2, hkey2); ASSERT_EQ(nullptr, tmp_h); // Can still find h3 for (bool erase_if_last_ref : {true, false}) { // but not last ref - tmp_h = shard_->Lookup(key3, my_hash); + tmp_h = shard_->Lookup(key3, hkey3); ASSERT_EQ(h3, tmp_h); ASSERT_FALSE(shard_->Release(tmp_h, erase_if_last_ref)); } @@ -959,11 +951,11 @@ TEST_F(ClockCacheTest, CollidingInsertEraseTest) { ASSERT_EQ(deleted, 0); // Explicit erase - shard_->Erase(key3, my_hash); + shard_->Erase(key3, hkey3); // h3 deleted ASSERT_EQ(deleted--, 1); - tmp_h = shard_->Lookup(key3, my_hash); + tmp_h = shard_->Lookup(key3, hkey3); ASSERT_EQ(nullptr, tmp_h); } @@ -1371,9 +1363,11 @@ TEST_F(LRUCacheSecondaryCacheTest, SaveFailTest) { std::string str2 = rnd.RandomString(1020); TestItem* item2 = new TestItem(str2.data(), str2.length()); // k1 should be demoted to NVM + ASSERT_EQ(secondary_cache->num_inserts(), 0u); ASSERT_OK(cache->Insert(k2.AsSlice(), item2, &LRUCacheSecondaryCacheTest::helper_fail_, str2.length())); + ASSERT_EQ(secondary_cache->num_inserts(), 1u); Cache::Handle* handle; handle = diff --git a/cache/sharded_cache.cc b/cache/sharded_cache.cc index 3e6d6a4f7..9ebca3ba8 100644 --- a/cache/sharded_cache.cc +++ b/cache/sharded_cache.cc @@ -19,184 +19,49 @@ namespace ROCKSDB_NAMESPACE { -namespace { - -inline uint32_t HashSlice(const Slice& s) { - return Lower32of64(GetSliceNPHash64(s)); -} - -} // namespace - -ShardedCache::ShardedCache(size_t capacity, int num_shard_bits, - bool strict_capacity_limit, - std::shared_ptr allocator) +ShardedCacheBase::ShardedCacheBase(size_t capacity, int num_shard_bits, + bool strict_capacity_limit, + std::shared_ptr allocator) : Cache(std::move(allocator)), + last_id_(1), shard_mask_((uint32_t{1} << num_shard_bits) - 1), - capacity_(capacity), strict_capacity_limit_(strict_capacity_limit), - last_id_(1) {} + capacity_(capacity) {} -void ShardedCache::SetCapacity(size_t capacity) { +size_t ShardedCacheBase::ComputePerShardCapacity(size_t capacity) const { uint32_t num_shards = GetNumShards(); - const size_t per_shard = (capacity + (num_shards - 1)) / num_shards; - MutexLock l(&capacity_mutex_); - for (uint32_t s = 0; s < num_shards; s++) { - GetShard(s)->SetCapacity(per_shard); - } - capacity_ = capacity; -} - -void ShardedCache::SetStrictCapacityLimit(bool strict_capacity_limit) { - uint32_t num_shards = GetNumShards(); - MutexLock l(&capacity_mutex_); - for (uint32_t s = 0; s < num_shards; s++) { - GetShard(s)->SetStrictCapacityLimit(strict_capacity_limit); - } - strict_capacity_limit_ = strict_capacity_limit; -} - -Status ShardedCache::Insert(const Slice& key, void* value, size_t charge, - DeleterFn deleter, Handle** handle, - Priority priority) { - uint32_t hash = HashSlice(key); - return GetShard(Shard(hash)) - ->Insert(key, hash, value, charge, deleter, handle, priority); -} - -Status ShardedCache::Insert(const Slice& key, void* value, - const CacheItemHelper* helper, size_t charge, - Handle** handle, Priority priority) { - uint32_t hash = HashSlice(key); - if (!helper) { - return Status::InvalidArgument(); - } - return GetShard(Shard(hash)) - ->Insert(key, hash, value, helper, charge, handle, priority); -} - -Cache::Handle* ShardedCache::Lookup(const Slice& key, Statistics* /*stats*/) { - uint32_t hash = HashSlice(key); - return GetShard(Shard(hash))->Lookup(key, hash); -} - -Cache::Handle* ShardedCache::Lookup(const Slice& key, - const CacheItemHelper* helper, - const CreateCallback& create_cb, - Priority priority, bool wait, - Statistics* stats) { - uint32_t hash = HashSlice(key); - return GetShard(Shard(hash)) - ->Lookup(key, hash, helper, create_cb, priority, wait, stats); -} - -bool ShardedCache::IsReady(Handle* handle) { - uint32_t hash = GetHash(handle); - return GetShard(Shard(hash))->IsReady(handle); -} - -void ShardedCache::Wait(Handle* handle) { - uint32_t hash = GetHash(handle); - GetShard(Shard(hash))->Wait(handle); -} - -bool ShardedCache::Ref(Handle* handle) { - uint32_t hash = GetHash(handle); - return GetShard(Shard(hash))->Ref(handle); -} - -bool ShardedCache::Release(Handle* handle, bool erase_if_last_ref) { - uint32_t hash = GetHash(handle); - return GetShard(Shard(hash))->Release(handle, erase_if_last_ref); + return (capacity + (num_shards - 1)) / num_shards; } -bool ShardedCache::Release(Handle* handle, bool useful, - bool erase_if_last_ref) { - uint32_t hash = GetHash(handle); - return GetShard(Shard(hash))->Release(handle, useful, erase_if_last_ref); +size_t ShardedCacheBase::GetPerShardCapacity() const { + return ComputePerShardCapacity(GetCapacity()); } -void ShardedCache::Erase(const Slice& key) { - uint32_t hash = HashSlice(key); - GetShard(Shard(hash))->Erase(key, hash); -} - -uint64_t ShardedCache::NewId() { +uint64_t ShardedCacheBase::NewId() { return last_id_.fetch_add(1, std::memory_order_relaxed); } -size_t ShardedCache::GetCapacity() const { - MutexLock l(&capacity_mutex_); +size_t ShardedCacheBase::GetCapacity() const { + MutexLock l(&config_mutex_); return capacity_; } -bool ShardedCache::HasStrictCapacityLimit() const { - MutexLock l(&capacity_mutex_); +bool ShardedCacheBase::HasStrictCapacityLimit() const { + MutexLock l(&config_mutex_); return strict_capacity_limit_; } -size_t ShardedCache::GetUsage() const { - // We will not lock the cache when getting the usage from shards. - uint32_t num_shards = GetNumShards(); - size_t usage = 0; - for (uint32_t s = 0; s < num_shards; s++) { - usage += GetShard(s)->GetUsage(); - } - return usage; -} - -size_t ShardedCache::GetUsage(Handle* handle) const { +size_t ShardedCacheBase::GetUsage(Handle* handle) const { return GetCharge(handle); } -size_t ShardedCache::GetPinnedUsage() const { - // We will not lock the cache when getting the usage from shards. - uint32_t num_shards = GetNumShards(); - size_t usage = 0; - for (uint32_t s = 0; s < num_shards; s++) { - usage += GetShard(s)->GetPinnedUsage(); - } - return usage; -} - -void ShardedCache::ApplyToAllEntries( - const std::function& callback, - const ApplyToAllEntriesOptions& opts) { - uint32_t num_shards = GetNumShards(); - // Iterate over part of each shard, rotating between shards, to - // minimize impact on latency of concurrent operations. - std::unique_ptr states(new uint32_t[num_shards]{}); - - uint32_t aepl_in_32 = static_cast( - std::min(size_t{UINT32_MAX}, opts.average_entries_per_lock)); - aepl_in_32 = std::min(aepl_in_32, uint32_t{1}); - - bool remaining_work; - do { - remaining_work = false; - for (uint32_t s = 0; s < num_shards; s++) { - if (states[s] != UINT32_MAX) { - GetShard(s)->ApplyToSomeEntries(callback, aepl_in_32, &states[s]); - remaining_work |= states[s] != UINT32_MAX; - } - } - } while (remaining_work); -} - -void ShardedCache::EraseUnRefEntries() { - uint32_t num_shards = GetNumShards(); - for (uint32_t s = 0; s < num_shards; s++) { - GetShard(s)->EraseUnRefEntries(); - } -} - -std::string ShardedCache::GetPrintableOptions() const { +std::string ShardedCacheBase::GetPrintableOptions() const { std::string ret; ret.reserve(20000); const int kBufferSize = 200; char buffer[kBufferSize]; { - MutexLock l(&capacity_mutex_); + MutexLock l(&config_mutex_); snprintf(buffer, kBufferSize, " capacity : %" ROCKSDB_PRIszt "\n", capacity_); ret.append(buffer); @@ -210,7 +75,7 @@ std::string ShardedCache::GetPrintableOptions() const { snprintf(buffer, kBufferSize, " memory_allocator : %s\n", memory_allocator() ? memory_allocator()->Name() : "None"); ret.append(buffer); - ret.append(GetShard(0)->GetPrintableOptions()); + AppendPrintableOptions(ret); return ret; } @@ -226,25 +91,10 @@ int GetDefaultCacheShardBits(size_t capacity, size_t min_shard_size) { return num_shard_bits; } -int ShardedCache::GetNumShardBits() const { return BitsSetToOne(shard_mask_); } - -uint32_t ShardedCache::GetNumShards() const { return shard_mask_ + 1; } - -size_t ShardedCache::GetOccupancyCount() const { - size_t oc = 0; - uint32_t num_shards = GetNumShards(); - for (uint32_t s = 0; s < num_shards; s++) { - oc += GetShard(s)->GetOccupancyCount(); - } - return oc; -} -size_t ShardedCache::GetTableAddressCount() const { - size_t tac = 0; - uint32_t num_shards = GetNumShards(); - for (uint32_t s = 0; s < num_shards; s++) { - tac += GetShard(s)->GetTableAddressCount(); - } - return tac; +int ShardedCacheBase::GetNumShardBits() const { + return BitsSetToOne(shard_mask_); } +uint32_t ShardedCacheBase::GetNumShards() const { return shard_mask_ + 1; } + } // namespace ROCKSDB_NAMESPACE diff --git a/cache/sharded_cache.h b/cache/sharded_cache.h index 8713d1dce..e3271cc7b 100644 --- a/cache/sharded_cache.h +++ b/cache/sharded_cache.h @@ -10,122 +10,309 @@ #pragma once #include +#include #include +#include "port/lang.h" #include "port/port.h" #include "rocksdb/cache.h" +#include "util/hash.h" +#include "util/mutexlock.h" namespace ROCKSDB_NAMESPACE { -// Single cache shard interface. -class CacheShard { +// Optional base class for classes implementing the CacheShard concept +class CacheShardBase { public: - explicit CacheShard(CacheMetadataChargePolicy metadata_charge_policy) + explicit CacheShardBase(CacheMetadataChargePolicy metadata_charge_policy) : metadata_charge_policy_(metadata_charge_policy) {} - virtual ~CacheShard() = default; using DeleterFn = Cache::DeleterFn; - virtual Status Insert(const Slice& key, uint32_t hash, void* value, - size_t charge, DeleterFn deleter, - Cache::Handle** handle, Cache::Priority priority) = 0; - virtual Status Insert(const Slice& key, uint32_t hash, void* value, - const Cache::CacheItemHelper* helper, size_t charge, - Cache::Handle** handle, Cache::Priority priority) = 0; - virtual Cache::Handle* Lookup(const Slice& key, uint32_t hash) = 0; - virtual Cache::Handle* Lookup(const Slice& key, uint32_t hash, - const Cache::CacheItemHelper* helper, - const Cache::CreateCallback& create_cb, - Cache::Priority priority, bool wait, - Statistics* stats) = 0; - virtual bool Release(Cache::Handle* handle, bool useful, - bool erase_if_last_ref) = 0; - virtual bool IsReady(Cache::Handle* handle) = 0; - virtual void Wait(Cache::Handle* handle) = 0; - virtual bool Ref(Cache::Handle* handle) = 0; - virtual bool Release(Cache::Handle* handle, bool erase_if_last_ref) = 0; - virtual void Erase(const Slice& key, uint32_t hash) = 0; - virtual void SetCapacity(size_t capacity) = 0; - virtual void SetStrictCapacityLimit(bool strict_capacity_limit) = 0; - virtual size_t GetUsage() const = 0; - virtual size_t GetPinnedUsage() const = 0; - virtual size_t GetOccupancyCount() const = 0; - virtual size_t GetTableAddressCount() const = 0; + + // Expected by concept CacheShard (TODO with C++20 support) + // Some Defaults + std::string GetPrintableOptions() const { return ""; } + using HashVal = uint64_t; + using HashCref = uint64_t; + static inline HashVal ComputeHash(const Slice& key) { + return GetSliceNPHash64(key); + } + static inline uint32_t HashPieceForSharding(HashCref hash) { + return Lower32of64(hash); + } + void AppendPrintableOptions(std::string& /*str*/) const {} + + // Must be provided for concept CacheShard (TODO with C++20 support) + /* + struct HandleImpl { // for concept HandleImpl + HashVal hash; + HashCref GetHash() const; + ... + }; + Status Insert(const Slice& key, HashCref hash, void* value, size_t charge, + DeleterFn deleter, HandleImpl** handle, + Cache::Priority priority) = 0; + Status Insert(const Slice& key, HashCref hash, void* value, + const Cache::CacheItemHelper* helper, size_t charge, + HandleImpl** handle, Cache::Priority priority) = 0; + HandleImpl* Lookup(const Slice& key, HashCref hash) = 0; + HandleImpl* Lookup(const Slice& key, HashCref hash, + const Cache::CacheItemHelper* helper, + const Cache::CreateCallback& create_cb, + Cache::Priority priority, bool wait, + Statistics* stats) = 0; + bool Release(HandleImpl* handle, bool useful, bool erase_if_last_ref) = 0; + bool IsReady(HandleImpl* handle) = 0; + void Wait(HandleImpl* handle) = 0; + bool Ref(HandleImpl* handle) = 0; + void Erase(const Slice& key, HashCref hash) = 0; + void SetCapacity(size_t capacity) = 0; + void SetStrictCapacityLimit(bool strict_capacity_limit) = 0; + size_t GetUsage() const = 0; + size_t GetPinnedUsage() const = 0; + size_t GetOccupancyCount() const = 0; + size_t GetTableAddressCount() const = 0; // Handles iterating over roughly `average_entries_per_lock` entries, using // `state` to somehow record where it last ended up. Caller initially uses - // *state == 0 and implementation sets *state = UINT32_MAX to indicate + // *state == 0 and implementation sets *state = SIZE_MAX to indicate // completion. - virtual void ApplyToSomeEntries( + void ApplyToSomeEntries( const std::function& callback, - uint32_t average_entries_per_lock, uint32_t* state) = 0; - virtual void EraseUnRefEntries() = 0; - virtual std::string GetPrintableOptions() const { return ""; } + size_t average_entries_per_lock, size_t* state) = 0; + void EraseUnRefEntries() = 0; + */ protected: const CacheMetadataChargePolicy metadata_charge_policy_; }; -// Generic cache interface which shards cache by hash of keys. 2^num_shard_bits +// Portions of ShardedCache that do not depend on the template parameter +class ShardedCacheBase : public Cache { + public: + ShardedCacheBase(size_t capacity, int num_shard_bits, + bool strict_capacity_limit, + std::shared_ptr memory_allocator); + virtual ~ShardedCacheBase() = default; + + int GetNumShardBits() const; + uint32_t GetNumShards() const; + + uint64_t NewId() override; + + bool HasStrictCapacityLimit() const override; + size_t GetCapacity() const override; + + using Cache::GetUsage; + size_t GetUsage(Handle* handle) const override; + std::string GetPrintableOptions() const override; + + protected: // fns + virtual void AppendPrintableOptions(std::string& str) const = 0; + size_t GetPerShardCapacity() const; + size_t ComputePerShardCapacity(size_t capacity) const; + + protected: // data + std::atomic last_id_; // For NewId + const uint32_t shard_mask_; + + // Dynamic configuration parameters, guarded by config_mutex_ + bool strict_capacity_limit_; + size_t capacity_; + mutable port::Mutex config_mutex_; +}; + +// Generic cache interface that shards cache by hash of keys. 2^num_shard_bits // shards will be created, with capacity split evenly to each of the shards. -// Keys are sharded by the highest num_shard_bits bits of hash value. -class ShardedCache : public Cache { +// Keys are typically sharded by the lowest num_shard_bits bits of hash value +// so that the upper bits of the hash value can keep a stable ordering of +// table entries even as the table grows (using more upper hash bits). +// See CacheShardBase above for what is expected of the CacheShard parameter. +template +class ShardedCache : public ShardedCacheBase { public: + using HashVal = typename CacheShard::HashVal; + using HashCref = typename CacheShard::HashCref; + using HandleImpl = typename CacheShard::HandleImpl; + ShardedCache(size_t capacity, int num_shard_bits, bool strict_capacity_limit, - std::shared_ptr memory_allocator = nullptr); - virtual ~ShardedCache() = default; - virtual CacheShard* GetShard(uint32_t shard) = 0; - virtual const CacheShard* GetShard(uint32_t shard) const = 0; - - virtual uint32_t GetHash(Handle* handle) const = 0; - - virtual void SetCapacity(size_t capacity) override; - virtual void SetStrictCapacityLimit(bool strict_capacity_limit) override; - - virtual Status Insert(const Slice& key, void* value, size_t charge, - DeleterFn deleter, Handle** handle, - Priority priority) override; - virtual Status Insert(const Slice& key, void* value, - const CacheItemHelper* helper, size_t charge, - Handle** handle = nullptr, - Priority priority = Priority::LOW) override; - virtual Handle* Lookup(const Slice& key, Statistics* stats) override; - virtual Handle* Lookup(const Slice& key, const CacheItemHelper* helper, - const CreateCallback& create_cb, Priority priority, - bool wait, Statistics* stats = nullptr) override; - virtual bool Release(Handle* handle, bool useful, - bool erase_if_last_ref = false) override; - virtual bool IsReady(Handle* handle) override; - virtual void Wait(Handle* handle) override; - virtual bool Ref(Handle* handle) override; - virtual bool Release(Handle* handle, bool erase_if_last_ref = false) override; - virtual void Erase(const Slice& key) override; - virtual uint64_t NewId() override; - virtual size_t GetCapacity() const override; - virtual bool HasStrictCapacityLimit() const override; - virtual size_t GetUsage() const override; - virtual size_t GetUsage(Handle* handle) const override; - virtual size_t GetPinnedUsage() const override; - virtual size_t GetOccupancyCount() const override; - virtual size_t GetTableAddressCount() const override; - virtual void ApplyToAllEntries( + std::shared_ptr allocator) + : ShardedCacheBase(capacity, num_shard_bits, strict_capacity_limit, + allocator), + shards_(reinterpret_cast(port::cacheline_aligned_alloc( + sizeof(CacheShard) * GetNumShards()))), + destroy_shards_in_dtor_(false) {} + + virtual ~ShardedCache() { + if (destroy_shards_in_dtor_) { + ForEachShard([](CacheShard* cs) { cs->~CacheShard(); }); + } + port::cacheline_aligned_free(shards_); + } + + CacheShard& GetShard(HashCref hash) { + return shards_[CacheShard::HashPieceForSharding(hash) & shard_mask_]; + } + + const CacheShard& GetShard(HashCref hash) const { + return shards_[CacheShard::HashPieceForSharding(hash) & shard_mask_]; + } + + void SetCapacity(size_t capacity) override { + MutexLock l(&config_mutex_); + capacity_ = capacity; + auto per_shard = ComputePerShardCapacity(capacity); + ForEachShard([=](CacheShard* cs) { cs->SetCapacity(per_shard); }); + } + + void SetStrictCapacityLimit(bool s_c_l) override { + MutexLock l(&config_mutex_); + strict_capacity_limit_ = s_c_l; + ForEachShard( + [s_c_l](CacheShard* cs) { cs->SetStrictCapacityLimit(s_c_l); }); + } + + Status Insert(const Slice& key, void* value, size_t charge, DeleterFn deleter, + Handle** handle, Priority priority) override { + HashVal hash = CacheShard::ComputeHash(key); + auto h_out = reinterpret_cast(handle); + return GetShard(hash).Insert(key, hash, value, charge, deleter, h_out, + priority); + } + Status Insert(const Slice& key, void* value, const CacheItemHelper* helper, + size_t charge, Handle** handle = nullptr, + Priority priority = Priority::LOW) override { + if (!helper) { + return Status::InvalidArgument(); + } + HashVal hash = CacheShard::ComputeHash(key); + auto h_out = reinterpret_cast(handle); + return GetShard(hash).Insert(key, hash, value, helper, charge, h_out, + priority); + } + + Handle* Lookup(const Slice& key, Statistics* /*stats*/) override { + HashVal hash = CacheShard::ComputeHash(key); + HandleImpl* result = GetShard(hash).Lookup(key, hash); + return reinterpret_cast(result); + } + Handle* Lookup(const Slice& key, const CacheItemHelper* helper, + const CreateCallback& create_cb, Priority priority, bool wait, + Statistics* stats = nullptr) override { + HashVal hash = CacheShard::ComputeHash(key); + HandleImpl* result = GetShard(hash).Lookup(key, hash, helper, create_cb, + priority, wait, stats); + return reinterpret_cast(result); + } + + void Erase(const Slice& key) override { + HashVal hash = CacheShard::ComputeHash(key); + GetShard(hash).Erase(key, hash); + } + + bool Release(Handle* handle, bool useful, + bool erase_if_last_ref = false) override { + auto h = reinterpret_cast(handle); + return GetShard(h->GetHash()).Release(h, useful, erase_if_last_ref); + } + bool IsReady(Handle* handle) override { + auto h = reinterpret_cast(handle); + return GetShard(h->GetHash()).IsReady(h); + } + void Wait(Handle* handle) override { + auto h = reinterpret_cast(handle); + GetShard(h->GetHash()).Wait(h); + } + bool Ref(Handle* handle) override { + auto h = reinterpret_cast(handle); + return GetShard(h->GetHash()).Ref(h); + } + bool Release(Handle* handle, bool erase_if_last_ref = false) override { + return Release(handle, true /*useful*/, erase_if_last_ref); + } + using ShardedCacheBase::GetUsage; + size_t GetUsage() const override { + return SumOverShards2(&CacheShard::GetUsage); + } + size_t GetPinnedUsage() const override { + return SumOverShards2(&CacheShard::GetPinnedUsage); + } + size_t GetOccupancyCount() const override { + return SumOverShards2(&CacheShard::GetPinnedUsage); + } + size_t GetTableAddressCount() const override { + return SumOverShards2(&CacheShard::GetTableAddressCount); + } + void ApplyToAllEntries( const std::function& callback, - const ApplyToAllEntriesOptions& opts) override; - virtual void EraseUnRefEntries() override; - virtual std::string GetPrintableOptions() const override; + const ApplyToAllEntriesOptions& opts) override { + uint32_t num_shards = GetNumShards(); + // Iterate over part of each shard, rotating between shards, to + // minimize impact on latency of concurrent operations. + std::unique_ptr states(new size_t[num_shards]{}); - int GetNumShardBits() const; - uint32_t GetNumShards() const; + size_t aepl = opts.average_entries_per_lock; + aepl = std::min(aepl, size_t{1}); + + bool remaining_work; + do { + remaining_work = false; + for (uint32_t i = 0; i < num_shards; i++) { + if (states[i] != SIZE_MAX) { + shards_[i].ApplyToSomeEntries(callback, aepl, &states[i]); + remaining_work |= states[i] != SIZE_MAX; + } + } + } while (remaining_work); + } + + virtual void EraseUnRefEntries() override { + ForEachShard([](CacheShard* cs) { cs->EraseUnRefEntries(); }); + } + + void DisownData() override { + // Leak data only if that won't generate an ASAN/valgrind warning. + if (!kMustFreeHeapAllocations) { + destroy_shards_in_dtor_ = false; + } + } protected: - inline uint32_t Shard(uint32_t hash) { return hash & shard_mask_; } + inline void ForEachShard(const std::function& fn) { + uint32_t num_shards = GetNumShards(); + for (uint32_t i = 0; i < num_shards; i++) { + fn(shards_ + i); + } + } + + inline size_t SumOverShards( + const std::function& fn) const { + uint32_t num_shards = GetNumShards(); + size_t result = 0; + for (uint32_t i = 0; i < num_shards; i++) { + result += fn(shards_[i]); + } + return result; + } + + inline size_t SumOverShards2(size_t (CacheShard::*fn)() const) const { + return SumOverShards([fn](CacheShard& cs) { return (cs.*fn)(); }); + } + + // Must be called exactly once by derived class constructor + void InitShards(const std::function& placement_new) { + ForEachShard(placement_new); + destroy_shards_in_dtor_ = true; + } + + void AppendPrintableOptions(std::string& str) const override { + shards_[0].AppendPrintableOptions(str); + } private: - const uint32_t shard_mask_; - mutable port::Mutex capacity_mutex_; - size_t capacity_; - bool strict_capacity_limit_; - std::atomic last_id_; + CacheShard* const shards_; + bool destroy_shards_in_dtor_; }; // 512KB is traditional minimum shard size. diff --git a/options/options_test.cc b/options/options_test.cc index b89434c3a..37001379a 100644 --- a/options/options_test.cc +++ b/options/options_test.cc @@ -613,7 +613,7 @@ TEST_F(OptionsTest, GetColumnFamilyOptionsFromStringTest) { &new_cf_opt)); ASSERT_NE(new_cf_opt.blob_cache, nullptr); ASSERT_EQ(new_cf_opt.blob_cache->GetCapacity(), 1024UL * 1024UL); - ASSERT_EQ(static_cast(new_cf_opt.blob_cache.get()) + ASSERT_EQ(static_cast(new_cf_opt.blob_cache.get()) ->GetNumShardBits(), 4); ASSERT_EQ(new_cf_opt.blob_cache->HasStrictCapacityLimit(), true); @@ -1064,15 +1064,18 @@ TEST_F(OptionsTest, GetBlockBasedTableOptionsFromString) { &new_opt)); ASSERT_TRUE(new_opt.block_cache != nullptr); ASSERT_EQ(new_opt.block_cache->GetCapacity(), 1024UL*1024UL); - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache)->GetNumShardBits(), 4); + ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache) + ->GetNumShardBits(), + 4); ASSERT_EQ(new_opt.block_cache->HasStrictCapacityLimit(), true); ASSERT_EQ(std::dynamic_pointer_cast( new_opt.block_cache)->GetHighPriPoolRatio(), 0.5); ASSERT_TRUE(new_opt.block_cache_compressed != nullptr); ASSERT_EQ(new_opt.block_cache_compressed->GetCapacity(), 1024UL*1024UL); - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache_compressed)->GetNumShardBits(), 4); + ASSERT_EQ(std::dynamic_pointer_cast( + new_opt.block_cache_compressed) + ->GetNumShardBits(), + 4); ASSERT_EQ(new_opt.block_cache_compressed->HasStrictCapacityLimit(), true); ASSERT_EQ(std::dynamic_pointer_cast( new_opt.block_cache_compressed)->GetHighPriPoolRatio(), @@ -1088,9 +1091,9 @@ TEST_F(OptionsTest, GetBlockBasedTableOptionsFromString) { ASSERT_TRUE(new_opt.block_cache != nullptr); ASSERT_EQ(new_opt.block_cache->GetCapacity(), 2*1024UL*1024UL); // Default values - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache)->GetNumShardBits(), - GetDefaultCacheShardBits(new_opt.block_cache->GetCapacity())); + ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache) + ->GetNumShardBits(), + GetDefaultCacheShardBits(new_opt.block_cache->GetCapacity())); ASSERT_EQ(new_opt.block_cache->HasStrictCapacityLimit(), false); ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache) ->GetHighPriPoolRatio(), @@ -1098,10 +1101,11 @@ TEST_F(OptionsTest, GetBlockBasedTableOptionsFromString) { ASSERT_TRUE(new_opt.block_cache_compressed != nullptr); ASSERT_EQ(new_opt.block_cache_compressed->GetCapacity(), 2*1024UL*1024UL); // Default values - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache_compressed)->GetNumShardBits(), - GetDefaultCacheShardBits( - new_opt.block_cache_compressed->GetCapacity())); + ASSERT_EQ( + std::dynamic_pointer_cast( + new_opt.block_cache_compressed) + ->GetNumShardBits(), + GetDefaultCacheShardBits(new_opt.block_cache_compressed->GetCapacity())); ASSERT_EQ(new_opt.block_cache_compressed->HasStrictCapacityLimit(), false); ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache_compressed) ->GetHighPriPoolRatio(), @@ -1115,15 +1119,18 @@ TEST_F(OptionsTest, GetBlockBasedTableOptionsFromString) { "high_pri_pool_ratio=0.0;}", &new_opt)); ASSERT_EQ(new_opt.block_cache->GetCapacity(), 0); - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache)->GetNumShardBits(), 5); + ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache) + ->GetNumShardBits(), + 5); ASSERT_EQ(new_opt.block_cache->HasStrictCapacityLimit(), false); ASSERT_EQ(std::dynamic_pointer_cast( new_opt.block_cache)->GetHighPriPoolRatio(), 0.5); ASSERT_TRUE(new_opt.block_cache_compressed != nullptr); ASSERT_EQ(new_opt.block_cache_compressed->GetCapacity(), 0); - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache_compressed)->GetNumShardBits(), 5); + ASSERT_EQ(std::dynamic_pointer_cast( + new_opt.block_cache_compressed) + ->GetNumShardBits(), + 5); ASSERT_EQ(new_opt.block_cache_compressed->HasStrictCapacityLimit(), false); ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache_compressed) ->GetHighPriPoolRatio(), @@ -1139,16 +1146,19 @@ TEST_F(OptionsTest, GetBlockBasedTableOptionsFromString) { &new_opt)); ASSERT_TRUE(new_opt.block_cache != nullptr); ASSERT_EQ(new_opt.block_cache->GetCapacity(), 1024UL*1024UL); - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache)->GetNumShardBits(), 4); + ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache) + ->GetNumShardBits(), + 4); ASSERT_EQ(new_opt.block_cache->HasStrictCapacityLimit(), true); ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache) ->GetHighPriPoolRatio(), 0.5); ASSERT_TRUE(new_opt.block_cache_compressed != nullptr); ASSERT_EQ(new_opt.block_cache_compressed->GetCapacity(), 1024UL*1024UL); - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache_compressed)->GetNumShardBits(), 4); + ASSERT_EQ(std::dynamic_pointer_cast( + new_opt.block_cache_compressed) + ->GetNumShardBits(), + 4); ASSERT_EQ(new_opt.block_cache_compressed->HasStrictCapacityLimit(), true); ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache_compressed) ->GetHighPriPoolRatio(), @@ -2790,7 +2800,7 @@ TEST_F(OptionsOldApiTest, GetColumnFamilyOptionsFromStringTest) { &new_cf_opt)); ASSERT_NE(new_cf_opt.blob_cache, nullptr); ASSERT_EQ(new_cf_opt.blob_cache->GetCapacity(), 1024UL * 1024UL); - ASSERT_EQ(static_cast(new_cf_opt.blob_cache.get()) + ASSERT_EQ(static_cast(new_cf_opt.blob_cache.get()) ->GetNumShardBits(), 4); ASSERT_EQ(new_cf_opt.blob_cache->HasStrictCapacityLimit(), true); @@ -2970,15 +2980,18 @@ TEST_F(OptionsOldApiTest, GetBlockBasedTableOptionsFromString) { &new_opt)); ASSERT_TRUE(new_opt.block_cache != nullptr); ASSERT_EQ(new_opt.block_cache->GetCapacity(), 1024UL*1024UL); - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache)->GetNumShardBits(), 4); + ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache) + ->GetNumShardBits(), + 4); ASSERT_EQ(new_opt.block_cache->HasStrictCapacityLimit(), true); ASSERT_EQ(std::dynamic_pointer_cast( new_opt.block_cache)->GetHighPriPoolRatio(), 0.5); ASSERT_TRUE(new_opt.block_cache_compressed != nullptr); ASSERT_EQ(new_opt.block_cache_compressed->GetCapacity(), 1024UL*1024UL); - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache_compressed)->GetNumShardBits(), 4); + ASSERT_EQ(std::dynamic_pointer_cast( + new_opt.block_cache_compressed) + ->GetNumShardBits(), + 4); ASSERT_EQ(new_opt.block_cache_compressed->HasStrictCapacityLimit(), true); ASSERT_EQ(std::dynamic_pointer_cast( new_opt.block_cache_compressed)->GetHighPriPoolRatio(), @@ -2993,9 +3006,9 @@ TEST_F(OptionsOldApiTest, GetBlockBasedTableOptionsFromString) { ASSERT_TRUE(new_opt.block_cache != nullptr); ASSERT_EQ(new_opt.block_cache->GetCapacity(), 2*1024UL*1024UL); // Default values - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache)->GetNumShardBits(), - GetDefaultCacheShardBits(new_opt.block_cache->GetCapacity())); + ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache) + ->GetNumShardBits(), + GetDefaultCacheShardBits(new_opt.block_cache->GetCapacity())); ASSERT_EQ(new_opt.block_cache->HasStrictCapacityLimit(), false); ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache) ->GetHighPriPoolRatio(), @@ -3003,10 +3016,11 @@ TEST_F(OptionsOldApiTest, GetBlockBasedTableOptionsFromString) { ASSERT_TRUE(new_opt.block_cache_compressed != nullptr); ASSERT_EQ(new_opt.block_cache_compressed->GetCapacity(), 2*1024UL*1024UL); // Default values - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache_compressed)->GetNumShardBits(), - GetDefaultCacheShardBits( - new_opt.block_cache_compressed->GetCapacity())); + ASSERT_EQ( + std::dynamic_pointer_cast( + new_opt.block_cache_compressed) + ->GetNumShardBits(), + GetDefaultCacheShardBits(new_opt.block_cache_compressed->GetCapacity())); ASSERT_EQ(new_opt.block_cache_compressed->HasStrictCapacityLimit(), false); ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache_compressed) ->GetHighPriPoolRatio(), @@ -3020,15 +3034,18 @@ TEST_F(OptionsOldApiTest, GetBlockBasedTableOptionsFromString) { "high_pri_pool_ratio=0.0;}", &new_opt)); ASSERT_EQ(new_opt.block_cache->GetCapacity(), 0); - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache)->GetNumShardBits(), 5); + ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache) + ->GetNumShardBits(), + 5); ASSERT_EQ(new_opt.block_cache->HasStrictCapacityLimit(), false); ASSERT_EQ(std::dynamic_pointer_cast( new_opt.block_cache)->GetHighPriPoolRatio(), 0.5); ASSERT_TRUE(new_opt.block_cache_compressed != nullptr); ASSERT_EQ(new_opt.block_cache_compressed->GetCapacity(), 0); - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache_compressed)->GetNumShardBits(), 5); + ASSERT_EQ(std::dynamic_pointer_cast( + new_opt.block_cache_compressed) + ->GetNumShardBits(), + 5); ASSERT_EQ(new_opt.block_cache_compressed->HasStrictCapacityLimit(), false); ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache_compressed) ->GetHighPriPoolRatio(), @@ -3043,16 +3060,19 @@ TEST_F(OptionsOldApiTest, GetBlockBasedTableOptionsFromString) { &new_opt)); ASSERT_TRUE(new_opt.block_cache != nullptr); ASSERT_EQ(new_opt.block_cache->GetCapacity(), 1024UL*1024UL); - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache)->GetNumShardBits(), 4); + ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache) + ->GetNumShardBits(), + 4); ASSERT_EQ(new_opt.block_cache->HasStrictCapacityLimit(), true); ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache) ->GetHighPriPoolRatio(), 0.5); ASSERT_TRUE(new_opt.block_cache_compressed != nullptr); ASSERT_EQ(new_opt.block_cache_compressed->GetCapacity(), 1024UL*1024UL); - ASSERT_EQ(std::dynamic_pointer_cast( - new_opt.block_cache_compressed)->GetNumShardBits(), 4); + ASSERT_EQ(std::dynamic_pointer_cast( + new_opt.block_cache_compressed) + ->GetNumShardBits(), + 4); ASSERT_EQ(new_opt.block_cache_compressed->HasStrictCapacityLimit(), true); ASSERT_EQ(std::dynamic_pointer_cast(new_opt.block_cache_compressed) ->GetHighPriPoolRatio(), diff --git a/port/win/port_win.h b/port/win/port_win.h index 5a8f66051..9ac8d045d 100644 --- a/port/win/port_win.h +++ b/port/win/port_win.h @@ -246,13 +246,8 @@ inline void cacheline_aligned_free(void *memblock) { extern const size_t kPageSize; -// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52991 for MINGW32 -// could not be worked around with by -mno-ms-bitfields -#ifndef __MINGW32__ -#define ALIGN_AS(n) __declspec(align(n)) -#else -#define ALIGN_AS(n) -#endif +// Part of C++11 +#define ALIGN_AS(n) alignas(n) static inline void AsmVolatilePause() { #if defined(_M_IX86) || defined(_M_X64) || defined(_M_ARM64) || defined(_M_ARM) diff --git a/table/block_based/block_based_table_factory.cc b/table/block_based/block_based_table_factory.cc index 1a11096cf..53b59e3d8 100644 --- a/table/block_based/block_based_table_factory.cc +++ b/table/block_based/block_based_table_factory.cc @@ -524,32 +524,32 @@ Status CheckCacheOptionCompatibility(const BlockBasedTableOptions& bbto) { // More complex test of shared key space, in case the instances are wrappers // for some shared underlying cache. - std::string sentinel_key(size_t{1}, '\0'); + CacheKey sentinel_key = CacheKey::CreateUniqueForProcessLifetime(); static char kRegularBlockCacheMarker = 'b'; static char kCompressedBlockCacheMarker = 'c'; static char kPersistentCacheMarker = 'p'; if (bbto.block_cache) { bbto.block_cache - ->Insert(Slice(sentinel_key), &kRegularBlockCacheMarker, 1, + ->Insert(sentinel_key.AsSlice(), &kRegularBlockCacheMarker, 1, GetNoopDeleterForRole()) .PermitUncheckedError(); } if (bbto.block_cache_compressed) { bbto.block_cache_compressed - ->Insert(Slice(sentinel_key), &kCompressedBlockCacheMarker, 1, + ->Insert(sentinel_key.AsSlice(), &kCompressedBlockCacheMarker, 1, GetNoopDeleterForRole()) .PermitUncheckedError(); } if (bbto.persistent_cache) { // Note: persistent cache copies the data, not keeping the pointer bbto.persistent_cache - ->Insert(Slice(sentinel_key), &kPersistentCacheMarker, 1) + ->Insert(sentinel_key.AsSlice(), &kPersistentCacheMarker, 1) .PermitUncheckedError(); } // If we get something different from what we inserted, that indicates // dangerously overlapping key spaces. if (bbto.block_cache) { - auto handle = bbto.block_cache->Lookup(Slice(sentinel_key)); + auto handle = bbto.block_cache->Lookup(sentinel_key.AsSlice()); if (handle) { auto v = static_cast(bbto.block_cache->Value(handle)); char c = *v; @@ -568,7 +568,7 @@ Status CheckCacheOptionCompatibility(const BlockBasedTableOptions& bbto) { } } if (bbto.block_cache_compressed) { - auto handle = bbto.block_cache_compressed->Lookup(Slice(sentinel_key)); + auto handle = bbto.block_cache_compressed->Lookup(sentinel_key.AsSlice()); if (handle) { auto v = static_cast(bbto.block_cache_compressed->Value(handle)); char c = *v; @@ -591,7 +591,7 @@ Status CheckCacheOptionCompatibility(const BlockBasedTableOptions& bbto) { if (bbto.persistent_cache) { std::unique_ptr data; size_t size = 0; - bbto.persistent_cache->Lookup(Slice(sentinel_key), &data, &size) + bbto.persistent_cache->Lookup(sentinel_key.AsSlice(), &data, &size) .PermitUncheckedError(); if (data && size > 0) { if (data[0] == kRegularBlockCacheMarker) { diff --git a/table/block_based/block_based_table_reader.cc b/table/block_based/block_based_table_reader.cc index 40dcd6e1f..b331cb4e5 100644 --- a/table/block_based/block_based_table_reader.cc +++ b/table/block_based/block_based_table_reader.cc @@ -21,7 +21,6 @@ #include "cache/cache_entry_roles.h" #include "cache/cache_key.h" -#include "cache/sharded_cache.h" #include "db/compaction/compaction_picker.h" #include "db/dbformat.h" #include "db/pinned_iterators_manager.h"