You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
rocksdb/db/db_iterator_test.cc

1605 lines
48 KiB

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
//
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
#include "db/db_test_util.h"
#include "port/stack_trace.h"
#include "rocksdb/iostats_context.h"
#include "rocksdb/perf_context.h"
namespace rocksdb {
class DBIteratorTest : public DBTestBase {
public:
DBIteratorTest() : DBTestBase("/db_iterator_test") {}
};
TEST_F(DBIteratorTest, IteratorProperty) {
// The test needs to be changed if kPersistedTier is supported in iterator.
Options options = CurrentOptions();
CreateAndReopenWithCF({"pikachu"}, options);
Put(1, "1", "2");
ReadOptions ropt;
ropt.pin_data = false;
{
unique_ptr<Iterator> iter(db_->NewIterator(ropt, handles_[1]));
iter->SeekToFirst();
std::string prop_value;
ASSERT_NOK(iter->GetProperty("non_existing.value", &prop_value));
ASSERT_OK(iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("0", prop_value);
iter->Next();
ASSERT_OK(iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("Iterator is not valid.", prop_value);
}
Close();
}
TEST_F(DBIteratorTest, PersistedTierOnIterator) {
// The test needs to be changed if kPersistedTier is supported in iterator.
Options options = CurrentOptions();
CreateAndReopenWithCF({"pikachu"}, options);
ReadOptions ropt;
ropt.read_tier = kPersistedTier;
auto* iter = db_->NewIterator(ropt, handles_[1]);
ASSERT_TRUE(iter->status().IsNotSupported());
delete iter;
std::vector<Iterator*> iters;
ASSERT_TRUE(db_->NewIterators(ropt, {handles_[1]}, &iters).IsNotSupported());
Close();
}
TEST_F(DBIteratorTest, NonBlockingIteration) {
do {
ReadOptions non_blocking_opts, regular_opts;
Options options = CurrentOptions();
options.statistics = rocksdb::CreateDBStatistics();
non_blocking_opts.read_tier = kBlockCacheTier;
CreateAndReopenWithCF({"pikachu"}, options);
// write one kv to the database.
ASSERT_OK(Put(1, "a", "b"));
// scan using non-blocking iterator. We should find it because
// it is in memtable.
Iterator* iter = db_->NewIterator(non_blocking_opts, handles_[1]);
int count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
ASSERT_OK(iter->status());
count++;
}
ASSERT_EQ(count, 1);
delete iter;
// flush memtable to storage. Now, the key should not be in the
// memtable neither in the block cache.
ASSERT_OK(Flush(1));
// verify that a non-blocking iterator does not find any
// kvs. Neither does it do any IOs to storage.
uint64_t numopen = TestGetTickerCount(options, NO_FILE_OPENS);
uint64_t cache_added = TestGetTickerCount(options, BLOCK_CACHE_ADD);
iter = db_->NewIterator(non_blocking_opts, handles_[1]);
count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
count++;
}
ASSERT_EQ(count, 0);
ASSERT_TRUE(iter->status().IsIncomplete());
ASSERT_EQ(numopen, TestGetTickerCount(options, NO_FILE_OPENS));
ASSERT_EQ(cache_added, TestGetTickerCount(options, BLOCK_CACHE_ADD));
delete iter;
// read in the specified block via a regular get
ASSERT_EQ(Get(1, "a"), "b");
// verify that we can find it via a non-blocking scan
numopen = TestGetTickerCount(options, NO_FILE_OPENS);
cache_added = TestGetTickerCount(options, BLOCK_CACHE_ADD);
iter = db_->NewIterator(non_blocking_opts, handles_[1]);
count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
ASSERT_OK(iter->status());
count++;
}
ASSERT_EQ(count, 1);
ASSERT_EQ(numopen, TestGetTickerCount(options, NO_FILE_OPENS));
ASSERT_EQ(cache_added, TestGetTickerCount(options, BLOCK_CACHE_ADD));
delete iter;
// This test verifies block cache behaviors, which is not used by plain
// table format.
// Exclude kHashCuckoo as it does not support iteration currently
} while (ChangeOptions(kSkipPlainTable | kSkipNoSeekToLast | kSkipHashCuckoo |
kSkipMmapReads));
}
#ifndef ROCKSDB_LITE
TEST_F(DBIteratorTest, ManagedNonBlockingIteration) {
do {
ReadOptions non_blocking_opts, regular_opts;
Options options = CurrentOptions();
options.statistics = rocksdb::CreateDBStatistics();
non_blocking_opts.read_tier = kBlockCacheTier;
non_blocking_opts.managed = true;
CreateAndReopenWithCF({"pikachu"}, options);
// write one kv to the database.
ASSERT_OK(Put(1, "a", "b"));
// scan using non-blocking iterator. We should find it because
// it is in memtable.
Iterator* iter = db_->NewIterator(non_blocking_opts, handles_[1]);
int count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
ASSERT_OK(iter->status());
count++;
}
ASSERT_EQ(count, 1);
delete iter;
// flush memtable to storage. Now, the key should not be in the
// memtable neither in the block cache.
ASSERT_OK(Flush(1));
// verify that a non-blocking iterator does not find any
// kvs. Neither does it do any IOs to storage.
int64_t numopen = TestGetTickerCount(options, NO_FILE_OPENS);
int64_t cache_added = TestGetTickerCount(options, BLOCK_CACHE_ADD);
iter = db_->NewIterator(non_blocking_opts, handles_[1]);
count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
count++;
}
ASSERT_EQ(count, 0);
ASSERT_TRUE(iter->status().IsIncomplete());
ASSERT_EQ(numopen, TestGetTickerCount(options, NO_FILE_OPENS));
ASSERT_EQ(cache_added, TestGetTickerCount(options, BLOCK_CACHE_ADD));
delete iter;
// read in the specified block via a regular get
ASSERT_EQ(Get(1, "a"), "b");
// verify that we can find it via a non-blocking scan
numopen = TestGetTickerCount(options, NO_FILE_OPENS);
cache_added = TestGetTickerCount(options, BLOCK_CACHE_ADD);
iter = db_->NewIterator(non_blocking_opts, handles_[1]);
count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
ASSERT_OK(iter->status());
count++;
}
ASSERT_EQ(count, 1);
ASSERT_EQ(numopen, TestGetTickerCount(options, NO_FILE_OPENS));
ASSERT_EQ(cache_added, TestGetTickerCount(options, BLOCK_CACHE_ADD));
delete iter;
// This test verifies block cache behaviors, which is not used by plain
// table format.
// Exclude kHashCuckoo as it does not support iteration currently
} while (ChangeOptions(kSkipPlainTable | kSkipNoSeekToLast | kSkipHashCuckoo |
kSkipMmapReads));
}
#endif // ROCKSDB_LITE
TEST_F(DBIteratorTest, IterSeekBeforePrev) {
ASSERT_OK(Put("a", "b"));
ASSERT_OK(Put("c", "d"));
dbfull()->Flush(FlushOptions());
ASSERT_OK(Put("0", "f"));
ASSERT_OK(Put("1", "h"));
dbfull()->Flush(FlushOptions());
ASSERT_OK(Put("2", "j"));
auto iter = db_->NewIterator(ReadOptions());
iter->Seek(Slice("c"));
iter->Prev();
iter->Seek(Slice("a"));
iter->Prev();
delete iter;
}
namespace {
std::string MakeLongKey(size_t length, char c) {
return std::string(length, c);
}
} // namespace
TEST_F(DBIteratorTest, IterLongKeys) {
ASSERT_OK(Put(MakeLongKey(20, 0), "0"));
ASSERT_OK(Put(MakeLongKey(32, 2), "2"));
ASSERT_OK(Put("a", "b"));
dbfull()->Flush(FlushOptions());
ASSERT_OK(Put(MakeLongKey(50, 1), "1"));
ASSERT_OK(Put(MakeLongKey(127, 3), "3"));
ASSERT_OK(Put(MakeLongKey(64, 4), "4"));
auto iter = db_->NewIterator(ReadOptions());
// Create a key that needs to be skipped for Seq too new
iter->Seek(MakeLongKey(20, 0));
ASSERT_EQ(IterStatus(iter), MakeLongKey(20, 0) + "->0");
iter->Next();
ASSERT_EQ(IterStatus(iter), MakeLongKey(50, 1) + "->1");
iter->Next();
ASSERT_EQ(IterStatus(iter), MakeLongKey(32, 2) + "->2");
iter->Next();
ASSERT_EQ(IterStatus(iter), MakeLongKey(127, 3) + "->3");
iter->Next();
ASSERT_EQ(IterStatus(iter), MakeLongKey(64, 4) + "->4");
delete iter;
iter = db_->NewIterator(ReadOptions());
iter->Seek(MakeLongKey(50, 1));
ASSERT_EQ(IterStatus(iter), MakeLongKey(50, 1) + "->1");
iter->Next();
ASSERT_EQ(IterStatus(iter), MakeLongKey(32, 2) + "->2");
iter->Next();
ASSERT_EQ(IterStatus(iter), MakeLongKey(127, 3) + "->3");
delete iter;
}
TEST_F(DBIteratorTest, IterNextWithNewerSeq) {
ASSERT_OK(Put("0", "0"));
dbfull()->Flush(FlushOptions());
ASSERT_OK(Put("a", "b"));
ASSERT_OK(Put("c", "d"));
ASSERT_OK(Put("d", "e"));
auto iter = db_->NewIterator(ReadOptions());
// Create a key that needs to be skipped for Seq too new
for (uint64_t i = 0; i < last_options_.max_sequential_skip_in_iterations + 1;
i++) {
ASSERT_OK(Put("b", "f"));
}
iter->Seek(Slice("a"));
ASSERT_EQ(IterStatus(iter), "a->b");
iter->Next();
ASSERT_EQ(IterStatus(iter), "c->d");
delete iter;
}
TEST_F(DBIteratorTest, IterPrevWithNewerSeq) {
ASSERT_OK(Put("0", "0"));
dbfull()->Flush(FlushOptions());
ASSERT_OK(Put("a", "b"));
ASSERT_OK(Put("c", "d"));
ASSERT_OK(Put("d", "e"));
auto iter = db_->NewIterator(ReadOptions());
// Create a key that needs to be skipped for Seq too new
for (uint64_t i = 0; i < last_options_.max_sequential_skip_in_iterations + 1;
i++) {
ASSERT_OK(Put("b", "f"));
}
iter->Seek(Slice("d"));
ASSERT_EQ(IterStatus(iter), "d->e");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "c->d");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "a->b");
iter->Prev();
delete iter;
}
TEST_F(DBIteratorTest, IterPrevWithNewerSeq2) {
ASSERT_OK(Put("0", "0"));
dbfull()->Flush(FlushOptions());
ASSERT_OK(Put("a", "b"));
ASSERT_OK(Put("c", "d"));
ASSERT_OK(Put("d", "e"));
auto iter = db_->NewIterator(ReadOptions());
iter->Seek(Slice("c"));
ASSERT_EQ(IterStatus(iter), "c->d");
// Create a key that needs to be skipped for Seq too new
for (uint64_t i = 0; i < last_options_.max_sequential_skip_in_iterations + 1;
i++) {
ASSERT_OK(Put("b", "f"));
}
iter->Prev();
ASSERT_EQ(IterStatus(iter), "a->b");
iter->Prev();
delete iter;
}
TEST_F(DBIteratorTest, IterEmpty) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
Iterator* iter = db_->NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->Seek("foo");
ASSERT_EQ(IterStatus(iter), "(invalid)");
delete iter;
} while (ChangeCompactOptions());
}
TEST_F(DBIteratorTest, IterSingle) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
ASSERT_OK(Put(1, "a", "va"));
Iterator* iter = db_->NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->Seek("");
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->Seek("a");
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->Seek("b");
ASSERT_EQ(IterStatus(iter), "(invalid)");
delete iter;
} while (ChangeCompactOptions());
}
TEST_F(DBIteratorTest, IterMulti) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
ASSERT_OK(Put(1, "a", "va"));
ASSERT_OK(Put(1, "b", "vb"));
ASSERT_OK(Put(1, "c", "vc"));
Iterator* iter = db_->NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->Next();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->Seek("");
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Seek("a");
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Seek("ax");
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->Seek("b");
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->Seek("z");
ASSERT_EQ(IterStatus(iter), "(invalid)");
// Switch from reverse to forward
iter->SeekToLast();
iter->Prev();
iter->Prev();
iter->Next();
ASSERT_EQ(IterStatus(iter), "b->vb");
// Switch from forward to reverse
iter->SeekToFirst();
iter->Next();
iter->Next();
iter->Prev();
ASSERT_EQ(IterStatus(iter), "b->vb");
// Make sure iter stays at snapshot
ASSERT_OK(Put(1, "a", "va2"));
ASSERT_OK(Put(1, "a2", "va3"));
ASSERT_OK(Put(1, "b", "vb2"));
ASSERT_OK(Put(1, "c", "vc2"));
ASSERT_OK(Delete(1, "b"));
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->Next();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "b->vb");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
delete iter;
} while (ChangeCompactOptions());
}
// Check that we can skip over a run of user keys
// by using reseek rather than sequential scan
TEST_F(DBIteratorTest, IterReseek) {
anon::OptionsOverride options_override;
options_override.skip_policy = kSkipNoSnapshot;
Options options = CurrentOptions(options_override);
options.max_sequential_skip_in_iterations = 3;
options.create_if_missing = true;
options.statistics = rocksdb::CreateDBStatistics();
DestroyAndReopen(options);
CreateAndReopenWithCF({"pikachu"}, options);
// insert three keys with same userkey and verify that
// reseek is not invoked. For each of these test cases,
// verify that we can find the next key "b".
ASSERT_OK(Put(1, "a", "zero"));
ASSERT_OK(Put(1, "a", "one"));
ASSERT_OK(Put(1, "a", "two"));
ASSERT_OK(Put(1, "b", "bone"));
Iterator* iter = db_->NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 0);
ASSERT_EQ(IterStatus(iter), "a->two");
iter->Next();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 0);
ASSERT_EQ(IterStatus(iter), "b->bone");
delete iter;
// insert a total of three keys with same userkey and verify
// that reseek is still not invoked.
ASSERT_OK(Put(1, "a", "three"));
iter = db_->NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->three");
iter->Next();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 0);
ASSERT_EQ(IterStatus(iter), "b->bone");
delete iter;
// insert a total of four keys with same userkey and verify
// that reseek is invoked.
ASSERT_OK(Put(1, "a", "four"));
iter = db_->NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->four");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 0);
iter->Next();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION), 1);
ASSERT_EQ(IterStatus(iter), "b->bone");
delete iter;
// Testing reverse iterator
// At this point, we have three versions of "a" and one version of "b".
// The reseek statistics is already at 1.
int num_reseeks = static_cast<int>(
TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION));
// Insert another version of b and assert that reseek is not invoked
ASSERT_OK(Put(1, "b", "btwo"));
iter = db_->NewIterator(ReadOptions(), handles_[1]);
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "b->btwo");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION),
num_reseeks);
iter->Prev();
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION),
num_reseeks + 1);
ASSERT_EQ(IterStatus(iter), "a->four");
delete iter;
// insert two more versions of b. This makes a total of 4 versions
// of b and 4 versions of a.
ASSERT_OK(Put(1, "b", "bthree"));
ASSERT_OK(Put(1, "b", "bfour"));
iter = db_->NewIterator(ReadOptions(), handles_[1]);
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "b->bfour");
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION),
num_reseeks + 2);
iter->Prev();
// the previous Prev call should have invoked reseek
ASSERT_EQ(TestGetTickerCount(options, NUMBER_OF_RESEEKS_IN_ITERATION),
num_reseeks + 3);
ASSERT_EQ(IterStatus(iter), "a->four");
delete iter;
}
TEST_F(DBIteratorTest, IterSmallAndLargeMix) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
ASSERT_OK(Put(1, "a", "va"));
ASSERT_OK(Put(1, "b", std::string(100000, 'b')));
ASSERT_OK(Put(1, "c", "vc"));
ASSERT_OK(Put(1, "d", std::string(100000, 'd')));
ASSERT_OK(Put(1, "e", std::string(100000, 'e')));
Iterator* iter = db_->NewIterator(ReadOptions(), handles_[1]);
iter->SeekToFirst();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Next();
ASSERT_EQ(IterStatus(iter), "b->" + std::string(100000, 'b'));
iter->Next();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Next();
ASSERT_EQ(IterStatus(iter), "d->" + std::string(100000, 'd'));
iter->Next();
ASSERT_EQ(IterStatus(iter), "e->" + std::string(100000, 'e'));
iter->Next();
ASSERT_EQ(IterStatus(iter), "(invalid)");
iter->SeekToLast();
ASSERT_EQ(IterStatus(iter), "e->" + std::string(100000, 'e'));
iter->Prev();
ASSERT_EQ(IterStatus(iter), "d->" + std::string(100000, 'd'));
iter->Prev();
ASSERT_EQ(IterStatus(iter), "c->vc");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "b->" + std::string(100000, 'b'));
iter->Prev();
ASSERT_EQ(IterStatus(iter), "a->va");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "(invalid)");
delete iter;
} while (ChangeCompactOptions());
}
TEST_F(DBIteratorTest, IterMultiWithDelete) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
ASSERT_OK(Put(1, "ka", "va"));
ASSERT_OK(Put(1, "kb", "vb"));
ASSERT_OK(Put(1, "kc", "vc"));
ASSERT_OK(Delete(1, "kb"));
ASSERT_EQ("NOT_FOUND", Get(1, "kb"));
Iterator* iter = db_->NewIterator(ReadOptions(), handles_[1]);
iter->Seek("kc");
ASSERT_EQ(IterStatus(iter), "kc->vc");
if (!CurrentOptions().merge_operator) {
// TODO: merge operator does not support backward iteration yet
if (kPlainTableAllBytesPrefix != option_config_ &&
kBlockBasedTableWithWholeKeyHashIndex != option_config_ &&
kHashLinkList != option_config_) {
iter->Prev();
ASSERT_EQ(IterStatus(iter), "ka->va");
}
}
delete iter;
} while (ChangeOptions());
}
TEST_F(DBIteratorTest, IterPrevMaxSkip) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
for (int i = 0; i < 2; i++) {
ASSERT_OK(Put(1, "key1", "v1"));
ASSERT_OK(Put(1, "key2", "v2"));
ASSERT_OK(Put(1, "key3", "v3"));
ASSERT_OK(Put(1, "key4", "v4"));
ASSERT_OK(Put(1, "key5", "v5"));
}
VerifyIterLast("key5->v5", 1);
ASSERT_OK(Delete(1, "key5"));
VerifyIterLast("key4->v4", 1);
ASSERT_OK(Delete(1, "key4"));
VerifyIterLast("key3->v3", 1);
ASSERT_OK(Delete(1, "key3"));
VerifyIterLast("key2->v2", 1);
ASSERT_OK(Delete(1, "key2"));
VerifyIterLast("key1->v1", 1);
ASSERT_OK(Delete(1, "key1"));
VerifyIterLast("(invalid)", 1);
} while (ChangeOptions(kSkipMergePut | kSkipNoSeekToLast));
}
TEST_F(DBIteratorTest, IterWithSnapshot) {
anon::OptionsOverride options_override;
options_override.skip_policy = kSkipNoSnapshot;
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions(options_override));
ASSERT_OK(Put(1, "key1", "val1"));
ASSERT_OK(Put(1, "key2", "val2"));
ASSERT_OK(Put(1, "key3", "val3"));
ASSERT_OK(Put(1, "key4", "val4"));
ASSERT_OK(Put(1, "key5", "val5"));
const Snapshot* snapshot = db_->GetSnapshot();
ReadOptions options;
options.snapshot = snapshot;
Iterator* iter = db_->NewIterator(options, handles_[1]);
// Put more values after the snapshot
ASSERT_OK(Put(1, "key100", "val100"));
ASSERT_OK(Put(1, "key101", "val101"));
iter->Seek("key5");
ASSERT_EQ(IterStatus(iter), "key5->val5");
if (!CurrentOptions().merge_operator) {
// TODO: merge operator does not support backward iteration yet
if (kPlainTableAllBytesPrefix != option_config_ &&
kBlockBasedTableWithWholeKeyHashIndex != option_config_ &&
kHashLinkList != option_config_) {
iter->Prev();
ASSERT_EQ(IterStatus(iter), "key4->val4");
iter->Prev();
ASSERT_EQ(IterStatus(iter), "key3->val3");
iter->Next();
ASSERT_EQ(IterStatus(iter), "key4->val4");
iter->Next();
ASSERT_EQ(IterStatus(iter), "key5->val5");
}
iter->Next();
ASSERT_TRUE(!iter->Valid());
}
db_->ReleaseSnapshot(snapshot);
delete iter;
// skip as HashCuckooRep does not support snapshot
} while (ChangeOptions(kSkipHashCuckoo));
}
TEST_F(DBIteratorTest, IteratorPinsRef) {
do {
CreateAndReopenWithCF({"pikachu"}, CurrentOptions());
Put(1, "foo", "hello");
// Get iterator that will yield the current contents of the DB.
Iterator* iter = db_->NewIterator(ReadOptions(), handles_[1]);
// Write to force compactions
Put(1, "foo", "newvalue1");
for (int i = 0; i < 100; i++) {
// 100K values
ASSERT_OK(Put(1, Key(i), Key(i) + std::string(100000, 'v')));
}
Put(1, "foo", "newvalue2");
iter->SeekToFirst();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("foo", iter->key().ToString());
ASSERT_EQ("hello", iter->value().ToString());
iter->Next();
ASSERT_TRUE(!iter->Valid());
delete iter;
} while (ChangeCompactOptions());
}
TEST_F(DBIteratorTest, DBIteratorBoundTest) {
Options options = CurrentOptions();
options.env = env_;
options.create_if_missing = true;
options.prefix_extractor = nullptr;
DestroyAndReopen(options);
ASSERT_OK(Put("a", "0"));
ASSERT_OK(Put("foo", "bar"));
ASSERT_OK(Put("foo1", "bar1"));
ASSERT_OK(Put("g1", "0"));
// testing basic case with no iterate_upper_bound and no prefix_extractor
{
ReadOptions ro;
ro.iterate_upper_bound = nullptr;
std::unique_ptr<Iterator> iter(db_->NewIterator(ro));
iter->Seek("foo");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo1")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("g1")), 0);
}
// testing iterate_upper_bound and forward iterator
// to make sure it stops at bound
{
ReadOptions ro;
// iterate_upper_bound points beyond the last expected entry
Slice prefix("foo2");
ro.iterate_upper_bound = &prefix;
std::unique_ptr<Iterator> iter(db_->NewIterator(ro));
iter->Seek("foo");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("foo")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(("foo1")), 0);
iter->Next();
// should stop here...
ASSERT_TRUE(!iter->Valid());
}
// Testing SeekToLast with iterate_upper_bound set
{
ReadOptions ro;
Slice prefix("foo");
ro.iterate_upper_bound = &prefix;
std::unique_ptr<Iterator> iter(db_->NewIterator(ro));
iter->SeekToLast();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("a")), 0);
}
// prefix is the first letter of the key
options.prefix_extractor.reset(NewFixedPrefixTransform(1));
DestroyAndReopen(options);
ASSERT_OK(Put("a", "0"));
ASSERT_OK(Put("foo", "bar"));
ASSERT_OK(Put("foo1", "bar1"));
ASSERT_OK(Put("g1", "0"));
// testing with iterate_upper_bound and prefix_extractor
// Seek target and iterate_upper_bound are not is same prefix
// This should be an error
{
ReadOptions ro;
Slice upper_bound("g");
ro.iterate_upper_bound = &upper_bound;
std::unique_ptr<Iterator> iter(db_->NewIterator(ro));
iter->Seek("foo");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("foo", iter->key().ToString());
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("foo1", iter->key().ToString());
iter->Next();
ASSERT_TRUE(!iter->Valid());
}
// testing that iterate_upper_bound prevents iterating over deleted items
// if the bound has already reached
{
options.prefix_extractor = nullptr;
DestroyAndReopen(options);
ASSERT_OK(Put("a", "0"));
ASSERT_OK(Put("b", "0"));
ASSERT_OK(Put("b1", "0"));
ASSERT_OK(Put("c", "0"));
ASSERT_OK(Put("d", "0"));
ASSERT_OK(Put("e", "0"));
ASSERT_OK(Delete("c"));
ASSERT_OK(Delete("d"));
// base case with no bound
ReadOptions ro;
ro.iterate_upper_bound = nullptr;
std::unique_ptr<Iterator> iter(db_->NewIterator(ro));
iter->Seek("b");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("b")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(("b1")), 0);
perf_context.Reset();
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(static_cast<int>(perf_context.internal_delete_skipped_count), 2);
// now testing with iterate_bound
Slice prefix("c");
ro.iterate_upper_bound = &prefix;
iter.reset(db_->NewIterator(ro));
perf_context.Reset();
iter->Seek("b");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(Slice("b")), 0);
iter->Next();
ASSERT_TRUE(iter->Valid());
ASSERT_EQ(iter->key().compare(("b1")), 0);
iter->Next();
// the iteration should stop as soon as the bound key is reached
// even though the key is deleted
// hence internal_delete_skipped_count should be 0
ASSERT_TRUE(!iter->Valid());
ASSERT_EQ(static_cast<int>(perf_context.internal_delete_skipped_count), 0);
}
}
// TODO(3.13): fix the issue of Seek() + Prev() which might not necessary
// return the biggest key which is smaller than the seek key.
TEST_F(DBIteratorTest, PrevAfterMerge) {
Options options;
options.create_if_missing = true;
options.merge_operator = MergeOperators::CreatePutOperator();
DestroyAndReopen(options);
// write three entries with different keys using Merge()
WriteOptions wopts;
db_->Merge(wopts, "1", "data1");
db_->Merge(wopts, "2", "data2");
db_->Merge(wopts, "3", "data3");
std::unique_ptr<Iterator> it(db_->NewIterator(ReadOptions()));
it->Seek("2");
ASSERT_TRUE(it->Valid());
ASSERT_EQ("2", it->key().ToString());
it->Prev();
ASSERT_TRUE(it->Valid());
ASSERT_EQ("1", it->key().ToString());
}
TEST_F(DBIteratorTest, PinnedDataIteratorRandomized) {
enum TestConfig {
NORMAL,
CLOSE_AND_OPEN,
COMPACT_BEFORE_READ,
FLUSH_EVERY_1000,
MAX
};
// Generate Random data
Random rnd(301);
int puts = 100000;
int key_pool = static_cast<int>(puts * 0.7);
int key_size = 100;
int val_size = 1000;
int seeks_percentage = 20; // 20% of keys will be used to test seek()
int delete_percentage = 20; // 20% of keys will be deleted
int merge_percentage = 20; // 20% of keys will be added using Merge()
for (int run_config = 0; run_config < TestConfig::MAX; run_config++) {
Options options = CurrentOptions();
BlockBasedTableOptions table_options;
table_options.use_delta_encoding = false;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.merge_operator = MergeOperators::CreatePutOperator();
DestroyAndReopen(options);
std::vector<std::string> generated_keys(key_pool);
for (int i = 0; i < key_pool; i++) {
generated_keys[i] = RandomString(&rnd, key_size);
}
std::map<std::string, std::string> true_data;
std::vector<std::string> random_keys;
std::vector<std::string> deleted_keys;
for (int i = 0; i < puts; i++) {
auto& k = generated_keys[rnd.Next() % key_pool];
auto v = RandomString(&rnd, val_size);
// Insert data to true_data map and to DB
true_data[k] = v;
if (rnd.OneIn(static_cast<int>(100.0 / merge_percentage))) {
ASSERT_OK(db_->Merge(WriteOptions(), k, v));
} else {
ASSERT_OK(Put(k, v));
}
// Pick random keys to be used to test Seek()
if (rnd.OneIn(static_cast<int>(100.0 / seeks_percentage))) {
random_keys.push_back(k);
}
// Delete some random keys
if (rnd.OneIn(static_cast<int>(100.0 / delete_percentage))) {
deleted_keys.push_back(k);
true_data.erase(k);
ASSERT_OK(Delete(k));
}
if (run_config == TestConfig::FLUSH_EVERY_1000) {
if (i && i % 1000 == 0) {
Flush();
}
}
}
if (run_config == TestConfig::CLOSE_AND_OPEN) {
Close();
Reopen(options);
} else if (run_config == TestConfig::COMPACT_BEFORE_READ) {
db_->CompactRange(CompactRangeOptions(), nullptr, nullptr);
}
ReadOptions ro;
ro.pin_data = true;
auto iter = db_->NewIterator(ro);
{
// Test Seek to random keys
printf("Testing seek on %zu keys\n", random_keys.size());
std::vector<Slice> keys_slices;
std::vector<std::string> true_keys;
for (auto& k : random_keys) {
iter->Seek(k);
if (!iter->Valid()) {
ASSERT_EQ(true_data.lower_bound(k), true_data.end());
continue;
}
std::string prop_value;
ASSERT_OK(
iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("1", prop_value);
keys_slices.push_back(iter->key());
true_keys.push_back(true_data.lower_bound(k)->first);
}
for (size_t i = 0; i < keys_slices.size(); i++) {
ASSERT_EQ(keys_slices[i].ToString(), true_keys[i]);
}
}
{
// Test iterating all data forward
printf("Testing iterating forward on all keys\n");
std::vector<Slice> all_keys;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
std::string prop_value;
ASSERT_OK(
iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("1", prop_value);
all_keys.push_back(iter->key());
}
ASSERT_EQ(all_keys.size(), true_data.size());
// Verify that all keys slices are valid
auto data_iter = true_data.begin();
for (size_t i = 0; i < all_keys.size(); i++) {
ASSERT_EQ(all_keys[i].ToString(), data_iter->first);
data_iter++;
}
}
{
// Test iterating all data backward
printf("Testing iterating backward on all keys\n");
std::vector<Slice> all_keys;
for (iter->SeekToLast(); iter->Valid(); iter->Prev()) {
std::string prop_value;
ASSERT_OK(
iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("1", prop_value);
all_keys.push_back(iter->key());
}
ASSERT_EQ(all_keys.size(), true_data.size());
// Verify that all keys slices are valid (backward)
auto data_iter = true_data.rbegin();
for (size_t i = 0; i < all_keys.size(); i++) {
ASSERT_EQ(all_keys[i].ToString(), data_iter->first);
data_iter++;
}
}
delete iter;
}
}
#ifndef ROCKSDB_LITE
TEST_F(DBIteratorTest, PinnedDataIteratorMultipleFiles) {
Options options = CurrentOptions();
BlockBasedTableOptions table_options;
table_options.use_delta_encoding = false;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.disable_auto_compactions = true;
options.write_buffer_size = 1024 * 1024 * 10; // 10 Mb
DestroyAndReopen(options);
std::map<std::string, std::string> true_data;
// Generate 4 sst files in L2
Random rnd(301);
for (int i = 1; i <= 1000; i++) {
std::string k = Key(i * 3);
std::string v = RandomString(&rnd, 100);
ASSERT_OK(Put(k, v));
true_data[k] = v;
if (i % 250 == 0) {
ASSERT_OK(Flush());
}
}
ASSERT_EQ(FilesPerLevel(0), "4");
ASSERT_OK(db_->CompactRange(CompactRangeOptions(), nullptr, nullptr));
ASSERT_EQ(FilesPerLevel(0), "0,4");
// Generate 4 sst files in L0
for (int i = 1; i <= 1000; i++) {
std::string k = Key(i * 2);
std::string v = RandomString(&rnd, 100);
ASSERT_OK(Put(k, v));
true_data[k] = v;
if (i % 250 == 0) {
ASSERT_OK(Flush());
}
}
ASSERT_EQ(FilesPerLevel(0), "4,4");
// Add some keys/values in memtables
for (int i = 1; i <= 1000; i++) {
std::string k = Key(i);
std::string v = RandomString(&rnd, 100);
ASSERT_OK(Put(k, v));
true_data[k] = v;
}
ASSERT_EQ(FilesPerLevel(0), "4,4");
ReadOptions ro;
ro.pin_data = true;
auto iter = db_->NewIterator(ro);
std::vector<std::pair<Slice, std::string>> results;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
std::string prop_value;
ASSERT_OK(iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("1", prop_value);
results.emplace_back(iter->key(), iter->value().ToString());
}
ASSERT_EQ(results.size(), true_data.size());
auto data_iter = true_data.begin();
for (size_t i = 0; i < results.size(); i++, data_iter++) {
auto& kv = results[i];
ASSERT_EQ(kv.first, data_iter->first);
ASSERT_EQ(kv.second, data_iter->second);
}
delete iter;
}
#endif
TEST_F(DBIteratorTest, PinnedDataIteratorMergeOperator) {
Options options = CurrentOptions();
BlockBasedTableOptions table_options;
table_options.use_delta_encoding = false;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.merge_operator = MergeOperators::CreateUInt64AddOperator();
DestroyAndReopen(options);
std::string numbers[7];
for (int val = 0; val <= 6; val++) {
PutFixed64(numbers + val, val);
}
// +1 all keys in range [ 0 => 999]
for (int i = 0; i < 1000; i++) {
WriteOptions wo;
ASSERT_OK(db_->Merge(wo, Key(i), numbers[1]));
}
// +2 all keys divisible by 2 in range [ 0 => 999]
for (int i = 0; i < 1000; i += 2) {
WriteOptions wo;
ASSERT_OK(db_->Merge(wo, Key(i), numbers[2]));
}
// +3 all keys divisible by 5 in range [ 0 => 999]
for (int i = 0; i < 1000; i += 5) {
WriteOptions wo;
ASSERT_OK(db_->Merge(wo, Key(i), numbers[3]));
}
ReadOptions ro;
ro.pin_data = true;
auto iter = db_->NewIterator(ro);
std::vector<std::pair<Slice, std::string>> results;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
std::string prop_value;
ASSERT_OK(iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("1", prop_value);
results.emplace_back(iter->key(), iter->value().ToString());
}
ASSERT_EQ(results.size(), 1000);
for (size_t i = 0; i < results.size(); i++) {
auto& kv = results[i];
ASSERT_EQ(kv.first, Key(static_cast<int>(i)));
int expected_val = 1;
if (i % 2 == 0) {
expected_val += 2;
}
if (i % 5 == 0) {
expected_val += 3;
}
ASSERT_EQ(kv.second, numbers[expected_val]);
}
delete iter;
}
TEST_F(DBIteratorTest, PinnedDataIteratorReadAfterUpdate) {
Options options = CurrentOptions();
BlockBasedTableOptions table_options;
table_options.use_delta_encoding = false;
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.write_buffer_size = 100000;
DestroyAndReopen(options);
Random rnd(301);
std::map<std::string, std::string> true_data;
for (int i = 0; i < 1000; i++) {
std::string k = RandomString(&rnd, 10);
std::string v = RandomString(&rnd, 1000);
ASSERT_OK(Put(k, v));
true_data[k] = v;
}
ReadOptions ro;
ro.pin_data = true;
auto iter = db_->NewIterator(ro);
// Delete 50% of the keys and update the other 50%
for (auto& kv : true_data) {
if (rnd.OneIn(2)) {
ASSERT_OK(Delete(kv.first));
} else {
std::string new_val = RandomString(&rnd, 1000);
ASSERT_OK(Put(kv.first, new_val));
}
}
std::vector<std::pair<Slice, std::string>> results;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
std::string prop_value;
ASSERT_OK(iter->GetProperty("rocksdb.iterator.is-key-pinned", &prop_value));
ASSERT_EQ("1", prop_value);
results.emplace_back(iter->key(), iter->value().ToString());
}
auto data_iter = true_data.begin();
for (size_t i = 0; i < results.size(); i++, data_iter++) {
auto& kv = results[i];
ASSERT_EQ(kv.first, data_iter->first);
ASSERT_EQ(kv.second, data_iter->second);
}
delete iter;
}
Eliminate memcpy in Iterator::Prev() by pinning blocks for keys spanning multiple blocks Summary: This diff is stacked on top of this diff https://reviews.facebook.net/D56493 The current Iterator::Prev() implementation need to copy every value since the underlying Iterator may move after reading the value. This can be optimized by making sure that the block containing the value is pinned until the Iterator move. which will improve the throughput by up to 1.5X master ``` ==> 1000000_Keys_100Byte.txt <== readreverse : 0.449 micros/op 2225887 ops/sec; 246.2 MB/s readreverse : 0.433 micros/op 2311508 ops/sec; 255.7 MB/s readreverse : 0.436 micros/op 2294335 ops/sec; 253.8 MB/s readreverse : 0.471 micros/op 2121295 ops/sec; 234.7 MB/s readreverse : 0.465 micros/op 2152227 ops/sec; 238.1 MB/s readreverse : 0.454 micros/op 2203011 ops/sec; 243.7 MB/s readreverse : 0.451 micros/op 2216095 ops/sec; 245.2 MB/s readreverse : 0.462 micros/op 2162447 ops/sec; 239.2 MB/s readreverse : 0.476 micros/op 2099151 ops/sec; 232.2 MB/s readreverse : 0.472 micros/op 2120710 ops/sec; 234.6 MB/s avg : 242.34 MB/s ==> 1000000_Keys_1KB.txt <== readreverse : 1.013 micros/op 986793 ops/sec; 978.7 MB/s readreverse : 0.942 micros/op 1061136 ops/sec; 1052.5 MB/s readreverse : 0.951 micros/op 1051901 ops/sec; 1043.3 MB/s readreverse : 0.932 micros/op 1072894 ops/sec; 1064.1 MB/s readreverse : 1.024 micros/op 976720 ops/sec; 968.7 MB/s readreverse : 0.935 micros/op 1069169 ops/sec; 1060.4 MB/s readreverse : 1.012 micros/op 988132 ops/sec; 980.1 MB/s readreverse : 0.962 micros/op 1039579 ops/sec; 1031.1 MB/s readreverse : 0.991 micros/op 1008924 ops/sec; 1000.7 MB/s readreverse : 1.004 micros/op 996144 ops/sec; 988.0 MB/s avg : 1016.76 MB/s ==> 1000000_Keys_10KB.txt <== readreverse : 4.167 micros/op 239952 ops/sec; 2346.9 MB/s readreverse : 4.070 micros/op 245713 ops/sec; 2403.3 MB/s readreverse : 4.572 micros/op 218733 ops/sec; 2139.4 MB/s readreverse : 4.497 micros/op 222388 ops/sec; 2175.2 MB/s readreverse : 4.203 micros/op 237920 ops/sec; 2327.1 MB/s readreverse : 4.206 micros/op 237756 ops/sec; 2325.5 MB/s readreverse : 4.181 micros/op 239149 ops/sec; 2339.1 MB/s readreverse : 4.157 micros/op 240552 ops/sec; 2352.8 MB/s readreverse : 4.187 micros/op 238848 ops/sec; 2336.1 MB/s readreverse : 4.106 micros/op 243575 ops/sec; 2382.4 MB/s avg : 2312.78 MB/s ==> 100000_Keys_100KB.txt <== readreverse : 41.281 micros/op 24224 ops/sec; 2366.0 MB/s readreverse : 39.722 micros/op 25175 ops/sec; 2458.9 MB/s readreverse : 40.319 micros/op 24802 ops/sec; 2422.5 MB/s readreverse : 39.762 micros/op 25149 ops/sec; 2456.4 MB/s readreverse : 40.916 micros/op 24440 ops/sec; 2387.1 MB/s readreverse : 41.188 micros/op 24278 ops/sec; 2371.4 MB/s readreverse : 40.061 micros/op 24962 ops/sec; 2438.1 MB/s readreverse : 40.221 micros/op 24862 ops/sec; 2428.4 MB/s readreverse : 40.084 micros/op 24947 ops/sec; 2436.7 MB/s readreverse : 40.655 micros/op 24597 ops/sec; 2402.4 MB/s avg : 2416.79 MB/s ==> 10000_Keys_1MB.txt <== readreverse : 298.038 micros/op 3355 ops/sec; 3355.3 MB/s readreverse : 335.001 micros/op 2985 ops/sec; 2985.1 MB/s readreverse : 286.956 micros/op 3484 ops/sec; 3484.9 MB/s readreverse : 329.954 micros/op 3030 ops/sec; 3030.8 MB/s readreverse : 306.428 micros/op 3263 ops/sec; 3263.5 MB/s readreverse : 330.749 micros/op 3023 ops/sec; 3023.5 MB/s readreverse : 328.903 micros/op 3040 ops/sec; 3040.5 MB/s readreverse : 324.853 micros/op 3078 ops/sec; 3078.4 MB/s readreverse : 320.488 micros/op 3120 ops/sec; 3120.3 MB/s readreverse : 320.536 micros/op 3119 ops/sec; 3119.8 MB/s avg : 3150.21 MB/s ``` After memcpy elimination ``` ==> 1000000_Keys_100Byte.txt <== readreverse : 0.395 micros/op 2529890 ops/sec; 279.9 MB/s readreverse : 0.368 micros/op 2715922 ops/sec; 300.5 MB/s readreverse : 0.384 micros/op 2603929 ops/sec; 288.1 MB/s readreverse : 0.375 micros/op 2663286 ops/sec; 294.6 MB/s readreverse : 0.357 micros/op 2802180 ops/sec; 310.0 MB/s readreverse : 0.363 micros/op 2757684 ops/sec; 305.1 MB/s readreverse : 0.372 micros/op 2689603 ops/sec; 297.5 MB/s readreverse : 0.379 micros/op 2638599 ops/sec; 291.9 MB/s readreverse : 0.375 micros/op 2663803 ops/sec; 294.7 MB/s readreverse : 0.375 micros/op 2665579 ops/sec; 294.9 MB/s avg: 295.72 MB/s (1.22 X) ==> 1000000_Keys_1KB.txt <== readreverse : 0.879 micros/op 1138112 ops/sec; 1128.8 MB/s readreverse : 0.842 micros/op 1187998 ops/sec; 1178.3 MB/s readreverse : 0.837 micros/op 1194915 ops/sec; 1185.1 MB/s readreverse : 0.845 micros/op 1182983 ops/sec; 1173.3 MB/s readreverse : 0.877 micros/op 1140308 ops/sec; 1131.0 MB/s readreverse : 0.849 micros/op 1177581 ops/sec; 1168.0 MB/s readreverse : 0.915 micros/op 1093284 ops/sec; 1084.3 MB/s readreverse : 0.863 micros/op 1159418 ops/sec; 1149.9 MB/s readreverse : 0.895 micros/op 1117670 ops/sec; 1108.5 MB/s readreverse : 0.852 micros/op 1174116 ops/sec; 1164.5 MB/s avg: 1147.17 MB/s (1.12 X) ==> 1000000_Keys_10KB.txt <== readreverse : 3.870 micros/op 258386 ops/sec; 2527.2 MB/s readreverse : 3.568 micros/op 280296 ops/sec; 2741.5 MB/s readreverse : 4.005 micros/op 249694 ops/sec; 2442.2 MB/s readreverse : 3.550 micros/op 281719 ops/sec; 2755.5 MB/s readreverse : 3.562 micros/op 280758 ops/sec; 2746.1 MB/s readreverse : 3.507 micros/op 285125 ops/sec; 2788.8 MB/s readreverse : 3.463 micros/op 288739 ops/sec; 2824.1 MB/s readreverse : 3.428 micros/op 291734 ops/sec; 2853.4 MB/s readreverse : 3.553 micros/op 281491 ops/sec; 2753.2 MB/s readreverse : 3.535 micros/op 282885 ops/sec; 2766.9 MB/s avg : 2719.89 MB/s (1.17 X) ==> 100000_Keys_100KB.txt <== readreverse : 22.815 micros/op 43830 ops/sec; 4281.0 MB/s readreverse : 29.957 micros/op 33381 ops/sec; 3260.4 MB/s readreverse : 25.334 micros/op 39473 ops/sec; 3855.4 MB/s readreverse : 23.037 micros/op 43409 ops/sec; 4239.8 MB/s readreverse : 27.810 micros/op 35958 ops/sec; 3512.1 MB/s readreverse : 30.327 micros/op 32973 ops/sec; 3220.6 MB/s readreverse : 29.704 micros/op 33665 ops/sec; 3288.2 MB/s readreverse : 29.423 micros/op 33987 ops/sec; 3319.6 MB/s readreverse : 23.334 micros/op 42856 ops/sec; 4185.9 MB/s readreverse : 29.969 micros/op 33368 ops/sec; 3259.1 MB/s avg : 3642.21 MB/s (1.5 X) ==> 10000_Keys_1MB.txt <== readreverse : 244.748 micros/op 4085 ops/sec; 4085.9 MB/s readreverse : 230.208 micros/op 4343 ops/sec; 4344.0 MB/s readreverse : 235.655 micros/op 4243 ops/sec; 4243.6 MB/s readreverse : 235.730 micros/op 4242 ops/sec; 4242.2 MB/s readreverse : 237.346 micros/op 4213 ops/sec; 4213.3 MB/s readreverse : 227.306 micros/op 4399 ops/sec; 4399.4 MB/s readreverse : 194.957 micros/op 5129 ops/sec; 5129.4 MB/s readreverse : 238.359 micros/op 4195 ops/sec; 4195.4 MB/s readreverse : 221.588 micros/op 4512 ops/sec; 4513.0 MB/s readreverse : 235.911 micros/op 4238 ops/sec; 4239.0 MB/s avg : 4360.52 MB/s (1.38 X) ``` Test Plan: COMPILE_WITH_ASAN=1 make check -j64 Reviewers: andrewkr, yhchiang, sdong Reviewed By: sdong Subscribers: andrewkr, dhruba Differential Revision: https://reviews.facebook.net/D56511
9 years ago
TEST_F(DBIteratorTest, IterPrevKeyCrossingBlocks) {
Options options = CurrentOptions();
BlockBasedTableOptions table_options;
table_options.block_size = 1; // every block will contain one entry
options.table_factory.reset(NewBlockBasedTableFactory(table_options));
options.merge_operator = MergeOperators::CreateStringAppendTESTOperator();
options.disable_auto_compactions = true;
options.max_sequential_skip_in_iterations = 8;
DestroyAndReopen(options);
// Putting such deletes will force DBIter::Prev() to fallback to a Seek
for (int file_num = 0; file_num < 10; file_num++) {
ASSERT_OK(Delete("key4"));
ASSERT_OK(Flush());
}
// First File containing 5 blocks of puts
ASSERT_OK(Put("key1", "val1.0"));
ASSERT_OK(Put("key2", "val2.0"));
ASSERT_OK(Put("key3", "val3.0"));
ASSERT_OK(Put("key4", "val4.0"));
ASSERT_OK(Put("key5", "val5.0"));
ASSERT_OK(Flush());
// Second file containing 9 blocks of merge operands
ASSERT_OK(db_->Merge(WriteOptions(), "key1", "val1.1"));
ASSERT_OK(db_->Merge(WriteOptions(), "key1", "val1.2"));
ASSERT_OK(db_->Merge(WriteOptions(), "key2", "val2.1"));
ASSERT_OK(db_->Merge(WriteOptions(), "key2", "val2.2"));
ASSERT_OK(db_->Merge(WriteOptions(), "key2", "val2.3"));
ASSERT_OK(db_->Merge(WriteOptions(), "key3", "val3.1"));
ASSERT_OK(db_->Merge(WriteOptions(), "key3", "val3.2"));
ASSERT_OK(db_->Merge(WriteOptions(), "key3", "val3.3"));
ASSERT_OK(db_->Merge(WriteOptions(), "key3", "val3.4"));
ASSERT_OK(Flush());
{
ReadOptions ro;
ro.fill_cache = false;
Iterator* iter = db_->NewIterator(ro);
iter->SeekToLast();
ASSERT_EQ(iter->key().ToString(), "key5");
ASSERT_EQ(iter->value().ToString(), "val5.0");
iter->Prev();
ASSERT_EQ(iter->key().ToString(), "key4");
ASSERT_EQ(iter->value().ToString(), "val4.0");
iter->Prev();
ASSERT_EQ(iter->key().ToString(), "key3");
ASSERT_EQ(iter->value().ToString(), "val3.0,val3.1,val3.2,val3.3,val3.4");
iter->Prev();
ASSERT_EQ(iter->key().ToString(), "key2");
ASSERT_EQ(iter->value().ToString(), "val2.0,val2.1,val2.2,val2.3");
iter->Prev();
ASSERT_EQ(iter->key().ToString(), "key1");
ASSERT_EQ(iter->value().ToString(), "val1.0,val1.1,val1.2");
delete iter;
}
}
TEST_F(DBIteratorTest, IterPrevKeyCrossingBlocksRandomized) {
Options options = CurrentOptions();
options.merge_operator = MergeOperators::CreateStringAppendTESTOperator();
options.disable_auto_compactions = true;
options.level0_slowdown_writes_trigger = (1 << 30);
options.level0_stop_writes_trigger = (1 << 30);
options.max_sequential_skip_in_iterations = 8;
DestroyAndReopen(options);
const int kNumKeys = 500;
// Small number of merge operands to make sure that DBIter::Prev() dont
// fall back to Seek()
const int kNumMergeOperands = 3;
// Use value size that will make sure that every block contain 1 key
const int kValSize =
static_cast<int>(BlockBasedTableOptions().block_size) * 4;
// Percentage of keys that wont get merge operations
const int kNoMergeOpPercentage = 20;
// Percentage of keys that will be deleted
const int kDeletePercentage = 10;
// For half of the key range we will write multiple deletes first to
// force DBIter::Prev() to fall back to Seek()
for (int file_num = 0; file_num < 10; file_num++) {
for (int i = 0; i < kNumKeys; i += 2) {
ASSERT_OK(Delete(Key(i)));
}
ASSERT_OK(Flush());
}
Random rnd(301);
std::map<std::string, std::string> true_data;
std::string gen_key;
std::string gen_val;
for (int i = 0; i < kNumKeys; i++) {
gen_key = Key(i);
gen_val = RandomString(&rnd, kValSize);
ASSERT_OK(Put(gen_key, gen_val));
true_data[gen_key] = gen_val;
}
ASSERT_OK(Flush());
// Separate values and merge operands in different file so that we
// make sure that we dont merge them while flushing but actually
// merge them in the read path
for (int i = 0; i < kNumKeys; i++) {
if (rnd.OneIn(static_cast<int>(100.0 / kNoMergeOpPercentage))) {
// Dont give merge operations for some keys
continue;
}
for (int j = 0; j < kNumMergeOperands; j++) {
gen_key = Key(i);
gen_val = RandomString(&rnd, kValSize);
ASSERT_OK(db_->Merge(WriteOptions(), gen_key, gen_val));
true_data[gen_key] += "," + gen_val;
}
}
ASSERT_OK(Flush());
for (int i = 0; i < kNumKeys; i++) {
if (rnd.OneIn(static_cast<int>(100.0 / kDeletePercentage))) {
gen_key = Key(i);
ASSERT_OK(Delete(gen_key));
true_data.erase(gen_key);
}
}
ASSERT_OK(Flush());
{
ReadOptions ro;
ro.fill_cache = false;
Iterator* iter = db_->NewIterator(ro);
auto data_iter = true_data.rbegin();
for (iter->SeekToLast(); iter->Valid(); iter->Prev()) {
ASSERT_EQ(iter->key().ToString(), data_iter->first);
ASSERT_EQ(iter->value().ToString(), data_iter->second);
data_iter++;
}
ASSERT_EQ(data_iter, true_data.rend());
delete iter;
}
{
ReadOptions ro;
ro.fill_cache = false;
Iterator* iter = db_->NewIterator(ro);
auto data_iter = true_data.rbegin();
int entries_right = 0;
std::string seek_key;
for (iter->SeekToLast(); iter->Valid(); iter->Prev()) {
// Verify key/value of current position
ASSERT_EQ(iter->key().ToString(), data_iter->first);
ASSERT_EQ(iter->value().ToString(), data_iter->second);
bool restore_position_with_seek = rnd.Uniform(2);
if (restore_position_with_seek) {
seek_key = iter->key().ToString();
}
// Do some Next() operations the restore the iterator to orignal position
int next_count =
entries_right > 0 ? rnd.Uniform(std::min(entries_right, 10)) : 0;
for (int i = 0; i < next_count; i++) {
iter->Next();
data_iter--;
ASSERT_EQ(iter->key().ToString(), data_iter->first);
ASSERT_EQ(iter->value().ToString(), data_iter->second);
}
if (restore_position_with_seek) {
// Restore orignal position using Seek()
iter->Seek(seek_key);
for (int i = 0; i < next_count; i++) {
data_iter++;
}
ASSERT_EQ(iter->key().ToString(), data_iter->first);
ASSERT_EQ(iter->value().ToString(), data_iter->second);
} else {
// Restore original position using Prev()
for (int i = 0; i < next_count; i++) {
iter->Prev();
data_iter++;
ASSERT_EQ(iter->key().ToString(), data_iter->first);
ASSERT_EQ(iter->value().ToString(), data_iter->second);
}
}
entries_right++;
data_iter++;
}
ASSERT_EQ(data_iter, true_data.rend());
delete iter;
}
Eliminate memcpy in Iterator::Prev() by pinning blocks for keys spanning multiple blocks Summary: This diff is stacked on top of this diff https://reviews.facebook.net/D56493 The current Iterator::Prev() implementation need to copy every value since the underlying Iterator may move after reading the value. This can be optimized by making sure that the block containing the value is pinned until the Iterator move. which will improve the throughput by up to 1.5X master ``` ==> 1000000_Keys_100Byte.txt <== readreverse : 0.449 micros/op 2225887 ops/sec; 246.2 MB/s readreverse : 0.433 micros/op 2311508 ops/sec; 255.7 MB/s readreverse : 0.436 micros/op 2294335 ops/sec; 253.8 MB/s readreverse : 0.471 micros/op 2121295 ops/sec; 234.7 MB/s readreverse : 0.465 micros/op 2152227 ops/sec; 238.1 MB/s readreverse : 0.454 micros/op 2203011 ops/sec; 243.7 MB/s readreverse : 0.451 micros/op 2216095 ops/sec; 245.2 MB/s readreverse : 0.462 micros/op 2162447 ops/sec; 239.2 MB/s readreverse : 0.476 micros/op 2099151 ops/sec; 232.2 MB/s readreverse : 0.472 micros/op 2120710 ops/sec; 234.6 MB/s avg : 242.34 MB/s ==> 1000000_Keys_1KB.txt <== readreverse : 1.013 micros/op 986793 ops/sec; 978.7 MB/s readreverse : 0.942 micros/op 1061136 ops/sec; 1052.5 MB/s readreverse : 0.951 micros/op 1051901 ops/sec; 1043.3 MB/s readreverse : 0.932 micros/op 1072894 ops/sec; 1064.1 MB/s readreverse : 1.024 micros/op 976720 ops/sec; 968.7 MB/s readreverse : 0.935 micros/op 1069169 ops/sec; 1060.4 MB/s readreverse : 1.012 micros/op 988132 ops/sec; 980.1 MB/s readreverse : 0.962 micros/op 1039579 ops/sec; 1031.1 MB/s readreverse : 0.991 micros/op 1008924 ops/sec; 1000.7 MB/s readreverse : 1.004 micros/op 996144 ops/sec; 988.0 MB/s avg : 1016.76 MB/s ==> 1000000_Keys_10KB.txt <== readreverse : 4.167 micros/op 239952 ops/sec; 2346.9 MB/s readreverse : 4.070 micros/op 245713 ops/sec; 2403.3 MB/s readreverse : 4.572 micros/op 218733 ops/sec; 2139.4 MB/s readreverse : 4.497 micros/op 222388 ops/sec; 2175.2 MB/s readreverse : 4.203 micros/op 237920 ops/sec; 2327.1 MB/s readreverse : 4.206 micros/op 237756 ops/sec; 2325.5 MB/s readreverse : 4.181 micros/op 239149 ops/sec; 2339.1 MB/s readreverse : 4.157 micros/op 240552 ops/sec; 2352.8 MB/s readreverse : 4.187 micros/op 238848 ops/sec; 2336.1 MB/s readreverse : 4.106 micros/op 243575 ops/sec; 2382.4 MB/s avg : 2312.78 MB/s ==> 100000_Keys_100KB.txt <== readreverse : 41.281 micros/op 24224 ops/sec; 2366.0 MB/s readreverse : 39.722 micros/op 25175 ops/sec; 2458.9 MB/s readreverse : 40.319 micros/op 24802 ops/sec; 2422.5 MB/s readreverse : 39.762 micros/op 25149 ops/sec; 2456.4 MB/s readreverse : 40.916 micros/op 24440 ops/sec; 2387.1 MB/s readreverse : 41.188 micros/op 24278 ops/sec; 2371.4 MB/s readreverse : 40.061 micros/op 24962 ops/sec; 2438.1 MB/s readreverse : 40.221 micros/op 24862 ops/sec; 2428.4 MB/s readreverse : 40.084 micros/op 24947 ops/sec; 2436.7 MB/s readreverse : 40.655 micros/op 24597 ops/sec; 2402.4 MB/s avg : 2416.79 MB/s ==> 10000_Keys_1MB.txt <== readreverse : 298.038 micros/op 3355 ops/sec; 3355.3 MB/s readreverse : 335.001 micros/op 2985 ops/sec; 2985.1 MB/s readreverse : 286.956 micros/op 3484 ops/sec; 3484.9 MB/s readreverse : 329.954 micros/op 3030 ops/sec; 3030.8 MB/s readreverse : 306.428 micros/op 3263 ops/sec; 3263.5 MB/s readreverse : 330.749 micros/op 3023 ops/sec; 3023.5 MB/s readreverse : 328.903 micros/op 3040 ops/sec; 3040.5 MB/s readreverse : 324.853 micros/op 3078 ops/sec; 3078.4 MB/s readreverse : 320.488 micros/op 3120 ops/sec; 3120.3 MB/s readreverse : 320.536 micros/op 3119 ops/sec; 3119.8 MB/s avg : 3150.21 MB/s ``` After memcpy elimination ``` ==> 1000000_Keys_100Byte.txt <== readreverse : 0.395 micros/op 2529890 ops/sec; 279.9 MB/s readreverse : 0.368 micros/op 2715922 ops/sec; 300.5 MB/s readreverse : 0.384 micros/op 2603929 ops/sec; 288.1 MB/s readreverse : 0.375 micros/op 2663286 ops/sec; 294.6 MB/s readreverse : 0.357 micros/op 2802180 ops/sec; 310.0 MB/s readreverse : 0.363 micros/op 2757684 ops/sec; 305.1 MB/s readreverse : 0.372 micros/op 2689603 ops/sec; 297.5 MB/s readreverse : 0.379 micros/op 2638599 ops/sec; 291.9 MB/s readreverse : 0.375 micros/op 2663803 ops/sec; 294.7 MB/s readreverse : 0.375 micros/op 2665579 ops/sec; 294.9 MB/s avg: 295.72 MB/s (1.22 X) ==> 1000000_Keys_1KB.txt <== readreverse : 0.879 micros/op 1138112 ops/sec; 1128.8 MB/s readreverse : 0.842 micros/op 1187998 ops/sec; 1178.3 MB/s readreverse : 0.837 micros/op 1194915 ops/sec; 1185.1 MB/s readreverse : 0.845 micros/op 1182983 ops/sec; 1173.3 MB/s readreverse : 0.877 micros/op 1140308 ops/sec; 1131.0 MB/s readreverse : 0.849 micros/op 1177581 ops/sec; 1168.0 MB/s readreverse : 0.915 micros/op 1093284 ops/sec; 1084.3 MB/s readreverse : 0.863 micros/op 1159418 ops/sec; 1149.9 MB/s readreverse : 0.895 micros/op 1117670 ops/sec; 1108.5 MB/s readreverse : 0.852 micros/op 1174116 ops/sec; 1164.5 MB/s avg: 1147.17 MB/s (1.12 X) ==> 1000000_Keys_10KB.txt <== readreverse : 3.870 micros/op 258386 ops/sec; 2527.2 MB/s readreverse : 3.568 micros/op 280296 ops/sec; 2741.5 MB/s readreverse : 4.005 micros/op 249694 ops/sec; 2442.2 MB/s readreverse : 3.550 micros/op 281719 ops/sec; 2755.5 MB/s readreverse : 3.562 micros/op 280758 ops/sec; 2746.1 MB/s readreverse : 3.507 micros/op 285125 ops/sec; 2788.8 MB/s readreverse : 3.463 micros/op 288739 ops/sec; 2824.1 MB/s readreverse : 3.428 micros/op 291734 ops/sec; 2853.4 MB/s readreverse : 3.553 micros/op 281491 ops/sec; 2753.2 MB/s readreverse : 3.535 micros/op 282885 ops/sec; 2766.9 MB/s avg : 2719.89 MB/s (1.17 X) ==> 100000_Keys_100KB.txt <== readreverse : 22.815 micros/op 43830 ops/sec; 4281.0 MB/s readreverse : 29.957 micros/op 33381 ops/sec; 3260.4 MB/s readreverse : 25.334 micros/op 39473 ops/sec; 3855.4 MB/s readreverse : 23.037 micros/op 43409 ops/sec; 4239.8 MB/s readreverse : 27.810 micros/op 35958 ops/sec; 3512.1 MB/s readreverse : 30.327 micros/op 32973 ops/sec; 3220.6 MB/s readreverse : 29.704 micros/op 33665 ops/sec; 3288.2 MB/s readreverse : 29.423 micros/op 33987 ops/sec; 3319.6 MB/s readreverse : 23.334 micros/op 42856 ops/sec; 4185.9 MB/s readreverse : 29.969 micros/op 33368 ops/sec; 3259.1 MB/s avg : 3642.21 MB/s (1.5 X) ==> 10000_Keys_1MB.txt <== readreverse : 244.748 micros/op 4085 ops/sec; 4085.9 MB/s readreverse : 230.208 micros/op 4343 ops/sec; 4344.0 MB/s readreverse : 235.655 micros/op 4243 ops/sec; 4243.6 MB/s readreverse : 235.730 micros/op 4242 ops/sec; 4242.2 MB/s readreverse : 237.346 micros/op 4213 ops/sec; 4213.3 MB/s readreverse : 227.306 micros/op 4399 ops/sec; 4399.4 MB/s readreverse : 194.957 micros/op 5129 ops/sec; 5129.4 MB/s readreverse : 238.359 micros/op 4195 ops/sec; 4195.4 MB/s readreverse : 221.588 micros/op 4512 ops/sec; 4513.0 MB/s readreverse : 235.911 micros/op 4238 ops/sec; 4239.0 MB/s avg : 4360.52 MB/s (1.38 X) ``` Test Plan: COMPILE_WITH_ASAN=1 make check -j64 Reviewers: andrewkr, yhchiang, sdong Reviewed By: sdong Subscribers: andrewkr, dhruba Differential Revision: https://reviews.facebook.net/D56511
9 years ago
}
TEST_F(DBIteratorTest, IteratorWithLocalStatistics) {
Options options = CurrentOptions();
options.statistics = rocksdb::CreateDBStatistics();
DestroyAndReopen(options);
Random rnd(301);
for (int i = 0; i < 1000; i++) {
// Key 10 bytes / Value 10 bytes
ASSERT_OK(Put(RandomString(&rnd, 10), RandomString(&rnd, 10)));
}
std::atomic<uint64_t> total_next(0);
std::atomic<uint64_t> total_next_found(0);
std::atomic<uint64_t> total_prev(0);
std::atomic<uint64_t> total_prev_found(0);
std::atomic<uint64_t> total_bytes(0);
std::vector<std::thread> threads;
std::function<void()> reader_func_next = [&]() {
Iterator* iter = db_->NewIterator(ReadOptions());
iter->SeekToFirst();
// Seek will bump ITER_BYTES_READ
total_bytes += iter->key().size();
total_bytes += iter->value().size();
while (true) {
iter->Next();
total_next++;
if (!iter->Valid()) {
break;
}
total_next_found++;
total_bytes += iter->key().size();
total_bytes += iter->value().size();
}
delete iter;
};
std::function<void()> reader_func_prev = [&]() {
Iterator* iter = db_->NewIterator(ReadOptions());
iter->SeekToLast();
// Seek will bump ITER_BYTES_READ
total_bytes += iter->key().size();
total_bytes += iter->value().size();
while (true) {
iter->Prev();
total_prev++;
if (!iter->Valid()) {
break;
}
total_prev_found++;
total_bytes += iter->key().size();
total_bytes += iter->value().size();
}
delete iter;
};
for (int i = 0; i < 10; i++) {
threads.emplace_back(reader_func_next);
}
for (int i = 0; i < 15; i++) {
threads.emplace_back(reader_func_prev);
}
for (auto& t : threads) {
t.join();
}
ASSERT_EQ(TestGetTickerCount(options, NUMBER_DB_NEXT), total_next);
ASSERT_EQ(TestGetTickerCount(options, NUMBER_DB_NEXT_FOUND),
total_next_found);
ASSERT_EQ(TestGetTickerCount(options, NUMBER_DB_PREV), total_prev);
ASSERT_EQ(TestGetTickerCount(options, NUMBER_DB_PREV_FOUND),
total_prev_found);
ASSERT_EQ(TestGetTickerCount(options, ITER_BYTES_READ), total_bytes);
}
TEST_F(DBIteratorTest, ReadAhead) {
Options options;
auto env = new SpecialEnv(Env::Default());
env->count_random_reads_ = true;
options.env = env;
options.disable_auto_compactions = true;
options.write_buffer_size = 4 << 20;
options.statistics = rocksdb::CreateDBStatistics();
BlockBasedTableOptions table_options;
table_options.block_size = 1024;
table_options.no_block_cache = true;
options.table_factory.reset(new BlockBasedTableFactory(table_options));
Reopen(options);
std::string value(1024, 'a');
for (int i = 0; i < 100; i++) {
Put(Key(i), value);
}
ASSERT_OK(Flush());
MoveFilesToLevel(2);
for (int i = 0; i < 100; i++) {
Put(Key(i), value);
}
ASSERT_OK(Flush());
MoveFilesToLevel(1);
for (int i = 0; i < 100; i++) {
Put(Key(i), value);
}
ASSERT_OK(Flush());
ASSERT_EQ("1,1,1", FilesPerLevel());
env->random_read_bytes_counter_ = 0;
options.statistics->setTickerCount(NO_FILE_OPENS, 0);
ReadOptions read_options;
auto* iter = db_->NewIterator(read_options);
iter->SeekToFirst();
int64_t num_file_opens = TestGetTickerCount(options, NO_FILE_OPENS);
int64_t bytes_read = env->random_read_bytes_counter_;
delete iter;
env->random_read_bytes_counter_ = 0;
options.statistics->setTickerCount(NO_FILE_OPENS, 0);
read_options.readahead_size = 1024 * 10;
iter = db_->NewIterator(read_options);
iter->SeekToFirst();
int64_t num_file_opens_readahead = TestGetTickerCount(options, NO_FILE_OPENS);
int64_t bytes_read_readahead = env->random_read_bytes_counter_;
delete iter;
ASSERT_EQ(num_file_opens + 3, num_file_opens_readahead);
ASSERT_GT(bytes_read_readahead, bytes_read);
ASSERT_GT(bytes_read_readahead, read_options.readahead_size * 3);
// Verify correctness.
iter = db_->NewIterator(read_options);
int count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
ASSERT_EQ(value, iter->value());
count++;
}
ASSERT_EQ(100, count);
for (int i = 0; i < 100; i++) {
iter->Seek(Key(i));
ASSERT_EQ(value, iter->value());
}
delete iter;
}
} // namespace rocksdb
int main(int argc, char** argv) {
rocksdb::port::InstallStackTraceHandler();
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}