Refactor WriteBufferManager::CacheRep into CacheReservationManager (#8506)
Summary: Context: To help cap various memory usage by a single limit of the block cache capacity, we charge the memory usage through inserting/releasing dummy entries in the block cache. CacheReservationManager is such a class (non thread-safe) responsible for inserting/removing dummy entries to reserve cache space for memory used by the class user. - Refactored the inner private class CacheRep of WriteBufferManager into public CacheReservationManager class for reusability such as for https://github.com/facebook/rocksdb/pull/8428 - Encapsulated implementation details of cache key generation and dummy entries insertion/release in cache reservation as discussed in https://github.com/facebook/rocksdb/pull/8506#discussion_r666550838 - Consolidated increase/decrease cache reservation into one API - UpdateCacheReservation. - Adjusted the previous dummy entry release algorithm in decreasing cache reservation to be loop-releasing dummy entries to stay symmetric to dummy entry insertion algorithm - Made the previous dummy entry release algorithm in delayed decrease mode more aggressive for better decreasing cache reservation when memory used is less likely to increase back. Previously, the algorithms only release 1 dummy entries when new_mem_used < 3/4 * cache_allocated_size_ and cache_allocated_size_ - kSizeDummyEntry > new_mem_used. Now, the algorithms loop-releases as many dummy entries as possible when new_mem_used < 3/4 * cache_allocated_size_. - Updated WriteBufferManager's test cases to adapt to changes on the release algorithm mentioned above and left comment for some test cases for clarity - Replaced the previous cache key prefix generation (utilizing object address related to the cache client) with one that utilizes Cache->NewID() to prevent cache-key collision among dummy entry clients sharing the same cache. The specific collision we are preventing happens when the object address is reused for a new cache-key prefix while the old cache-key using that same object address in its prefix still exists in the cache. This could happen due to that, under LRU cache policy, there is a possible delay in releasing a cache entry after the cache client object owning that cache entry get deallocated. In this case, the object address related to the cache client object can get reused for other client object to generate a new cache-key prefix. This prefix generation can be made obsolete after Peter's unification of all the code generating cache key, mentioned in https://github.com/facebook/rocksdb/pull/8506#discussion_r667265255 Pull Request resolved: https://github.com/facebook/rocksdb/pull/8506 Test Plan: - Passing the added unit tests cache_reservation_manager_test.cc - Passing existing and adjusted write_buffer_manager_test.cc Reviewed By: ajkr Differential Revision: D29644135 Pulled By: hx235 fbshipit-source-id: 0fc93fbfe4a40bb41be85c314f8f2bafa8b741f7main
Hui Xiao
3 years ago
committed by
Facebook GitHub Bot
parent
c521f22a1e
commit
74cfe7db60
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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
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// This source code is licensed under both the GPLv2 (found in the
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// COPYING file in the root directory) and Apache 2.0 License
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// (found in the LICENSE.Apache file in the root directory).
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//
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// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file. See the AUTHORS file for names of contributors.
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#include "cache/cache_reservation_manager.h" |
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#include <cassert> |
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#include <cstddef> |
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#include <cstring> |
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#include <memory> |
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#include "cache/cache_entry_roles.h" |
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#include "rocksdb/cache.h" |
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#include "rocksdb/slice.h" |
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#include "rocksdb/status.h" |
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#include "table/block_based/block_based_table_reader.h" |
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#include "util/coding.h" |
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namespace ROCKSDB_NAMESPACE { |
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CacheReservationManager::CacheReservationManager(std::shared_ptr<Cache> cache, |
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bool delayed_decrease) |
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: delayed_decrease_(delayed_decrease), cache_allocated_size_(0) { |
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assert(cache != nullptr); |
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cache_ = cache; |
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std::memset(cache_key_, 0, kCacheKeyPrefixSize + kMaxVarint64Length); |
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EncodeVarint64(cache_key_, cache_->NewId()); |
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} |
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CacheReservationManager::~CacheReservationManager() { |
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for (auto* handle : dummy_handles_) { |
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cache_->Release(handle, true); |
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} |
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} |
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template <CacheEntryRole R> |
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Status CacheReservationManager::UpdateCacheReservation( |
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std::size_t new_mem_used) { |
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std::size_t cur_cache_allocated_size = |
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cache_allocated_size_.load(std::memory_order_relaxed); |
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if (new_mem_used == cur_cache_allocated_size) { |
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return Status::OK(); |
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} else if (new_mem_used > cur_cache_allocated_size) { |
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Status s = IncreaseCacheReservation<R>(new_mem_used); |
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return s; |
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} else { |
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// In delayed decrease mode, we don't decrease cache reservation
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// untill the memory usage is less than 3/4 of what we reserve
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// in the cache.
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// We do this because
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// (1) Dummy entry insertion is expensive in block cache
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// (2) Delayed releasing previously inserted dummy entries can save such
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// expensive dummy entry insertion on memory increase in the near future,
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// which is likely to happen when the memory usage is greater than or equal
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// to 3/4 of what we reserve
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if (delayed_decrease_ && new_mem_used >= cur_cache_allocated_size / 4 * 3) { |
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return Status::OK(); |
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} else { |
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Status s = DecreaseCacheReservation(new_mem_used); |
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return s; |
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} |
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} |
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} |
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// Explicitly instantiate templates for "CacheEntryRole" values we use.
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// This makes it possible to keep the template definitions in the .cc file.
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template Status CacheReservationManager::UpdateCacheReservation< |
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CacheEntryRole::kWriteBuffer>(std::size_t new_mem_used); |
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// For cache reservation manager unit tests
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template Status CacheReservationManager::UpdateCacheReservation< |
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CacheEntryRole::kMisc>(std::size_t new_mem_used); |
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template <CacheEntryRole R> |
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Status CacheReservationManager::IncreaseCacheReservation( |
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std::size_t new_mem_used) { |
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Status return_status = Status::OK(); |
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while (new_mem_used > cache_allocated_size_.load(std::memory_order_relaxed)) { |
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Cache::Handle* handle = nullptr; |
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return_status = cache_->Insert(GetNextCacheKey(), nullptr, kSizeDummyEntry, |
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GetNoopDeleterForRole<R>(), &handle); |
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if (return_status != Status::OK()) { |
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return return_status; |
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} |
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dummy_handles_.push_back(handle); |
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cache_allocated_size_ += kSizeDummyEntry; |
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} |
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return return_status; |
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} |
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Status CacheReservationManager::DecreaseCacheReservation( |
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std::size_t new_mem_used) { |
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Status return_status = Status::OK(); |
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// Decrease to the smallest multiple of kSizeDummyEntry that is greater than
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// or equal to new_mem_used We do addition instead of new_mem_used <=
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// cache_allocated_size_.load(std::memory_order_relaxed) - kSizeDummyEntry to
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// avoid underflow of size_t when cache_allocated_size_ = 0
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while (new_mem_used + kSizeDummyEntry <= |
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cache_allocated_size_.load(std::memory_order_relaxed)) { |
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assert(!dummy_handles_.empty()); |
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auto* handle = dummy_handles_.back(); |
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cache_->Release(handle, true); |
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dummy_handles_.pop_back(); |
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cache_allocated_size_ -= kSizeDummyEntry; |
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} |
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return return_status; |
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} |
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std::size_t CacheReservationManager::GetTotalReservedCacheSize() { |
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return cache_allocated_size_.load(std::memory_order_relaxed); |
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} |
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Slice CacheReservationManager::GetNextCacheKey() { |
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// Calling this function will have the side-effect of changing the
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// underlying cache_key_ that is shared among other keys generated from this
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// fucntion. Therefore please make sure the previous keys are saved/copied
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// before calling this function.
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std::memset(cache_key_ + kCacheKeyPrefixSize, 0, kMaxVarint64Length); |
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char* end = |
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EncodeVarint64(cache_key_ + kCacheKeyPrefixSize, next_cache_key_id_++); |
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return Slice(cache_key_, static_cast<std::size_t>(end - cache_key_)); |
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} |
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} // namespace ROCKSDB_NAMESPACE
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@ -0,0 +1,97 @@ |
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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
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// This source code is licensed under both the GPLv2 (found in the
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// COPYING file in the root directory) and Apache 2.0 License
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// (found in the LICENSE.Apache file in the root directory).
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//
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// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file. See the AUTHORS file for names of contributors.
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#pragma once |
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#include <atomic> |
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#include <cstddef> |
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#include <cstdint> |
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#include <memory> |
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#include <vector> |
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#include "cache/cache_entry_roles.h" |
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#include "rocksdb/cache.h" |
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#include "rocksdb/slice.h" |
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#include "rocksdb/status.h" |
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#include "table/block_based/block_based_table_reader.h" |
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#include "util/coding.h" |
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namespace ROCKSDB_NAMESPACE { |
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// CacheReservationManager is for reserving cache space for the memory used
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// through inserting/releasing dummy entries in the cache.
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// This class is not thread-safe.
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class CacheReservationManager { |
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public: |
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// Construct a CacheReservationManager
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// @param cache The cache where dummy entries are inserted and released for
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// reserving cache space
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// @param delayed_decrease If set true, then dummy entries won't be released
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// immediately when memory usage decreases.
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// Instead, it will be released when the memory usage
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// decreases to 3/4 of what we have reserved so far.
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// This is for saving some future dummy entry
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// insertion when memory usage increases are likely to
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// happen in the near future.
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explicit CacheReservationManager(std::shared_ptr<Cache> cache, |
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bool delayed_decrease = false); |
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// no copy constructor, copy assignment, move constructor, move assignment
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CacheReservationManager(const CacheReservationManager &) = delete; |
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CacheReservationManager &operator=(const CacheReservationManager &) = delete; |
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CacheReservationManager(CacheReservationManager &&) = delete; |
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CacheReservationManager &operator=(CacheReservationManager &&) = delete; |
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~CacheReservationManager(); |
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template <CacheEntryRole R> |
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// Insert and release dummy entries in the cache to
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// match the size of total dummy entries with the smallest multiple of
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// kSizeDummyEntry that is greater than or equal to new_mem_used
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//
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// Insert dummy entries if new_memory_used > cache_allocated_size_;
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//
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// Release dummy entries if new_memory_used < cache_allocated_size_
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// (and new_memory_used < cache_allocated_size_ * 3/4
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// when delayed_decrease is set true);
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//
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// Keey dummy entries the same if (1) new_memory_used == cache_allocated_size_
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// or (2) new_memory_used is in the interval of
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// [cache_allocated_size_ * 3/4, cache_allocated_size) when delayed_decrease
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// is set true.
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//
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// On inserting dummy entries, it returns Status::OK() if all dummy entry
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// insertions succeed. Otherwise, it returns the first non-ok status;
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// On releasing dummy entries, it always returns Status::OK().
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// On keeping dummy entries the same, it always returns Status::OK().
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Status UpdateCacheReservation(std::size_t new_memory_used); |
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std::size_t GetTotalReservedCacheSize(); |
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private: |
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static constexpr std::size_t kSizeDummyEntry = 256 * 1024; |
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// The key will be longer than keys for blocks in SST files so they won't
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// conflict.
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static const std::size_t kCacheKeyPrefixSize = |
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BlockBasedTable::kMaxCacheKeyPrefixSize + kMaxVarint64Length; |
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Slice GetNextCacheKey(); |
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template <CacheEntryRole R> |
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Status IncreaseCacheReservation(std::size_t new_mem_used); |
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Status DecreaseCacheReservation(std::size_t new_mem_used); |
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std::shared_ptr<Cache> cache_; |
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bool delayed_decrease_; |
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std::atomic<std::size_t> cache_allocated_size_; |
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std::vector<Cache::Handle *> dummy_handles_; |
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std::uint64_t next_cache_key_id_ = 0; |
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// The non-prefix part will be updated according to the ID to use.
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char cache_key_[kCacheKeyPrefixSize + kMaxVarint64Length]; |
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}; |
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} // namespace ROCKSDB_NAMESPACE
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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
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// This source code is licensed under both the GPLv2 (found in the
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// COPYING file in the root directory) and Apache 2.0 License
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// (found in the LICENSE.Apache file in the root directory).
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//
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// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file. See the AUTHORS file for names of contributors.
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#include "cache/cache_reservation_manager.h" |
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#include <cstddef> |
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#include <cstring> |
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#include <memory> |
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#include "cache/cache_entry_roles.h" |
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#include "rocksdb/cache.h" |
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#include "rocksdb/slice.h" |
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#include "table/block_based/block_based_table_reader.h" |
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#include "test_util/testharness.h" |
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#include "util/coding.h" |
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namespace ROCKSDB_NAMESPACE { |
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class CacheReservationManagerTest : public ::testing::Test { |
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protected: |
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static constexpr std::size_t kOneGigabyte = 1024 * 1024 * 1024; |
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static constexpr int kNumShardBits = 0; // 2^0 shard
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static constexpr std::size_t kSizeDummyEntry = 256 * 1024; |
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static const std::size_t kCacheKeyPrefixSize = |
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BlockBasedTable::kMaxCacheKeyPrefixSize + kMaxVarint64Length; |
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static constexpr std::size_t kMetaDataChargeOverhead = 10000; |
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std::shared_ptr<Cache> cache = NewLRUCache(kOneGigabyte, kNumShardBits); |
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std::unique_ptr<CacheReservationManager> test_cache_rev_mng; |
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CacheReservationManagerTest() { |
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test_cache_rev_mng.reset(new CacheReservationManager(cache)); |
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} |
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}; |
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TEST_F(CacheReservationManagerTest, GenerateCacheKey) { |
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// The first cache reservation manager owning the cache will have
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// cache->NewId() = 1
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constexpr std::size_t kCacheNewId = 1; |
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// The first key generated inside of cache reservation manager will have
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// next_cache_key_id = 0
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constexpr std::size_t kCacheKeyId = 0; |
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char expected_cache_key[kCacheKeyPrefixSize + kMaxVarint64Length]; |
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std::memset(expected_cache_key, 0, kCacheKeyPrefixSize + kMaxVarint64Length); |
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EncodeVarint64(expected_cache_key, kCacheNewId); |
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char* end = |
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EncodeVarint64(expected_cache_key + kCacheKeyPrefixSize, kCacheKeyId); |
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Slice expected_cache_key_slice( |
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expected_cache_key, static_cast<std::size_t>(end - expected_cache_key)); |
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std::size_t new_mem_used = 1 * kSizeDummyEntry; |
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Status s = |
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test_cache_rev_mng |
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->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
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new_mem_used); |
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ASSERT_EQ(s, Status::OK()); |
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ASSERT_GE(cache->GetPinnedUsage(), 1 * kSizeDummyEntry); |
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ASSERT_LT(cache->GetPinnedUsage(), |
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1 * kSizeDummyEntry + kMetaDataChargeOverhead); |
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Cache::Handle* handle = cache->Lookup(expected_cache_key_slice); |
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EXPECT_NE(handle, nullptr) |
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<< "Failed to generate the cache key for the dummy entry correctly"; |
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// Clean up the returned handle from Lookup() to prevent memory leak
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cache->Release(handle); |
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} |
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TEST_F(CacheReservationManagerTest, KeepCacheReservationTheSame) { |
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std::size_t new_mem_used = 1 * kSizeDummyEntry; |
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Status s = |
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test_cache_rev_mng |
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->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
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new_mem_used); |
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ASSERT_EQ(s, Status::OK()); |
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ASSERT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
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1 * kSizeDummyEntry); |
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std::size_t initial_pinned_usage = cache->GetPinnedUsage(); |
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ASSERT_GE(initial_pinned_usage, 1 * kSizeDummyEntry); |
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ASSERT_LT(initial_pinned_usage, |
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1 * kSizeDummyEntry + kMetaDataChargeOverhead); |
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s = test_cache_rev_mng |
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->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
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new_mem_used); |
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EXPECT_EQ(s, Status::OK()) |
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<< "Failed to keep cache reservation the same when new_mem_used equals " |
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"to current cache reservation"; |
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EXPECT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
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1 * kSizeDummyEntry) |
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<< "Failed to bookkeep correctly when new_mem_used equals to current " |
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"cache reservation"; |
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EXPECT_EQ(cache->GetPinnedUsage(), initial_pinned_usage) |
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<< "Failed to keep underlying dummy entries the same when new_mem_used " |
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"equals to current cache reservation"; |
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} |
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TEST_F(CacheReservationManagerTest, |
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IncreaseCacheReservationByMultiplesOfDummyEntrySize) { |
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std::size_t new_mem_used = 2 * kSizeDummyEntry; |
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Status s = |
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test_cache_rev_mng |
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->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
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new_mem_used); |
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|
EXPECT_EQ(s, Status::OK()) |
||||||
|
<< "Failed to increase cache reservation correctly"; |
||||||
|
EXPECT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
2 * kSizeDummyEntry) |
||||||
|
<< "Failed to bookkeep cache reservation increase correctly"; |
||||||
|
EXPECT_GE(cache->GetPinnedUsage(), 2 * kSizeDummyEntry) |
||||||
|
<< "Failed to increase underlying dummy entries in cache correctly"; |
||||||
|
EXPECT_LT(cache->GetPinnedUsage(), |
||||||
|
2 * kSizeDummyEntry + kMetaDataChargeOverhead) |
||||||
|
<< "Failed to increase underlying dummy entries in cache correctly"; |
||||||
|
} |
||||||
|
|
||||||
|
TEST_F(CacheReservationManagerTest, |
||||||
|
IncreaseCacheReservationNotByMultiplesOfDummyEntrySize) { |
||||||
|
std::size_t new_mem_used = 2 * kSizeDummyEntry + kSizeDummyEntry / 2; |
||||||
|
Status s = |
||||||
|
test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
EXPECT_EQ(s, Status::OK()) |
||||||
|
<< "Failed to increase cache reservation correctly"; |
||||||
|
EXPECT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
3 * kSizeDummyEntry) |
||||||
|
<< "Failed to bookkeep cache reservation increase correctly"; |
||||||
|
EXPECT_GE(cache->GetPinnedUsage(), 3 * kSizeDummyEntry) |
||||||
|
<< "Failed to increase underlying dummy entries in cache correctly"; |
||||||
|
EXPECT_LT(cache->GetPinnedUsage(), |
||||||
|
3 * kSizeDummyEntry + kMetaDataChargeOverhead) |
||||||
|
<< "Failed to increase underlying dummy entries in cache correctly"; |
||||||
|
} |
||||||
|
|
||||||
|
TEST(CacheReservationManagerIncreaseReservcationOnFullCacheTest, |
||||||
|
IncreaseCacheReservationOnFullCache) { |
||||||
|
constexpr std::size_t kOneMegabyte = 1024 * 1024; |
||||||
|
constexpr std::size_t kOneGigabyte = 1024 * 1024 * 1024; |
||||||
|
constexpr std::size_t kSizeDummyEntry = 256 * 1024; |
||||||
|
constexpr std::size_t kMetaDataChargeOverhead = 10000; |
||||||
|
|
||||||
|
LRUCacheOptions lo; |
||||||
|
lo.capacity = kOneMegabyte; |
||||||
|
lo.num_shard_bits = 0; // 2^0 shard
|
||||||
|
lo.strict_capacity_limit = true; |
||||||
|
std::shared_ptr<Cache> cache = NewLRUCache(lo); |
||||||
|
std::unique_ptr<CacheReservationManager> test_cache_rev_mng( |
||||||
|
new CacheReservationManager(cache)); |
||||||
|
|
||||||
|
std::size_t new_mem_used = kOneMegabyte + 1; |
||||||
|
Status s = |
||||||
|
test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
EXPECT_EQ(s, Status::Incomplete()) |
||||||
|
<< "Failed to return status to indicate failure of dummy entry insertion " |
||||||
|
"during cache reservation on full cache"; |
||||||
|
EXPECT_GE(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
1 * kSizeDummyEntry) |
||||||
|
<< "Failed to bookkeep correctly before cache resevation failure happens " |
||||||
|
"due to full cache"; |
||||||
|
EXPECT_LE(test_cache_rev_mng->GetTotalReservedCacheSize(), kOneMegabyte) |
||||||
|
<< "Failed to bookkeep correctly (i.e, bookkeep only successful dummy " |
||||||
|
"entry insertions) when encountering cache resevation failure due to " |
||||||
|
"full cache"; |
||||||
|
EXPECT_GE(cache->GetPinnedUsage(), 1 * kSizeDummyEntry) |
||||||
|
<< "Failed to insert underlying dummy entries correctly when " |
||||||
|
"encountering cache resevation failure due to full cache"; |
||||||
|
EXPECT_LE(cache->GetPinnedUsage(), kOneMegabyte) |
||||||
|
<< "Failed to insert underlying dummy entries correctly when " |
||||||
|
"encountering cache resevation failure due to full cache"; |
||||||
|
|
||||||
|
new_mem_used = kOneMegabyte / 2; // 2 dummy entries
|
||||||
|
s = test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
EXPECT_EQ(s, Status::OK()) |
||||||
|
<< "Failed to decrease cache reservation after encountering cache " |
||||||
|
"reservation failure due to full cache"; |
||||||
|
EXPECT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
2 * kSizeDummyEntry) |
||||||
|
<< "Failed to bookkeep cache reservation decrease correctly after " |
||||||
|
"encountering cache reservation due to full cache"; |
||||||
|
EXPECT_GE(cache->GetPinnedUsage(), 2 * kSizeDummyEntry) |
||||||
|
<< "Failed to release underlying dummy entries correctly on cache " |
||||||
|
"reservation decrease after encountering cache resevation failure due " |
||||||
|
"to full cache"; |
||||||
|
EXPECT_LT(cache->GetPinnedUsage(), |
||||||
|
2 * kSizeDummyEntry + kMetaDataChargeOverhead) |
||||||
|
<< "Failed to release underlying dummy entries correctly on cache " |
||||||
|
"reservation decrease after encountering cache resevation failure due " |
||||||
|
"to full cache"; |
||||||
|
|
||||||
|
// Create cache full again for subsequent tests
|
||||||
|
new_mem_used = kOneMegabyte + 1; |
||||||
|
s = test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
EXPECT_EQ(s, Status::Incomplete()) |
||||||
|
<< "Failed to return status to indicate failure of dummy entry insertion " |
||||||
|
"during cache reservation on full cache"; |
||||||
|
EXPECT_GE(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
1 * kSizeDummyEntry) |
||||||
|
<< "Failed to bookkeep correctly before cache resevation failure happens " |
||||||
|
"due to full cache"; |
||||||
|
EXPECT_LE(test_cache_rev_mng->GetTotalReservedCacheSize(), kOneMegabyte) |
||||||
|
<< "Failed to bookkeep correctly (i.e, bookkeep only successful dummy " |
||||||
|
"entry insertions) when encountering cache resevation failure due to " |
||||||
|
"full cache"; |
||||||
|
EXPECT_GE(cache->GetPinnedUsage(), 1 * kSizeDummyEntry) |
||||||
|
<< "Failed to insert underlying dummy entries correctly when " |
||||||
|
"encountering cache resevation failure due to full cache"; |
||||||
|
EXPECT_LE(cache->GetPinnedUsage(), kOneMegabyte) |
||||||
|
<< "Failed to insert underlying dummy entries correctly when " |
||||||
|
"encountering cache resevation failure due to full cache"; |
||||||
|
|
||||||
|
// Increase cache capacity so the previously failed insertion can fully
|
||||||
|
// succeed
|
||||||
|
cache->SetCapacity(kOneGigabyte); |
||||||
|
new_mem_used = kOneMegabyte + 1; |
||||||
|
s = test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
EXPECT_EQ(s, Status::OK()) |
||||||
|
<< "Failed to increase cache reservation after increasing cache capacity " |
||||||
|
"and mitigating cache full error"; |
||||||
|
EXPECT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
5 * kSizeDummyEntry) |
||||||
|
<< "Failed to bookkeep cache reservation increase correctly after " |
||||||
|
"increasing cache capacity and mitigating cache full error"; |
||||||
|
EXPECT_GE(cache->GetPinnedUsage(), 5 * kSizeDummyEntry) |
||||||
|
<< "Failed to insert underlying dummy entries correctly after increasing " |
||||||
|
"cache capacity and mitigating cache full error"; |
||||||
|
EXPECT_LT(cache->GetPinnedUsage(), |
||||||
|
5 * kSizeDummyEntry + kMetaDataChargeOverhead) |
||||||
|
<< "Failed to insert underlying dummy entries correctly after increasing " |
||||||
|
"cache capacity and mitigating cache full error"; |
||||||
|
} |
||||||
|
|
||||||
|
TEST_F(CacheReservationManagerTest, |
||||||
|
DecreaseCacheReservationByMultiplesOfDummyEntrySize) { |
||||||
|
std::size_t new_mem_used = 2 * kSizeDummyEntry; |
||||||
|
Status s = |
||||||
|
test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
ASSERT_EQ(s, Status::OK()); |
||||||
|
ASSERT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
2 * kSizeDummyEntry); |
||||||
|
ASSERT_GE(cache->GetPinnedUsage(), 2 * kSizeDummyEntry); |
||||||
|
ASSERT_LT(cache->GetPinnedUsage(), |
||||||
|
2 * kSizeDummyEntry + kMetaDataChargeOverhead); |
||||||
|
|
||||||
|
new_mem_used = 1 * kSizeDummyEntry; |
||||||
|
s = test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
EXPECT_EQ(s, Status::OK()) |
||||||
|
<< "Failed to decrease cache reservation correctly"; |
||||||
|
EXPECT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
1 * kSizeDummyEntry) |
||||||
|
<< "Failed to bookkeep cache reservation decrease correctly"; |
||||||
|
EXPECT_GE(cache->GetPinnedUsage(), 1 * kSizeDummyEntry) |
||||||
|
<< "Failed to decrease underlying dummy entries in cache correctly"; |
||||||
|
EXPECT_LT(cache->GetPinnedUsage(), |
||||||
|
1 * kSizeDummyEntry + kMetaDataChargeOverhead) |
||||||
|
<< "Failed to decrease underlying dummy entries in cache correctly"; |
||||||
|
} |
||||||
|
|
||||||
|
TEST_F(CacheReservationManagerTest, |
||||||
|
DecreaseCacheReservationNotByMultiplesOfDummyEntrySize) { |
||||||
|
std::size_t new_mem_used = 2 * kSizeDummyEntry; |
||||||
|
Status s = |
||||||
|
test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
ASSERT_EQ(s, Status::OK()); |
||||||
|
ASSERT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
2 * kSizeDummyEntry); |
||||||
|
ASSERT_GE(cache->GetPinnedUsage(), 2 * kSizeDummyEntry); |
||||||
|
ASSERT_LT(cache->GetPinnedUsage(), |
||||||
|
2 * kSizeDummyEntry + kMetaDataChargeOverhead); |
||||||
|
|
||||||
|
new_mem_used = kSizeDummyEntry / 2; |
||||||
|
s = test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
EXPECT_EQ(s, Status::OK()) |
||||||
|
<< "Failed to decrease cache reservation correctly"; |
||||||
|
EXPECT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
1 * kSizeDummyEntry) |
||||||
|
<< "Failed to bookkeep cache reservation decrease correctly"; |
||||||
|
EXPECT_GE(cache->GetPinnedUsage(), 1 * kSizeDummyEntry) |
||||||
|
<< "Failed to decrease underlying dummy entries in cache correctly"; |
||||||
|
EXPECT_LT(cache->GetPinnedUsage(), |
||||||
|
1 * kSizeDummyEntry + kMetaDataChargeOverhead) |
||||||
|
<< "Failed to decrease underlying dummy entries in cache correctly"; |
||||||
|
} |
||||||
|
|
||||||
|
TEST(CacheReservationManagerWithDelayedDecreaseTest, |
||||||
|
DecreaseCacheReservationWithDelayedDecrease) { |
||||||
|
constexpr std::size_t kOneGigabyte = 1024 * 1024 * 1024; |
||||||
|
constexpr std::size_t kSizeDummyEntry = 256 * 1024; |
||||||
|
constexpr std::size_t kMetaDataChargeOverhead = 10000; |
||||||
|
|
||||||
|
LRUCacheOptions lo; |
||||||
|
lo.capacity = kOneGigabyte; |
||||||
|
lo.num_shard_bits = 0; |
||||||
|
std::shared_ptr<Cache> cache = NewLRUCache(lo); |
||||||
|
std::unique_ptr<CacheReservationManager> test_cache_rev_mng( |
||||||
|
new CacheReservationManager(cache, true /* delayed_decrease */)); |
||||||
|
|
||||||
|
std::size_t new_mem_used = 8 * kSizeDummyEntry; |
||||||
|
Status s = |
||||||
|
test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
ASSERT_EQ(s, Status::OK()); |
||||||
|
ASSERT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
8 * kSizeDummyEntry); |
||||||
|
std::size_t initial_pinned_usage = cache->GetPinnedUsage(); |
||||||
|
ASSERT_GE(initial_pinned_usage, 8 * kSizeDummyEntry); |
||||||
|
ASSERT_LT(initial_pinned_usage, |
||||||
|
8 * kSizeDummyEntry + kMetaDataChargeOverhead); |
||||||
|
|
||||||
|
new_mem_used = 6 * kSizeDummyEntry; |
||||||
|
s = test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
EXPECT_EQ(s, Status::OK()) << "Failed to delay decreasing cache reservation"; |
||||||
|
EXPECT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
8 * kSizeDummyEntry) |
||||||
|
<< "Failed to bookkeep correctly when delaying cache reservation " |
||||||
|
"decrease"; |
||||||
|
EXPECT_EQ(cache->GetPinnedUsage(), initial_pinned_usage) |
||||||
|
<< "Failed to delay decreasing underlying dummy entries in cache"; |
||||||
|
|
||||||
|
new_mem_used = 7 * kSizeDummyEntry; |
||||||
|
s = test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
EXPECT_EQ(s, Status::OK()) << "Failed to delay decreasing cache reservation"; |
||||||
|
EXPECT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
8 * kSizeDummyEntry) |
||||||
|
<< "Failed to bookkeep correctly when delaying cache reservation " |
||||||
|
"decrease"; |
||||||
|
EXPECT_EQ(cache->GetPinnedUsage(), initial_pinned_usage) |
||||||
|
<< "Failed to delay decreasing underlying dummy entries in cache"; |
||||||
|
|
||||||
|
new_mem_used = 6 * kSizeDummyEntry - 1; |
||||||
|
s = test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
EXPECT_EQ(s, Status::OK()) |
||||||
|
<< "Failed to decrease cache reservation correctly when new_mem_used < " |
||||||
|
"GetTotalReservedCacheSize() * 3 / 4 on delayed decrease mode"; |
||||||
|
EXPECT_EQ(test_cache_rev_mng->GetTotalReservedCacheSize(), |
||||||
|
6 * kSizeDummyEntry) |
||||||
|
<< "Failed to bookkeep correctly when new_mem_used < " |
||||||
|
"GetTotalReservedCacheSize() * 3 / 4 on delayed decrease mode"; |
||||||
|
EXPECT_GE(cache->GetPinnedUsage(), 6 * kSizeDummyEntry) |
||||||
|
<< "Failed to decrease underlying dummy entries in cache when " |
||||||
|
"new_mem_used < GetTotalReservedCacheSize() * 3 / 4 on delayed " |
||||||
|
"decrease mode"; |
||||||
|
EXPECT_LT(cache->GetPinnedUsage(), |
||||||
|
6 * kSizeDummyEntry + kMetaDataChargeOverhead) |
||||||
|
<< "Failed to decrease underlying dummy entries in cache when " |
||||||
|
"new_mem_used < GetTotalReservedCacheSize() * 3 / 4 on delayed " |
||||||
|
"decrease mode"; |
||||||
|
} |
||||||
|
|
||||||
|
TEST(CacheReservationManagerDestructorTest, |
||||||
|
ReleaseRemainingDummyEntriesOnDestruction) { |
||||||
|
constexpr std::size_t kOneGigabyte = 1024 * 1024 * 1024; |
||||||
|
constexpr std::size_t kSizeDummyEntry = 256 * 1024; |
||||||
|
constexpr std::size_t kMetaDataChargeOverhead = 10000; |
||||||
|
|
||||||
|
LRUCacheOptions lo; |
||||||
|
lo.capacity = kOneGigabyte; |
||||||
|
lo.num_shard_bits = 0; |
||||||
|
std::shared_ptr<Cache> cache = NewLRUCache(lo); |
||||||
|
{ |
||||||
|
std::unique_ptr<CacheReservationManager> test_cache_rev_mng( |
||||||
|
new CacheReservationManager(cache)); |
||||||
|
std::size_t new_mem_used = 1 * kSizeDummyEntry; |
||||||
|
Status s = |
||||||
|
test_cache_rev_mng |
||||||
|
->UpdateCacheReservation<ROCKSDB_NAMESPACE::CacheEntryRole::kMisc>( |
||||||
|
new_mem_used); |
||||||
|
ASSERT_EQ(s, Status::OK()); |
||||||
|
ASSERT_GE(cache->GetPinnedUsage(), 1 * kSizeDummyEntry); |
||||||
|
ASSERT_LT(cache->GetPinnedUsage(), |
||||||
|
1 * kSizeDummyEntry + kMetaDataChargeOverhead); |
||||||
|
} |
||||||
|
EXPECT_EQ(cache->GetPinnedUsage(), 0 * kSizeDummyEntry) |
||||||
|
<< "Failed to release remaining underlying dummy entries in cache in " |
||||||
|
"CacheReservationManager's destructor"; |
||||||
|
} |
||||||
|
} // namespace ROCKSDB_NAMESPACE
|
||||||
|
|
||||||
|
int main(int argc, char** argv) { |
||||||
|
::testing::InitGoogleTest(&argc, argv); |
||||||
|
return RUN_ALL_TESTS(); |
||||||
|
} |
||||||
Loading…
Reference in new issue