rocksdb/db/merge_helper_test.cc
Yanqin Jin 7d26e4c5a3 Basic Support for Merge with user-defined timestamp (#10819)
Summary:
This PR implements the originally disabled `Merge()` APIs when user-defined timestamp is enabled.

Simplest usage:
```cpp
// assume string append merge op is used with '.' as delimiter.
// ts1 < ts2
db->Put(WriteOptions(), "key", ts1, "v0");
db->Merge(WriteOptions(), "key", ts2, "1");
ReadOptions ro;
ro.timestamp = &ts2;
db->Get(ro, "key", &value);
ASSERT_EQ("v0.1", value);
```

Some code comments are added for clarity.

Note: support for timestamp in `DB::GetMergeOperands()` will be done in a follow-up PR.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10819

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D40603195

Pulled By: riversand963

fbshipit-source-id: f96d6f183258f3392d80377025529f7660503013
2022-10-31 22:28:58 -07:00

299 lines
12 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#include "db/merge_helper.h"
#include <algorithm>
#include <string>
#include <vector>
#include "db/dbformat.h"
#include "rocksdb/comparator.h"
#include "test_util/testharness.h"
#include "test_util/testutil.h"
#include "util/coding.h"
#include "util/vector_iterator.h"
#include "utilities/merge_operators.h"
namespace ROCKSDB_NAMESPACE {
class MergeHelperTest : public testing::Test {
public:
MergeHelperTest() : icmp_(BytewiseComparator()) { env_ = Env::Default(); }
~MergeHelperTest() override = default;
Status Run(SequenceNumber stop_before, bool at_bottom,
SequenceNumber latest_snapshot = 0) {
iter_.reset(new VectorIterator(ks_, vs_, &icmp_));
iter_->SeekToFirst();
merge_helper_.reset(new MergeHelper(env_, icmp_.user_comparator(),
merge_op_.get(), filter_.get(), nullptr,
false, latest_snapshot));
return merge_helper_->MergeUntil(
iter_.get(), nullptr /* range_del_agg */, stop_before, at_bottom,
false /* allow_data_in_errors */, nullptr /* blob_fetcher */,
nullptr /* full_history_ts_low */, nullptr /* prefetch_buffers */,
nullptr /* c_iter_stats */);
}
void AddKeyVal(const std::string& user_key, const SequenceNumber& seq,
const ValueType& t, const std::string& val,
bool corrupt = false) {
InternalKey ikey(user_key, seq, t);
if (corrupt) {
test::CorruptKeyType(&ikey);
}
ks_.push_back(ikey.Encode().ToString());
vs_.push_back(val);
}
Env* env_;
InternalKeyComparator icmp_;
std::unique_ptr<VectorIterator> iter_;
std::shared_ptr<MergeOperator> merge_op_;
std::unique_ptr<MergeHelper> merge_helper_;
std::vector<std::string> ks_;
std::vector<std::string> vs_;
std::unique_ptr<test::FilterNumber> filter_;
};
// If MergeHelper encounters a new key on the last level, we know that
// the key has no more history and it can merge keys.
TEST_F(MergeHelperTest, MergeAtBottomSuccess) {
merge_op_ = MergeOperators::CreateUInt64AddOperator();
AddKeyVal("a", 20, kTypeMerge, test::EncodeInt(1U));
AddKeyVal("a", 10, kTypeMerge, test::EncodeInt(3U));
AddKeyVal("b", 10, kTypeMerge, test::EncodeInt(4U)); // <- iter_ after merge
ASSERT_TRUE(Run(0, true).ok());
ASSERT_EQ(ks_[2], iter_->key());
ASSERT_EQ(test::KeyStr("a", 20, kTypeValue), merge_helper_->keys()[0]);
ASSERT_EQ(test::EncodeInt(4U), merge_helper_->values()[0]);
ASSERT_EQ(1U, merge_helper_->keys().size());
ASSERT_EQ(1U, merge_helper_->values().size());
}
// Merging with a value results in a successful merge.
TEST_F(MergeHelperTest, MergeValue) {
merge_op_ = MergeOperators::CreateUInt64AddOperator();
AddKeyVal("a", 40, kTypeMerge, test::EncodeInt(1U));
AddKeyVal("a", 30, kTypeMerge, test::EncodeInt(3U));
AddKeyVal("a", 20, kTypeValue, test::EncodeInt(4U)); // <- iter_ after merge
AddKeyVal("a", 10, kTypeMerge, test::EncodeInt(1U));
ASSERT_TRUE(Run(0, false).ok());
ASSERT_EQ(ks_[3], iter_->key());
ASSERT_EQ(test::KeyStr("a", 40, kTypeValue), merge_helper_->keys()[0]);
ASSERT_EQ(test::EncodeInt(8U), merge_helper_->values()[0]);
ASSERT_EQ(1U, merge_helper_->keys().size());
ASSERT_EQ(1U, merge_helper_->values().size());
}
// Merging stops before a snapshot.
TEST_F(MergeHelperTest, SnapshotBeforeValue) {
merge_op_ = MergeOperators::CreateUInt64AddOperator();
AddKeyVal("a", 50, kTypeMerge, test::EncodeInt(1U));
AddKeyVal("a", 40, kTypeMerge, test::EncodeInt(3U)); // <- iter_ after merge
AddKeyVal("a", 30, kTypeMerge, test::EncodeInt(1U));
AddKeyVal("a", 20, kTypeValue, test::EncodeInt(4U));
AddKeyVal("a", 10, kTypeMerge, test::EncodeInt(1U));
ASSERT_TRUE(Run(31, true).IsMergeInProgress());
ASSERT_EQ(ks_[2], iter_->key());
ASSERT_EQ(test::KeyStr("a", 50, kTypeMerge), merge_helper_->keys()[0]);
ASSERT_EQ(test::EncodeInt(4U), merge_helper_->values()[0]);
ASSERT_EQ(1U, merge_helper_->keys().size());
ASSERT_EQ(1U, merge_helper_->values().size());
}
// MergeHelper preserves the operand stack for merge operators that
// cannot do a partial merge.
TEST_F(MergeHelperTest, NoPartialMerge) {
merge_op_ = MergeOperators::CreateStringAppendTESTOperator();
AddKeyVal("a", 50, kTypeMerge, "v2");
AddKeyVal("a", 40, kTypeMerge, "v"); // <- iter_ after merge
AddKeyVal("a", 30, kTypeMerge, "v");
ASSERT_TRUE(Run(31, true).IsMergeInProgress());
ASSERT_EQ(ks_[2], iter_->key());
ASSERT_EQ(test::KeyStr("a", 40, kTypeMerge), merge_helper_->keys()[0]);
ASSERT_EQ("v", merge_helper_->values()[0]);
ASSERT_EQ(test::KeyStr("a", 50, kTypeMerge), merge_helper_->keys()[1]);
ASSERT_EQ("v2", merge_helper_->values()[1]);
ASSERT_EQ(2U, merge_helper_->keys().size());
ASSERT_EQ(2U, merge_helper_->values().size());
}
// A single operand can not be merged.
TEST_F(MergeHelperTest, SingleOperand) {
merge_op_ = MergeOperators::CreateUInt64AddOperator();
AddKeyVal("a", 50, kTypeMerge, test::EncodeInt(1U));
ASSERT_TRUE(Run(31, false).IsMergeInProgress());
ASSERT_FALSE(iter_->Valid());
ASSERT_EQ(test::KeyStr("a", 50, kTypeMerge), merge_helper_->keys()[0]);
ASSERT_EQ(test::EncodeInt(1U), merge_helper_->values()[0]);
ASSERT_EQ(1U, merge_helper_->keys().size());
ASSERT_EQ(1U, merge_helper_->values().size());
}
// Merging with a deletion turns the deletion into a value
TEST_F(MergeHelperTest, MergeDeletion) {
merge_op_ = MergeOperators::CreateUInt64AddOperator();
AddKeyVal("a", 30, kTypeMerge, test::EncodeInt(3U));
AddKeyVal("a", 20, kTypeDeletion, "");
ASSERT_TRUE(Run(15, false).ok());
ASSERT_FALSE(iter_->Valid());
ASSERT_EQ(test::KeyStr("a", 30, kTypeValue), merge_helper_->keys()[0]);
ASSERT_EQ(test::EncodeInt(3U), merge_helper_->values()[0]);
ASSERT_EQ(1U, merge_helper_->keys().size());
ASSERT_EQ(1U, merge_helper_->values().size());
}
// The merge helper stops upon encountering a corrupt key
TEST_F(MergeHelperTest, CorruptKey) {
merge_op_ = MergeOperators::CreateUInt64AddOperator();
AddKeyVal("a", 30, kTypeMerge, test::EncodeInt(3U));
AddKeyVal("a", 25, kTypeMerge, test::EncodeInt(1U));
// Corrupt key
AddKeyVal("a", 20, kTypeDeletion, "", true); // <- iter_ after merge
ASSERT_TRUE(Run(15, false).IsMergeInProgress());
ASSERT_EQ(ks_[2], iter_->key());
ASSERT_EQ(test::KeyStr("a", 30, kTypeMerge), merge_helper_->keys()[0]);
ASSERT_EQ(test::EncodeInt(4U), merge_helper_->values()[0]);
ASSERT_EQ(1U, merge_helper_->keys().size());
ASSERT_EQ(1U, merge_helper_->values().size());
}
// The compaction filter is called on every merge operand
TEST_F(MergeHelperTest, FilterMergeOperands) {
merge_op_ = MergeOperators::CreateUInt64AddOperator();
filter_.reset(new test::FilterNumber(5U));
AddKeyVal("a", 30, kTypeMerge, test::EncodeInt(3U));
AddKeyVal("a", 29, kTypeMerge, test::EncodeInt(5U)); // Filtered
AddKeyVal("a", 28, kTypeMerge, test::EncodeInt(3U));
AddKeyVal("a", 27, kTypeMerge, test::EncodeInt(1U));
AddKeyVal("a", 26, kTypeMerge, test::EncodeInt(5U)); // Filtered
AddKeyVal("a", 25, kTypeValue, test::EncodeInt(1U));
ASSERT_TRUE(Run(15, false).ok());
ASSERT_FALSE(iter_->Valid());
MergeOutputIterator merge_output_iter(merge_helper_.get());
merge_output_iter.SeekToFirst();
ASSERT_EQ(test::KeyStr("a", 30, kTypeValue),
merge_output_iter.key().ToString());
ASSERT_EQ(test::EncodeInt(8U), merge_output_iter.value().ToString());
merge_output_iter.Next();
ASSERT_FALSE(merge_output_iter.Valid());
}
TEST_F(MergeHelperTest, FilterAllMergeOperands) {
merge_op_ = MergeOperators::CreateUInt64AddOperator();
filter_.reset(new test::FilterNumber(5U));
AddKeyVal("a", 30, kTypeMerge, test::EncodeInt(5U));
AddKeyVal("a", 29, kTypeMerge, test::EncodeInt(5U));
AddKeyVal("a", 28, kTypeMerge, test::EncodeInt(5U));
AddKeyVal("a", 27, kTypeMerge, test::EncodeInt(5U));
AddKeyVal("a", 26, kTypeMerge, test::EncodeInt(5U));
AddKeyVal("a", 25, kTypeMerge, test::EncodeInt(5U));
// filtered out all
ASSERT_TRUE(Run(15, false).ok());
ASSERT_FALSE(iter_->Valid());
MergeOutputIterator merge_output_iter(merge_helper_.get());
merge_output_iter.SeekToFirst();
ASSERT_FALSE(merge_output_iter.Valid());
// we have one operand that will survive because it's a delete
AddKeyVal("a", 24, kTypeDeletion, test::EncodeInt(5U));
AddKeyVal("b", 23, kTypeValue, test::EncodeInt(5U));
ASSERT_TRUE(Run(15, true).ok());
merge_output_iter = MergeOutputIterator(merge_helper_.get());
ASSERT_TRUE(iter_->Valid());
merge_output_iter.SeekToFirst();
ASSERT_FALSE(merge_output_iter.Valid());
// when all merge operands are filtered out, we leave the iterator pointing to
// the Put/Delete that survived
ASSERT_EQ(test::KeyStr("a", 24, kTypeDeletion), iter_->key().ToString());
ASSERT_EQ(test::EncodeInt(5U), iter_->value().ToString());
}
// Make sure that merge operands are filtered at the beginning
TEST_F(MergeHelperTest, FilterFirstMergeOperand) {
merge_op_ = MergeOperators::CreateUInt64AddOperator();
filter_.reset(new test::FilterNumber(5U));
AddKeyVal("a", 31, kTypeMerge, test::EncodeInt(5U)); // Filtered
AddKeyVal("a", 30, kTypeMerge, test::EncodeInt(5U)); // Filtered
AddKeyVal("a", 29, kTypeMerge, test::EncodeInt(2U));
AddKeyVal("a", 28, kTypeMerge, test::EncodeInt(1U));
AddKeyVal("a", 27, kTypeMerge, test::EncodeInt(3U));
AddKeyVal("a", 26, kTypeMerge, test::EncodeInt(5U)); // Filtered
AddKeyVal("a", 25, kTypeMerge, test::EncodeInt(5U)); // Filtered
AddKeyVal("b", 24, kTypeValue, test::EncodeInt(5U)); // next user key
ASSERT_OK(Run(15, true));
ASSERT_TRUE(iter_->Valid());
MergeOutputIterator merge_output_iter(merge_helper_.get());
merge_output_iter.SeekToFirst();
// sequence number is 29 here, because the first merge operand got filtered
// out
ASSERT_EQ(test::KeyStr("a", 29, kTypeValue),
merge_output_iter.key().ToString());
ASSERT_EQ(test::EncodeInt(6U), merge_output_iter.value().ToString());
merge_output_iter.Next();
ASSERT_FALSE(merge_output_iter.Valid());
// make sure that we're passing user keys into the filter
ASSERT_EQ("a", filter_->last_merge_operand_key());
}
// Make sure that merge operands are not filtered out if there's a snapshot
// pointing at them
TEST_F(MergeHelperTest, DontFilterMergeOperandsBeforeSnapshotTest) {
merge_op_ = MergeOperators::CreateUInt64AddOperator();
filter_.reset(new test::FilterNumber(5U));
AddKeyVal("a", 31, kTypeMerge, test::EncodeInt(5U));
AddKeyVal("a", 30, kTypeMerge, test::EncodeInt(5U));
AddKeyVal("a", 29, kTypeMerge, test::EncodeInt(2U));
AddKeyVal("a", 28, kTypeMerge, test::EncodeInt(1U));
AddKeyVal("a", 27, kTypeMerge, test::EncodeInt(3U));
AddKeyVal("a", 26, kTypeMerge, test::EncodeInt(5U));
AddKeyVal("a", 25, kTypeMerge, test::EncodeInt(5U));
AddKeyVal("b", 24, kTypeValue, test::EncodeInt(5U));
ASSERT_OK(Run(15, true, 32));
ASSERT_TRUE(iter_->Valid());
MergeOutputIterator merge_output_iter(merge_helper_.get());
merge_output_iter.SeekToFirst();
ASSERT_EQ(test::KeyStr("a", 31, kTypeValue),
merge_output_iter.key().ToString());
ASSERT_EQ(test::EncodeInt(26U), merge_output_iter.value().ToString());
merge_output_iter.Next();
ASSERT_FALSE(merge_output_iter.Valid());
}
} // namespace ROCKSDB_NAMESPACE
int main(int argc, char** argv) {
ROCKSDB_NAMESPACE::port::InstallStackTraceHandler();
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}