rocksdb/db/write_batch.cc
Yanqin Jin ae152ee666 Avoid user key copying for Get/Put/Write with user-timestamp (#5502)
Summary:
In previous https://github.com/facebook/rocksdb/issues/5079, we added user-specified timestamp to `DB::Get()` and `DB::Put()`. Limitation is that these two functions may cause extra memory allocation and key copy. The reason is that `WriteBatch` does not allocate extra memory for timestamps because it is not aware of timestamp size, and we did not provide an API to assign/update timestamp of each key within a `WriteBatch`.
We address these issues in this PR by doing the following.
1. Add a `timestamp_size_` to `WriteBatch` so that `WriteBatch` can take timestamps into account when calling `WriteBatch::Put`, `WriteBatch::Delete`, etc.
2. Add APIs `WriteBatch::AssignTimestamp` and `WriteBatch::AssignTimestamps` so that application can assign/update timestamps for each key in a `WriteBatch`.
3. Avoid key copy in `GetImpl` by adding new constructor to `LookupKey`.

Test plan (on devserver):
```
$make clean && COMPILE_WITH_ASAN=1 make -j32 all
$./db_basic_test --gtest_filter=Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/*
$make check
```
If the API extension looks good, I will add more unit tests.

Some simple benchmark using db_bench.
```
$rm -rf /dev/shm/dbbench/* && TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=fillseq,readrandom -num=1000000
$rm -rf /dev/shm/dbbench/* && TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=fillrandom -num=1000000 -disable_wal=true
```
Master is at a78503bd6c.
```
|        | readrandom | fillrandom |
| master | 15.53 MB/s | 25.97 MB/s |
| PR5502 | 16.70 MB/s | 25.80 MB/s |
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5502

Differential Revision: D16340894

Pulled By: riversand963

fbshipit-source-id: 51132cf792be07d1efc3ac33f5768c4ee2608bb8
2019-07-25 15:27:39 -07:00

2014 lines
71 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).
//
// 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.
//
// WriteBatch::rep_ :=
// sequence: fixed64
// count: fixed32
// data: record[count]
// record :=
// kTypeValue varstring varstring
// kTypeDeletion varstring
// kTypeSingleDeletion varstring
// kTypeRangeDeletion varstring varstring
// kTypeMerge varstring varstring
// kTypeColumnFamilyValue varint32 varstring varstring
// kTypeColumnFamilyDeletion varint32 varstring
// kTypeColumnFamilySingleDeletion varint32 varstring
// kTypeColumnFamilyRangeDeletion varint32 varstring varstring
// kTypeColumnFamilyMerge varint32 varstring varstring
// kTypeBeginPrepareXID varstring
// kTypeEndPrepareXID
// kTypeCommitXID varstring
// kTypeRollbackXID varstring
// kTypeBeginPersistedPrepareXID varstring
// kTypeBeginUnprepareXID varstring
// kTypeNoop
// varstring :=
// len: varint32
// data: uint8[len]
#include "rocksdb/write_batch.h"
#include <map>
#include <stack>
#include <stdexcept>
#include <type_traits>
#include <vector>
#include "db/column_family.h"
#include "db/db_impl/db_impl.h"
#include "db/dbformat.h"
#include "db/flush_scheduler.h"
#include "db/memtable.h"
#include "db/merge_context.h"
#include "db/snapshot_impl.h"
#include "db/write_batch_internal.h"
#include "monitoring/perf_context_imp.h"
#include "monitoring/statistics.h"
#include "rocksdb/merge_operator.h"
#include "util/autovector.h"
#include "util/coding.h"
#include "util/duplicate_detector.h"
#include "util/string_util.h"
#include "util/util.h"
namespace rocksdb {
// anon namespace for file-local types
namespace {
enum ContentFlags : uint32_t {
DEFERRED = 1 << 0,
HAS_PUT = 1 << 1,
HAS_DELETE = 1 << 2,
HAS_SINGLE_DELETE = 1 << 3,
HAS_MERGE = 1 << 4,
HAS_BEGIN_PREPARE = 1 << 5,
HAS_END_PREPARE = 1 << 6,
HAS_COMMIT = 1 << 7,
HAS_ROLLBACK = 1 << 8,
HAS_DELETE_RANGE = 1 << 9,
HAS_BLOB_INDEX = 1 << 10,
HAS_BEGIN_UNPREPARE = 1 << 11,
};
struct BatchContentClassifier : public WriteBatch::Handler {
uint32_t content_flags = 0;
Status PutCF(uint32_t, const Slice&, const Slice&) override {
content_flags |= ContentFlags::HAS_PUT;
return Status::OK();
}
Status DeleteCF(uint32_t, const Slice&) override {
content_flags |= ContentFlags::HAS_DELETE;
return Status::OK();
}
Status SingleDeleteCF(uint32_t, const Slice&) override {
content_flags |= ContentFlags::HAS_SINGLE_DELETE;
return Status::OK();
}
Status DeleteRangeCF(uint32_t, const Slice&, const Slice&) override {
content_flags |= ContentFlags::HAS_DELETE_RANGE;
return Status::OK();
}
Status MergeCF(uint32_t, const Slice&, const Slice&) override {
content_flags |= ContentFlags::HAS_MERGE;
return Status::OK();
}
Status PutBlobIndexCF(uint32_t, const Slice&, const Slice&) override {
content_flags |= ContentFlags::HAS_BLOB_INDEX;
return Status::OK();
}
Status MarkBeginPrepare(bool unprepare) override {
content_flags |= ContentFlags::HAS_BEGIN_PREPARE;
if (unprepare) {
content_flags |= ContentFlags::HAS_BEGIN_UNPREPARE;
}
return Status::OK();
}
Status MarkEndPrepare(const Slice&) override {
content_flags |= ContentFlags::HAS_END_PREPARE;
return Status::OK();
}
Status MarkCommit(const Slice&) override {
content_flags |= ContentFlags::HAS_COMMIT;
return Status::OK();
}
Status MarkRollback(const Slice&) override {
content_flags |= ContentFlags::HAS_ROLLBACK;
return Status::OK();
}
};
class TimestampAssigner : public WriteBatch::Handler {
public:
explicit TimestampAssigner(const Slice& ts)
: timestamp_(ts), timestamps_(kEmptyTimestampList) {}
explicit TimestampAssigner(const std::vector<Slice>& ts_list)
: timestamps_(ts_list) {
SanityCheck();
}
~TimestampAssigner() override {}
Status PutCF(uint32_t, const Slice& key, const Slice&) override {
AssignTimestamp(key);
++idx_;
return Status::OK();
}
Status DeleteCF(uint32_t, const Slice& key) override {
AssignTimestamp(key);
++idx_;
return Status::OK();
}
Status SingleDeleteCF(uint32_t, const Slice& key) override {
AssignTimestamp(key);
++idx_;
return Status::OK();
}
Status DeleteRangeCF(uint32_t, const Slice& begin_key,
const Slice& end_key) override {
AssignTimestamp(begin_key);
AssignTimestamp(end_key);
++idx_;
return Status::OK();
}
Status MergeCF(uint32_t, const Slice& key, const Slice&) override {
AssignTimestamp(key);
++idx_;
return Status::OK();
}
Status PutBlobIndexCF(uint32_t, const Slice&, const Slice&) override {
// TODO (yanqin): support blob db in the future.
return Status::OK();
}
Status MarkBeginPrepare(bool) override {
// TODO (yanqin): support in the future.
return Status::OK();
}
Status MarkEndPrepare(const Slice&) override {
// TODO (yanqin): support in the future.
return Status::OK();
}
Status MarkCommit(const Slice&) override {
// TODO (yanqin): support in the future.
return Status::OK();
}
Status MarkRollback(const Slice&) override {
// TODO (yanqin): support in the future.
return Status::OK();
}
private:
void SanityCheck() const {
assert(!timestamps_.empty());
#ifndef NDEBUG
const size_t ts_sz = timestamps_[0].size();
for (size_t i = 1; i != timestamps_.size(); ++i) {
assert(ts_sz == timestamps_[i].size());
}
#endif // !NDEBUG
}
void AssignTimestamp(const Slice& key) {
assert(timestamps_.empty() || idx_ < timestamps_.size());
const Slice& ts = timestamps_.empty() ? timestamp_ : timestamps_[idx_];
size_t ts_sz = ts.size();
char* ptr = const_cast<char*>(key.data() + key.size() - ts_sz);
memcpy(ptr, ts.data(), ts_sz);
}
static const std::vector<Slice> kEmptyTimestampList;
const Slice timestamp_;
const std::vector<Slice>& timestamps_;
size_t idx_ = 0;
// No copy or move.
TimestampAssigner(const TimestampAssigner&) = delete;
TimestampAssigner(TimestampAssigner&&) = delete;
TimestampAssigner& operator=(const TimestampAssigner&) = delete;
TimestampAssigner&& operator=(TimestampAssigner&&) = delete;
};
const std::vector<Slice> TimestampAssigner::kEmptyTimestampList;
} // anon namespace
struct SavePoints {
std::stack<SavePoint, autovector<SavePoint>> stack;
};
WriteBatch::WriteBatch(size_t reserved_bytes, size_t max_bytes)
: content_flags_(0), max_bytes_(max_bytes), rep_(), timestamp_size_(0) {
rep_.reserve((reserved_bytes > WriteBatchInternal::kHeader)
? reserved_bytes
: WriteBatchInternal::kHeader);
rep_.resize(WriteBatchInternal::kHeader);
}
WriteBatch::WriteBatch(size_t reserved_bytes, size_t max_bytes, size_t ts_sz)
: content_flags_(0), max_bytes_(max_bytes), rep_(), timestamp_size_(ts_sz) {
rep_.reserve((reserved_bytes > WriteBatchInternal::kHeader) ?
reserved_bytes : WriteBatchInternal::kHeader);
rep_.resize(WriteBatchInternal::kHeader);
}
WriteBatch::WriteBatch(const std::string& rep)
: content_flags_(ContentFlags::DEFERRED),
max_bytes_(0),
rep_(rep),
timestamp_size_(0) {}
WriteBatch::WriteBatch(std::string&& rep)
: content_flags_(ContentFlags::DEFERRED),
max_bytes_(0),
rep_(std::move(rep)),
timestamp_size_(0) {}
WriteBatch::WriteBatch(const WriteBatch& src)
: wal_term_point_(src.wal_term_point_),
content_flags_(src.content_flags_.load(std::memory_order_relaxed)),
max_bytes_(src.max_bytes_),
rep_(src.rep_),
timestamp_size_(src.timestamp_size_) {
if (src.save_points_ != nullptr) {
save_points_.reset(new SavePoints());
save_points_->stack = src.save_points_->stack;
}
}
WriteBatch::WriteBatch(WriteBatch&& src) noexcept
: save_points_(std::move(src.save_points_)),
wal_term_point_(std::move(src.wal_term_point_)),
content_flags_(src.content_flags_.load(std::memory_order_relaxed)),
max_bytes_(src.max_bytes_),
rep_(std::move(src.rep_)),
timestamp_size_(src.timestamp_size_) {}
WriteBatch& WriteBatch::operator=(const WriteBatch& src) {
if (&src != this) {
this->~WriteBatch();
new (this) WriteBatch(src);
}
return *this;
}
WriteBatch& WriteBatch::operator=(WriteBatch&& src) {
if (&src != this) {
this->~WriteBatch();
new (this) WriteBatch(std::move(src));
}
return *this;
}
WriteBatch::~WriteBatch() { }
WriteBatch::Handler::~Handler() { }
void WriteBatch::Handler::LogData(const Slice& /*blob*/) {
// If the user has not specified something to do with blobs, then we ignore
// them.
}
bool WriteBatch::Handler::Continue() {
return true;
}
void WriteBatch::Clear() {
rep_.clear();
rep_.resize(WriteBatchInternal::kHeader);
content_flags_.store(0, std::memory_order_relaxed);
if (save_points_ != nullptr) {
while (!save_points_->stack.empty()) {
save_points_->stack.pop();
}
}
wal_term_point_.clear();
}
int WriteBatch::Count() const {
return WriteBatchInternal::Count(this);
}
uint32_t WriteBatch::ComputeContentFlags() const {
auto rv = content_flags_.load(std::memory_order_relaxed);
if ((rv & ContentFlags::DEFERRED) != 0) {
BatchContentClassifier classifier;
Iterate(&classifier);
rv = classifier.content_flags;
// this method is conceptually const, because it is performing a lazy
// computation that doesn't affect the abstract state of the batch.
// content_flags_ is marked mutable so that we can perform the
// following assignment
content_flags_.store(rv, std::memory_order_relaxed);
}
return rv;
}
void WriteBatch::MarkWalTerminationPoint() {
wal_term_point_.size = GetDataSize();
wal_term_point_.count = Count();
wal_term_point_.content_flags = content_flags_;
}
bool WriteBatch::HasPut() const {
return (ComputeContentFlags() & ContentFlags::HAS_PUT) != 0;
}
bool WriteBatch::HasDelete() const {
return (ComputeContentFlags() & ContentFlags::HAS_DELETE) != 0;
}
bool WriteBatch::HasSingleDelete() const {
return (ComputeContentFlags() & ContentFlags::HAS_SINGLE_DELETE) != 0;
}
bool WriteBatch::HasDeleteRange() const {
return (ComputeContentFlags() & ContentFlags::HAS_DELETE_RANGE) != 0;
}
bool WriteBatch::HasMerge() const {
return (ComputeContentFlags() & ContentFlags::HAS_MERGE) != 0;
}
bool ReadKeyFromWriteBatchEntry(Slice* input, Slice* key, bool cf_record) {
assert(input != nullptr && key != nullptr);
// Skip tag byte
input->remove_prefix(1);
if (cf_record) {
// Skip column_family bytes
uint32_t cf;
if (!GetVarint32(input, &cf)) {
return false;
}
}
// Extract key
return GetLengthPrefixedSlice(input, key);
}
bool WriteBatch::HasBeginPrepare() const {
return (ComputeContentFlags() & ContentFlags::HAS_BEGIN_PREPARE) != 0;
}
bool WriteBatch::HasEndPrepare() const {
return (ComputeContentFlags() & ContentFlags::HAS_END_PREPARE) != 0;
}
bool WriteBatch::HasCommit() const {
return (ComputeContentFlags() & ContentFlags::HAS_COMMIT) != 0;
}
bool WriteBatch::HasRollback() const {
return (ComputeContentFlags() & ContentFlags::HAS_ROLLBACK) != 0;
}
Status ReadRecordFromWriteBatch(Slice* input, char* tag,
uint32_t* column_family, Slice* key,
Slice* value, Slice* blob, Slice* xid) {
assert(key != nullptr && value != nullptr);
*tag = (*input)[0];
input->remove_prefix(1);
*column_family = 0; // default
switch (*tag) {
case kTypeColumnFamilyValue:
if (!GetVarint32(input, column_family)) {
return Status::Corruption("bad WriteBatch Put");
}
FALLTHROUGH_INTENDED;
case kTypeValue:
if (!GetLengthPrefixedSlice(input, key) ||
!GetLengthPrefixedSlice(input, value)) {
return Status::Corruption("bad WriteBatch Put");
}
break;
case kTypeColumnFamilyDeletion:
case kTypeColumnFamilySingleDeletion:
if (!GetVarint32(input, column_family)) {
return Status::Corruption("bad WriteBatch Delete");
}
FALLTHROUGH_INTENDED;
case kTypeDeletion:
case kTypeSingleDeletion:
if (!GetLengthPrefixedSlice(input, key)) {
return Status::Corruption("bad WriteBatch Delete");
}
break;
case kTypeColumnFamilyRangeDeletion:
if (!GetVarint32(input, column_family)) {
return Status::Corruption("bad WriteBatch DeleteRange");
}
FALLTHROUGH_INTENDED;
case kTypeRangeDeletion:
// for range delete, "key" is begin_key, "value" is end_key
if (!GetLengthPrefixedSlice(input, key) ||
!GetLengthPrefixedSlice(input, value)) {
return Status::Corruption("bad WriteBatch DeleteRange");
}
break;
case kTypeColumnFamilyMerge:
if (!GetVarint32(input, column_family)) {
return Status::Corruption("bad WriteBatch Merge");
}
FALLTHROUGH_INTENDED;
case kTypeMerge:
if (!GetLengthPrefixedSlice(input, key) ||
!GetLengthPrefixedSlice(input, value)) {
return Status::Corruption("bad WriteBatch Merge");
}
break;
case kTypeColumnFamilyBlobIndex:
if (!GetVarint32(input, column_family)) {
return Status::Corruption("bad WriteBatch BlobIndex");
}
FALLTHROUGH_INTENDED;
case kTypeBlobIndex:
if (!GetLengthPrefixedSlice(input, key) ||
!GetLengthPrefixedSlice(input, value)) {
return Status::Corruption("bad WriteBatch BlobIndex");
}
break;
case kTypeLogData:
assert(blob != nullptr);
if (!GetLengthPrefixedSlice(input, blob)) {
return Status::Corruption("bad WriteBatch Blob");
}
break;
case kTypeNoop:
case kTypeBeginPrepareXID:
// This indicates that the prepared batch is also persisted in the db.
// This is used in WritePreparedTxn
case kTypeBeginPersistedPrepareXID:
// This is used in WriteUnpreparedTxn
case kTypeBeginUnprepareXID:
break;
case kTypeEndPrepareXID:
if (!GetLengthPrefixedSlice(input, xid)) {
return Status::Corruption("bad EndPrepare XID");
}
break;
case kTypeCommitXID:
if (!GetLengthPrefixedSlice(input, xid)) {
return Status::Corruption("bad Commit XID");
}
break;
case kTypeRollbackXID:
if (!GetLengthPrefixedSlice(input, xid)) {
return Status::Corruption("bad Rollback XID");
}
break;
default:
return Status::Corruption("unknown WriteBatch tag");
}
return Status::OK();
}
Status WriteBatch::Iterate(Handler* handler) const {
Slice input(rep_);
if (input.size() < WriteBatchInternal::kHeader) {
return Status::Corruption("malformed WriteBatch (too small)");
}
input.remove_prefix(WriteBatchInternal::kHeader);
Slice key, value, blob, xid;
// Sometimes a sub-batch starts with a Noop. We want to exclude such Noops as
// the batch boundary symbols otherwise we would mis-count the number of
// batches. We do that by checking whether the accumulated batch is empty
// before seeing the next Noop.
bool empty_batch = true;
int found = 0;
Status s;
char tag = 0;
uint32_t column_family = 0; // default
bool last_was_try_again = false;
bool handler_continue = true;
while (((s.ok() && !input.empty()) || UNLIKELY(s.IsTryAgain()))) {
handler_continue = handler->Continue();
if (!handler_continue) {
break;
}
if (LIKELY(!s.IsTryAgain())) {
last_was_try_again = false;
tag = 0;
column_family = 0; // default
s = ReadRecordFromWriteBatch(&input, &tag, &column_family, &key, &value,
&blob, &xid);
if (!s.ok()) {
return s;
}
} else {
assert(s.IsTryAgain());
assert(!last_was_try_again); // to detect infinite loop bugs
if (UNLIKELY(last_was_try_again)) {
return Status::Corruption(
"two consecutive TryAgain in WriteBatch handler; this is either a "
"software bug or data corruption.");
}
last_was_try_again = true;
s = Status::OK();
}
switch (tag) {
case kTypeColumnFamilyValue:
case kTypeValue:
assert(content_flags_.load(std::memory_order_relaxed) &
(ContentFlags::DEFERRED | ContentFlags::HAS_PUT));
s = handler->PutCF(column_family, key, value);
if (LIKELY(s.ok())) {
empty_batch = false;
found++;
}
break;
case kTypeColumnFamilyDeletion:
case kTypeDeletion:
assert(content_flags_.load(std::memory_order_relaxed) &
(ContentFlags::DEFERRED | ContentFlags::HAS_DELETE));
s = handler->DeleteCF(column_family, key);
if (LIKELY(s.ok())) {
empty_batch = false;
found++;
}
break;
case kTypeColumnFamilySingleDeletion:
case kTypeSingleDeletion:
assert(content_flags_.load(std::memory_order_relaxed) &
(ContentFlags::DEFERRED | ContentFlags::HAS_SINGLE_DELETE));
s = handler->SingleDeleteCF(column_family, key);
if (LIKELY(s.ok())) {
empty_batch = false;
found++;
}
break;
case kTypeColumnFamilyRangeDeletion:
case kTypeRangeDeletion:
assert(content_flags_.load(std::memory_order_relaxed) &
(ContentFlags::DEFERRED | ContentFlags::HAS_DELETE_RANGE));
s = handler->DeleteRangeCF(column_family, key, value);
if (LIKELY(s.ok())) {
empty_batch = false;
found++;
}
break;
case kTypeColumnFamilyMerge:
case kTypeMerge:
assert(content_flags_.load(std::memory_order_relaxed) &
(ContentFlags::DEFERRED | ContentFlags::HAS_MERGE));
s = handler->MergeCF(column_family, key, value);
if (LIKELY(s.ok())) {
empty_batch = false;
found++;
}
break;
case kTypeColumnFamilyBlobIndex:
case kTypeBlobIndex:
assert(content_flags_.load(std::memory_order_relaxed) &
(ContentFlags::DEFERRED | ContentFlags::HAS_BLOB_INDEX));
s = handler->PutBlobIndexCF(column_family, key, value);
if (LIKELY(s.ok())) {
found++;
}
break;
case kTypeLogData:
handler->LogData(blob);
// A batch might have nothing but LogData. It is still a batch.
empty_batch = false;
break;
case kTypeBeginPrepareXID:
assert(content_flags_.load(std::memory_order_relaxed) &
(ContentFlags::DEFERRED | ContentFlags::HAS_BEGIN_PREPARE));
handler->MarkBeginPrepare();
empty_batch = false;
if (!handler->WriteAfterCommit()) {
s = Status::NotSupported(
"WriteCommitted txn tag when write_after_commit_ is disabled (in "
"WritePrepared/WriteUnprepared mode). If it is not due to "
"corruption, the WAL must be emptied before changing the "
"WritePolicy.");
}
if (handler->WriteBeforePrepare()) {
s = Status::NotSupported(
"WriteCommitted txn tag when write_before_prepare_ is enabled "
"(in WriteUnprepared mode). If it is not due to corruption, the "
"WAL must be emptied before changing the WritePolicy.");
}
break;
case kTypeBeginPersistedPrepareXID:
assert(content_flags_.load(std::memory_order_relaxed) &
(ContentFlags::DEFERRED | ContentFlags::HAS_BEGIN_PREPARE));
handler->MarkBeginPrepare();
empty_batch = false;
if (handler->WriteAfterCommit()) {
s = Status::NotSupported(
"WritePrepared/WriteUnprepared txn tag when write_after_commit_ "
"is enabled (in default WriteCommitted mode). If it is not due "
"to corruption, the WAL must be emptied before changing the "
"WritePolicy.");
}
break;
case kTypeBeginUnprepareXID:
assert(content_flags_.load(std::memory_order_relaxed) &
(ContentFlags::DEFERRED | ContentFlags::HAS_BEGIN_UNPREPARE));
handler->MarkBeginPrepare(true /* unprepared */);
empty_batch = false;
if (handler->WriteAfterCommit()) {
s = Status::NotSupported(
"WriteUnprepared txn tag when write_after_commit_ is enabled (in "
"default WriteCommitted mode). If it is not due to corruption, "
"the WAL must be emptied before changing the WritePolicy.");
}
if (!handler->WriteBeforePrepare()) {
s = Status::NotSupported(
"WriteUnprepared txn tag when write_before_prepare_ is disabled "
"(in WriteCommitted/WritePrepared mode). If it is not due to "
"corruption, the WAL must be emptied before changing the "
"WritePolicy.");
}
break;
case kTypeEndPrepareXID:
assert(content_flags_.load(std::memory_order_relaxed) &
(ContentFlags::DEFERRED | ContentFlags::HAS_END_PREPARE));
handler->MarkEndPrepare(xid);
empty_batch = true;
break;
case kTypeCommitXID:
assert(content_flags_.load(std::memory_order_relaxed) &
(ContentFlags::DEFERRED | ContentFlags::HAS_COMMIT));
handler->MarkCommit(xid);
empty_batch = true;
break;
case kTypeRollbackXID:
assert(content_flags_.load(std::memory_order_relaxed) &
(ContentFlags::DEFERRED | ContentFlags::HAS_ROLLBACK));
handler->MarkRollback(xid);
empty_batch = true;
break;
case kTypeNoop:
handler->MarkNoop(empty_batch);
empty_batch = true;
break;
default:
return Status::Corruption("unknown WriteBatch tag");
}
}
if (!s.ok()) {
return s;
}
if (handler_continue && found != WriteBatchInternal::Count(this)) {
return Status::Corruption("WriteBatch has wrong count");
} else {
return Status::OK();
}
}
bool WriteBatchInternal::IsLatestPersistentState(const WriteBatch* b) {
return b->is_latest_persistent_state_;
}
void WriteBatchInternal::SetAsLastestPersistentState(WriteBatch* b) {
b->is_latest_persistent_state_ = true;
}
int WriteBatchInternal::Count(const WriteBatch* b) {
return DecodeFixed32(b->rep_.data() + 8);
}
void WriteBatchInternal::SetCount(WriteBatch* b, int n) {
EncodeFixed32(&b->rep_[8], n);
}
SequenceNumber WriteBatchInternal::Sequence(const WriteBatch* b) {
return SequenceNumber(DecodeFixed64(b->rep_.data()));
}
void WriteBatchInternal::SetSequence(WriteBatch* b, SequenceNumber seq) {
EncodeFixed64(&b->rep_[0], seq);
}
size_t WriteBatchInternal::GetFirstOffset(WriteBatch* /*b*/) {
return WriteBatchInternal::kHeader;
}
Status WriteBatchInternal::Put(WriteBatch* b, uint32_t column_family_id,
const Slice& key, const Slice& value) {
if (key.size() > size_t{port::kMaxUint32}) {
return Status::InvalidArgument("key is too large");
}
if (value.size() > size_t{port::kMaxUint32}) {
return Status::InvalidArgument("value is too large");
}
LocalSavePoint save(b);
WriteBatchInternal::SetCount(b, WriteBatchInternal::Count(b) + 1);
if (column_family_id == 0) {
b->rep_.push_back(static_cast<char>(kTypeValue));
} else {
b->rep_.push_back(static_cast<char>(kTypeColumnFamilyValue));
PutVarint32(&b->rep_, column_family_id);
}
if (0 == b->timestamp_size_) {
PutLengthPrefixedSlice(&b->rep_, key);
} else {
PutVarint32(&b->rep_,
static_cast<uint32_t>(key.size() + b->timestamp_size_));
b->rep_.append(key.data(), key.size());
b->rep_.append(b->timestamp_size_, '\0');
}
PutLengthPrefixedSlice(&b->rep_, value);
b->content_flags_.store(
b->content_flags_.load(std::memory_order_relaxed) | ContentFlags::HAS_PUT,
std::memory_order_relaxed);
return save.commit();
}
Status WriteBatch::Put(ColumnFamilyHandle* column_family, const Slice& key,
const Slice& value) {
return WriteBatchInternal::Put(this, GetColumnFamilyID(column_family), key,
value);
}
Status WriteBatchInternal::CheckSlicePartsLength(const SliceParts& key,
const SliceParts& value) {
size_t total_key_bytes = 0;
for (int i = 0; i < key.num_parts; ++i) {
total_key_bytes += key.parts[i].size();
}
if (total_key_bytes >= size_t{port::kMaxUint32}) {
return Status::InvalidArgument("key is too large");
}
size_t total_value_bytes = 0;
for (int i = 0; i < value.num_parts; ++i) {
total_value_bytes += value.parts[i].size();
}
if (total_value_bytes >= size_t{port::kMaxUint32}) {
return Status::InvalidArgument("value is too large");
}
return Status::OK();
}
Status WriteBatchInternal::Put(WriteBatch* b, uint32_t column_family_id,
const SliceParts& key, const SliceParts& value) {
Status s = CheckSlicePartsLength(key, value);
if (!s.ok()) {
return s;
}
LocalSavePoint save(b);
WriteBatchInternal::SetCount(b, WriteBatchInternal::Count(b) + 1);
if (column_family_id == 0) {
b->rep_.push_back(static_cast<char>(kTypeValue));
} else {
b->rep_.push_back(static_cast<char>(kTypeColumnFamilyValue));
PutVarint32(&b->rep_, column_family_id);
}
if (0 == b->timestamp_size_) {
PutLengthPrefixedSliceParts(&b->rep_, key);
} else {
PutLengthPrefixedSlicePartsWithPadding(&b->rep_, key, b->timestamp_size_);
}
PutLengthPrefixedSliceParts(&b->rep_, value);
b->content_flags_.store(
b->content_flags_.load(std::memory_order_relaxed) | ContentFlags::HAS_PUT,
std::memory_order_relaxed);
return save.commit();
}
Status WriteBatch::Put(ColumnFamilyHandle* column_family, const SliceParts& key,
const SliceParts& value) {
return WriteBatchInternal::Put(this, GetColumnFamilyID(column_family), key,
value);
}
Status WriteBatchInternal::InsertNoop(WriteBatch* b) {
b->rep_.push_back(static_cast<char>(kTypeNoop));
return Status::OK();
}
Status WriteBatchInternal::MarkEndPrepare(WriteBatch* b, const Slice& xid,
bool write_after_commit,
bool unprepared_batch) {
// a manually constructed batch can only contain one prepare section
assert(b->rep_[12] == static_cast<char>(kTypeNoop));
// all savepoints up to this point are cleared
if (b->save_points_ != nullptr) {
while (!b->save_points_->stack.empty()) {
b->save_points_->stack.pop();
}
}
// rewrite noop as begin marker
b->rep_[12] = static_cast<char>(
write_after_commit ? kTypeBeginPrepareXID
: (unprepared_batch ? kTypeBeginUnprepareXID
: kTypeBeginPersistedPrepareXID));
b->rep_.push_back(static_cast<char>(kTypeEndPrepareXID));
PutLengthPrefixedSlice(&b->rep_, xid);
b->content_flags_.store(b->content_flags_.load(std::memory_order_relaxed) |
ContentFlags::HAS_END_PREPARE |
ContentFlags::HAS_BEGIN_PREPARE,
std::memory_order_relaxed);
if (unprepared_batch) {
b->content_flags_.store(b->content_flags_.load(std::memory_order_relaxed) |
ContentFlags::HAS_BEGIN_UNPREPARE,
std::memory_order_relaxed);
}
return Status::OK();
}
Status WriteBatchInternal::MarkCommit(WriteBatch* b, const Slice& xid) {
b->rep_.push_back(static_cast<char>(kTypeCommitXID));
PutLengthPrefixedSlice(&b->rep_, xid);
b->content_flags_.store(b->content_flags_.load(std::memory_order_relaxed) |
ContentFlags::HAS_COMMIT,
std::memory_order_relaxed);
return Status::OK();
}
Status WriteBatchInternal::MarkRollback(WriteBatch* b, const Slice& xid) {
b->rep_.push_back(static_cast<char>(kTypeRollbackXID));
PutLengthPrefixedSlice(&b->rep_, xid);
b->content_flags_.store(b->content_flags_.load(std::memory_order_relaxed) |
ContentFlags::HAS_ROLLBACK,
std::memory_order_relaxed);
return Status::OK();
}
Status WriteBatchInternal::Delete(WriteBatch* b, uint32_t column_family_id,
const Slice& key) {
LocalSavePoint save(b);
WriteBatchInternal::SetCount(b, WriteBatchInternal::Count(b) + 1);
if (column_family_id == 0) {
b->rep_.push_back(static_cast<char>(kTypeDeletion));
} else {
b->rep_.push_back(static_cast<char>(kTypeColumnFamilyDeletion));
PutVarint32(&b->rep_, column_family_id);
}
PutLengthPrefixedSlice(&b->rep_, key);
b->content_flags_.store(b->content_flags_.load(std::memory_order_relaxed) |
ContentFlags::HAS_DELETE,
std::memory_order_relaxed);
return save.commit();
}
Status WriteBatch::Delete(ColumnFamilyHandle* column_family, const Slice& key) {
return WriteBatchInternal::Delete(this, GetColumnFamilyID(column_family),
key);
}
Status WriteBatchInternal::Delete(WriteBatch* b, uint32_t column_family_id,
const SliceParts& key) {
LocalSavePoint save(b);
WriteBatchInternal::SetCount(b, WriteBatchInternal::Count(b) + 1);
if (column_family_id == 0) {
b->rep_.push_back(static_cast<char>(kTypeDeletion));
} else {
b->rep_.push_back(static_cast<char>(kTypeColumnFamilyDeletion));
PutVarint32(&b->rep_, column_family_id);
}
PutLengthPrefixedSliceParts(&b->rep_, key);
b->content_flags_.store(b->content_flags_.load(std::memory_order_relaxed) |
ContentFlags::HAS_DELETE,
std::memory_order_relaxed);
return save.commit();
}
Status WriteBatch::Delete(ColumnFamilyHandle* column_family,
const SliceParts& key) {
return WriteBatchInternal::Delete(this, GetColumnFamilyID(column_family),
key);
}
Status WriteBatchInternal::SingleDelete(WriteBatch* b,
uint32_t column_family_id,
const Slice& key) {
LocalSavePoint save(b);
WriteBatchInternal::SetCount(b, WriteBatchInternal::Count(b) + 1);
if (column_family_id == 0) {
b->rep_.push_back(static_cast<char>(kTypeSingleDeletion));
} else {
b->rep_.push_back(static_cast<char>(kTypeColumnFamilySingleDeletion));
PutVarint32(&b->rep_, column_family_id);
}
PutLengthPrefixedSlice(&b->rep_, key);
b->content_flags_.store(b->content_flags_.load(std::memory_order_relaxed) |
ContentFlags::HAS_SINGLE_DELETE,
std::memory_order_relaxed);
return save.commit();
}
Status WriteBatch::SingleDelete(ColumnFamilyHandle* column_family,
const Slice& key) {
return WriteBatchInternal::SingleDelete(
this, GetColumnFamilyID(column_family), key);
}
Status WriteBatchInternal::SingleDelete(WriteBatch* b,
uint32_t column_family_id,
const SliceParts& key) {
LocalSavePoint save(b);
WriteBatchInternal::SetCount(b, WriteBatchInternal::Count(b) + 1);
if (column_family_id == 0) {
b->rep_.push_back(static_cast<char>(kTypeSingleDeletion));
} else {
b->rep_.push_back(static_cast<char>(kTypeColumnFamilySingleDeletion));
PutVarint32(&b->rep_, column_family_id);
}
PutLengthPrefixedSliceParts(&b->rep_, key);
b->content_flags_.store(b->content_flags_.load(std::memory_order_relaxed) |
ContentFlags::HAS_SINGLE_DELETE,
std::memory_order_relaxed);
return save.commit();
}
Status WriteBatch::SingleDelete(ColumnFamilyHandle* column_family,
const SliceParts& key) {
return WriteBatchInternal::SingleDelete(
this, GetColumnFamilyID(column_family), key);
}
Status WriteBatchInternal::DeleteRange(WriteBatch* b, uint32_t column_family_id,
const Slice& begin_key,
const Slice& end_key) {
LocalSavePoint save(b);
WriteBatchInternal::SetCount(b, WriteBatchInternal::Count(b) + 1);
if (column_family_id == 0) {
b->rep_.push_back(static_cast<char>(kTypeRangeDeletion));
} else {
b->rep_.push_back(static_cast<char>(kTypeColumnFamilyRangeDeletion));
PutVarint32(&b->rep_, column_family_id);
}
PutLengthPrefixedSlice(&b->rep_, begin_key);
PutLengthPrefixedSlice(&b->rep_, end_key);
b->content_flags_.store(b->content_flags_.load(std::memory_order_relaxed) |
ContentFlags::HAS_DELETE_RANGE,
std::memory_order_relaxed);
return save.commit();
}
Status WriteBatch::DeleteRange(ColumnFamilyHandle* column_family,
const Slice& begin_key, const Slice& end_key) {
return WriteBatchInternal::DeleteRange(this, GetColumnFamilyID(column_family),
begin_key, end_key);
}
Status WriteBatchInternal::DeleteRange(WriteBatch* b, uint32_t column_family_id,
const SliceParts& begin_key,
const SliceParts& end_key) {
LocalSavePoint save(b);
WriteBatchInternal::SetCount(b, WriteBatchInternal::Count(b) + 1);
if (column_family_id == 0) {
b->rep_.push_back(static_cast<char>(kTypeRangeDeletion));
} else {
b->rep_.push_back(static_cast<char>(kTypeColumnFamilyRangeDeletion));
PutVarint32(&b->rep_, column_family_id);
}
PutLengthPrefixedSliceParts(&b->rep_, begin_key);
PutLengthPrefixedSliceParts(&b->rep_, end_key);
b->content_flags_.store(b->content_flags_.load(std::memory_order_relaxed) |
ContentFlags::HAS_DELETE_RANGE,
std::memory_order_relaxed);
return save.commit();
}
Status WriteBatch::DeleteRange(ColumnFamilyHandle* column_family,
const SliceParts& begin_key,
const SliceParts& end_key) {
return WriteBatchInternal::DeleteRange(this, GetColumnFamilyID(column_family),
begin_key, end_key);
}
Status WriteBatchInternal::Merge(WriteBatch* b, uint32_t column_family_id,
const Slice& key, const Slice& value) {
if (key.size() > size_t{port::kMaxUint32}) {
return Status::InvalidArgument("key is too large");
}
if (value.size() > size_t{port::kMaxUint32}) {
return Status::InvalidArgument("value is too large");
}
LocalSavePoint save(b);
WriteBatchInternal::SetCount(b, WriteBatchInternal::Count(b) + 1);
if (column_family_id == 0) {
b->rep_.push_back(static_cast<char>(kTypeMerge));
} else {
b->rep_.push_back(static_cast<char>(kTypeColumnFamilyMerge));
PutVarint32(&b->rep_, column_family_id);
}
PutLengthPrefixedSlice(&b->rep_, key);
PutLengthPrefixedSlice(&b->rep_, value);
b->content_flags_.store(b->content_flags_.load(std::memory_order_relaxed) |
ContentFlags::HAS_MERGE,
std::memory_order_relaxed);
return save.commit();
}
Status WriteBatch::Merge(ColumnFamilyHandle* column_family, const Slice& key,
const Slice& value) {
return WriteBatchInternal::Merge(this, GetColumnFamilyID(column_family), key,
value);
}
Status WriteBatchInternal::Merge(WriteBatch* b, uint32_t column_family_id,
const SliceParts& key,
const SliceParts& value) {
Status s = CheckSlicePartsLength(key, value);
if (!s.ok()) {
return s;
}
LocalSavePoint save(b);
WriteBatchInternal::SetCount(b, WriteBatchInternal::Count(b) + 1);
if (column_family_id == 0) {
b->rep_.push_back(static_cast<char>(kTypeMerge));
} else {
b->rep_.push_back(static_cast<char>(kTypeColumnFamilyMerge));
PutVarint32(&b->rep_, column_family_id);
}
PutLengthPrefixedSliceParts(&b->rep_, key);
PutLengthPrefixedSliceParts(&b->rep_, value);
b->content_flags_.store(b->content_flags_.load(std::memory_order_relaxed) |
ContentFlags::HAS_MERGE,
std::memory_order_relaxed);
return save.commit();
}
Status WriteBatch::Merge(ColumnFamilyHandle* column_family,
const SliceParts& key, const SliceParts& value) {
return WriteBatchInternal::Merge(this, GetColumnFamilyID(column_family), key,
value);
}
Status WriteBatchInternal::PutBlobIndex(WriteBatch* b,
uint32_t column_family_id,
const Slice& key, const Slice& value) {
LocalSavePoint save(b);
WriteBatchInternal::SetCount(b, WriteBatchInternal::Count(b) + 1);
if (column_family_id == 0) {
b->rep_.push_back(static_cast<char>(kTypeBlobIndex));
} else {
b->rep_.push_back(static_cast<char>(kTypeColumnFamilyBlobIndex));
PutVarint32(&b->rep_, column_family_id);
}
PutLengthPrefixedSlice(&b->rep_, key);
PutLengthPrefixedSlice(&b->rep_, value);
b->content_flags_.store(b->content_flags_.load(std::memory_order_relaxed) |
ContentFlags::HAS_BLOB_INDEX,
std::memory_order_relaxed);
return save.commit();
}
Status WriteBatch::PutLogData(const Slice& blob) {
LocalSavePoint save(this);
rep_.push_back(static_cast<char>(kTypeLogData));
PutLengthPrefixedSlice(&rep_, blob);
return save.commit();
}
void WriteBatch::SetSavePoint() {
if (save_points_ == nullptr) {
save_points_.reset(new SavePoints());
}
// Record length and count of current batch of writes.
save_points_->stack.push(SavePoint(
GetDataSize(), Count(), content_flags_.load(std::memory_order_relaxed)));
}
Status WriteBatch::RollbackToSavePoint() {
if (save_points_ == nullptr || save_points_->stack.size() == 0) {
return Status::NotFound();
}
// Pop the most recent savepoint off the stack
SavePoint savepoint = save_points_->stack.top();
save_points_->stack.pop();
assert(savepoint.size <= rep_.size());
assert(savepoint.count <= Count());
if (savepoint.size == rep_.size()) {
// No changes to rollback
} else if (savepoint.size == 0) {
// Rollback everything
Clear();
} else {
rep_.resize(savepoint.size);
WriteBatchInternal::SetCount(this, savepoint.count);
content_flags_.store(savepoint.content_flags, std::memory_order_relaxed);
}
return Status::OK();
}
Status WriteBatch::PopSavePoint() {
if (save_points_ == nullptr || save_points_->stack.size() == 0) {
return Status::NotFound();
}
// Pop the most recent savepoint off the stack
save_points_->stack.pop();
return Status::OK();
}
Status WriteBatch::AssignTimestamp(const Slice& ts) {
TimestampAssigner ts_assigner(ts);
return Iterate(&ts_assigner);
}
Status WriteBatch::AssignTimestamps(const std::vector<Slice>& ts_list) {
TimestampAssigner ts_assigner(ts_list);
return Iterate(&ts_assigner);
}
class MemTableInserter : public WriteBatch::Handler {
SequenceNumber sequence_;
ColumnFamilyMemTables* const cf_mems_;
FlushScheduler* const flush_scheduler_;
const bool ignore_missing_column_families_;
const uint64_t recovering_log_number_;
// log number that all Memtables inserted into should reference
uint64_t log_number_ref_;
DBImpl* db_;
const bool concurrent_memtable_writes_;
bool post_info_created_;
bool* has_valid_writes_;
// On some (!) platforms just default creating
// a map is too expensive in the Write() path as they
// cause memory allocations though unused.
// Make creation optional but do not incur
// std::unique_ptr additional allocation
using MemPostInfoMap = std::map<MemTable*, MemTablePostProcessInfo>;
using PostMapType = std::aligned_storage<sizeof(MemPostInfoMap)>::type;
PostMapType mem_post_info_map_;
// current recovered transaction we are rebuilding (recovery)
WriteBatch* rebuilding_trx_;
SequenceNumber rebuilding_trx_seq_;
// Increase seq number once per each write batch. Otherwise increase it once
// per key.
bool seq_per_batch_;
// Whether the memtable write will be done only after the commit
bool write_after_commit_;
// Whether memtable write can be done before prepare
bool write_before_prepare_;
// Whether this batch was unprepared or not
bool unprepared_batch_;
using DupDetector = std::aligned_storage<sizeof(DuplicateDetector)>::type;
DupDetector duplicate_detector_;
bool dup_dectector_on_;
MemPostInfoMap& GetPostMap() {
assert(concurrent_memtable_writes_);
if(!post_info_created_) {
new (&mem_post_info_map_) MemPostInfoMap();
post_info_created_ = true;
}
return *reinterpret_cast<MemPostInfoMap*>(&mem_post_info_map_);
}
bool IsDuplicateKeySeq(uint32_t column_family_id, const Slice& key) {
assert(!write_after_commit_);
assert(rebuilding_trx_ != nullptr);
if (!dup_dectector_on_) {
new (&duplicate_detector_) DuplicateDetector(db_);
dup_dectector_on_ = true;
}
return reinterpret_cast<DuplicateDetector*>
(&duplicate_detector_)->IsDuplicateKeySeq(column_family_id, key, sequence_);
}
protected:
bool WriteBeforePrepare() const override { return write_before_prepare_; }
bool WriteAfterCommit() const override { return write_after_commit_; }
public:
// cf_mems should not be shared with concurrent inserters
MemTableInserter(SequenceNumber _sequence, ColumnFamilyMemTables* cf_mems,
FlushScheduler* flush_scheduler,
bool ignore_missing_column_families,
uint64_t recovering_log_number, DB* db,
bool concurrent_memtable_writes,
bool* has_valid_writes = nullptr, bool seq_per_batch = false,
bool batch_per_txn = true)
: sequence_(_sequence),
cf_mems_(cf_mems),
flush_scheduler_(flush_scheduler),
ignore_missing_column_families_(ignore_missing_column_families),
recovering_log_number_(recovering_log_number),
log_number_ref_(0),
db_(reinterpret_cast<DBImpl*>(db)),
concurrent_memtable_writes_(concurrent_memtable_writes),
post_info_created_(false),
has_valid_writes_(has_valid_writes),
rebuilding_trx_(nullptr),
rebuilding_trx_seq_(0),
seq_per_batch_(seq_per_batch),
// Write after commit currently uses one seq per key (instead of per
// batch). So seq_per_batch being false indicates write_after_commit
// approach.
write_after_commit_(!seq_per_batch),
// WriteUnprepared can write WriteBatches per transaction, so
// batch_per_txn being false indicates write_before_prepare.
write_before_prepare_(!batch_per_txn),
unprepared_batch_(false),
duplicate_detector_(),
dup_dectector_on_(false) {
assert(cf_mems_);
}
~MemTableInserter() override {
if (dup_dectector_on_) {
reinterpret_cast<DuplicateDetector*>
(&duplicate_detector_)->~DuplicateDetector();
}
if (post_info_created_) {
reinterpret_cast<MemPostInfoMap*>
(&mem_post_info_map_)->~MemPostInfoMap();
}
delete rebuilding_trx_;
}
MemTableInserter(const MemTableInserter&) = delete;
MemTableInserter& operator=(const MemTableInserter&) = delete;
// The batch seq is regularly restarted; In normal mode it is set when
// MemTableInserter is constructed in the write thread and in recovery mode it
// is set when a batch, which is tagged with seq, is read from the WAL.
// Within a sequenced batch, which could be a merge of multiple batches, we
// have two policies to advance the seq: i) seq_per_key (default) and ii)
// seq_per_batch. To implement the latter we need to mark the boundary between
// the individual batches. The approach is this: 1) Use the terminating
// markers to indicate the boundary (kTypeEndPrepareXID, kTypeCommitXID,
// kTypeRollbackXID) 2) Terminate a batch with kTypeNoop in the absence of a
// natural boundary marker.
void MaybeAdvanceSeq(bool batch_boundry = false) {
if (batch_boundry == seq_per_batch_) {
sequence_++;
}
}
void set_log_number_ref(uint64_t log) { log_number_ref_ = log; }
SequenceNumber sequence() const { return sequence_; }
void PostProcess() {
assert(concurrent_memtable_writes_);
// If post info was not created there is nothing
// to process and no need to create on demand
if(post_info_created_) {
for (auto& pair : GetPostMap()) {
pair.first->BatchPostProcess(pair.second);
}
}
}
bool SeekToColumnFamily(uint32_t column_family_id, Status* s) {
// If we are in a concurrent mode, it is the caller's responsibility
// to clone the original ColumnFamilyMemTables so that each thread
// has its own instance. Otherwise, it must be guaranteed that there
// is no concurrent access
bool found = cf_mems_->Seek(column_family_id);
if (!found) {
if (ignore_missing_column_families_) {
*s = Status::OK();
} else {
*s = Status::InvalidArgument(
"Invalid column family specified in write batch");
}
return false;
}
if (recovering_log_number_ != 0 &&
recovering_log_number_ < cf_mems_->GetLogNumber()) {
// This is true only in recovery environment (recovering_log_number_ is
// always 0 in
// non-recovery, regular write code-path)
// * If recovering_log_number_ < cf_mems_->GetLogNumber(), this means that
// column
// family already contains updates from this log. We can't apply updates
// twice because of update-in-place or merge workloads -- ignore the
// update
*s = Status::OK();
return false;
}
if (has_valid_writes_ != nullptr) {
*has_valid_writes_ = true;
}
if (log_number_ref_ > 0) {
cf_mems_->GetMemTable()->RefLogContainingPrepSection(log_number_ref_);
}
return true;
}
Status PutCFImpl(uint32_t column_family_id, const Slice& key,
const Slice& value, ValueType value_type) {
// optimize for non-recovery mode
if (UNLIKELY(write_after_commit_ && rebuilding_trx_ != nullptr)) {
WriteBatchInternal::Put(rebuilding_trx_, column_family_id, key, value);
return Status::OK();
// else insert the values to the memtable right away
}
Status seek_status;
if (UNLIKELY(!SeekToColumnFamily(column_family_id, &seek_status))) {
bool batch_boundry = false;
if (rebuilding_trx_ != nullptr) {
assert(!write_after_commit_);
// The CF is probably flushed and hence no need for insert but we still
// need to keep track of the keys for upcoming rollback/commit.
WriteBatchInternal::Put(rebuilding_trx_, column_family_id, key, value);
batch_boundry = IsDuplicateKeySeq(column_family_id, key);
}
MaybeAdvanceSeq(batch_boundry);
return seek_status;
}
Status ret_status;
MemTable* mem = cf_mems_->GetMemTable();
auto* moptions = mem->GetImmutableMemTableOptions();
// inplace_update_support is inconsistent with snapshots, and therefore with
// any kind of transactions including the ones that use seq_per_batch
assert(!seq_per_batch_ || !moptions->inplace_update_support);
if (!moptions->inplace_update_support) {
bool mem_res =
mem->Add(sequence_, value_type, key, value,
concurrent_memtable_writes_, get_post_process_info(mem));
if (UNLIKELY(!mem_res)) {
assert(seq_per_batch_);
ret_status = Status::TryAgain("key+seq exists");
const bool BATCH_BOUNDRY = true;
MaybeAdvanceSeq(BATCH_BOUNDRY);
}
} else if (moptions->inplace_callback == nullptr) {
assert(!concurrent_memtable_writes_);
mem->Update(sequence_, key, value);
} else {
assert(!concurrent_memtable_writes_);
if (mem->UpdateCallback(sequence_, key, value)) {
} else {
// key not found in memtable. Do sst get, update, add
SnapshotImpl read_from_snapshot;
read_from_snapshot.number_ = sequence_;
ReadOptions ropts;
// it's going to be overwritten for sure, so no point caching data block
// containing the old version
ropts.fill_cache = false;
ropts.snapshot = &read_from_snapshot;
std::string prev_value;
std::string merged_value;
auto cf_handle = cf_mems_->GetColumnFamilyHandle();
Status s = Status::NotSupported();
if (db_ != nullptr && recovering_log_number_ == 0) {
if (cf_handle == nullptr) {
cf_handle = db_->DefaultColumnFamily();
}
s = db_->Get(ropts, cf_handle, key, &prev_value);
}
char* prev_buffer = const_cast<char*>(prev_value.c_str());
uint32_t prev_size = static_cast<uint32_t>(prev_value.size());
auto status = moptions->inplace_callback(s.ok() ? prev_buffer : nullptr,
s.ok() ? &prev_size : nullptr,
value, &merged_value);
if (status == UpdateStatus::UPDATED_INPLACE) {
// prev_value is updated in-place with final value.
bool mem_res __attribute__((__unused__));
mem_res = mem->Add(
sequence_, value_type, key, Slice(prev_buffer, prev_size));
assert(mem_res);
RecordTick(moptions->statistics, NUMBER_KEYS_WRITTEN);
} else if (status == UpdateStatus::UPDATED) {
// merged_value contains the final value.
bool mem_res __attribute__((__unused__));
mem_res =
mem->Add(sequence_, value_type, key, Slice(merged_value));
assert(mem_res);
RecordTick(moptions->statistics, NUMBER_KEYS_WRITTEN);
}
}
}
// optimize for non-recovery mode
if (UNLIKELY(!ret_status.IsTryAgain() && rebuilding_trx_ != nullptr)) {
assert(!write_after_commit_);
// If the ret_status is TryAgain then let the next try to add the ky to
// the rebuilding transaction object.
WriteBatchInternal::Put(rebuilding_trx_, column_family_id, key, value);
}
// Since all Puts are logged in transaction logs (if enabled), always bump
// sequence number. Even if the update eventually fails and does not result
// in memtable add/update.
MaybeAdvanceSeq();
CheckMemtableFull();
return ret_status;
}
Status PutCF(uint32_t column_family_id, const Slice& key,
const Slice& value) override {
return PutCFImpl(column_family_id, key, value, kTypeValue);
}
Status DeleteImpl(uint32_t /*column_family_id*/, const Slice& key,
const Slice& value, ValueType delete_type) {
Status ret_status;
MemTable* mem = cf_mems_->GetMemTable();
bool mem_res =
mem->Add(sequence_, delete_type, key, value,
concurrent_memtable_writes_, get_post_process_info(mem));
if (UNLIKELY(!mem_res)) {
assert(seq_per_batch_);
ret_status = Status::TryAgain("key+seq exists");
const bool BATCH_BOUNDRY = true;
MaybeAdvanceSeq(BATCH_BOUNDRY);
}
MaybeAdvanceSeq();
CheckMemtableFull();
return ret_status;
}
Status DeleteCF(uint32_t column_family_id, const Slice& key) override {
// optimize for non-recovery mode
if (UNLIKELY(write_after_commit_ && rebuilding_trx_ != nullptr)) {
WriteBatchInternal::Delete(rebuilding_trx_, column_family_id, key);
return Status::OK();
// else insert the values to the memtable right away
}
Status seek_status;
if (UNLIKELY(!SeekToColumnFamily(column_family_id, &seek_status))) {
bool batch_boundry = false;
if (rebuilding_trx_ != nullptr) {
assert(!write_after_commit_);
// The CF is probably flushed and hence no need for insert but we still
// need to keep track of the keys for upcoming rollback/commit.
WriteBatchInternal::Delete(rebuilding_trx_, column_family_id, key);
batch_boundry = IsDuplicateKeySeq(column_family_id, key);
}
MaybeAdvanceSeq(batch_boundry);
return seek_status;
}
auto ret_status = DeleteImpl(column_family_id, key, Slice(), kTypeDeletion);
// optimize for non-recovery mode
if (UNLIKELY(!ret_status.IsTryAgain() && rebuilding_trx_ != nullptr)) {
assert(!write_after_commit_);
// If the ret_status is TryAgain then let the next try to add the ky to
// the rebuilding transaction object.
WriteBatchInternal::Delete(rebuilding_trx_, column_family_id, key);
}
return ret_status;
}
Status SingleDeleteCF(uint32_t column_family_id, const Slice& key) override {
// optimize for non-recovery mode
if (UNLIKELY(write_after_commit_ && rebuilding_trx_ != nullptr)) {
WriteBatchInternal::SingleDelete(rebuilding_trx_, column_family_id, key);
return Status::OK();
// else insert the values to the memtable right away
}
Status seek_status;
if (UNLIKELY(!SeekToColumnFamily(column_family_id, &seek_status))) {
bool batch_boundry = false;
if (rebuilding_trx_ != nullptr) {
assert(!write_after_commit_);
// The CF is probably flushed and hence no need for insert but we still
// need to keep track of the keys for upcoming rollback/commit.
WriteBatchInternal::SingleDelete(rebuilding_trx_, column_family_id,
key);
batch_boundry = IsDuplicateKeySeq(column_family_id, key);
}
MaybeAdvanceSeq(batch_boundry);
return seek_status;
}
auto ret_status =
DeleteImpl(column_family_id, key, Slice(), kTypeSingleDeletion);
// optimize for non-recovery mode
if (UNLIKELY(!ret_status.IsTryAgain() && rebuilding_trx_ != nullptr)) {
assert(!write_after_commit_);
// If the ret_status is TryAgain then let the next try to add the ky to
// the rebuilding transaction object.
WriteBatchInternal::SingleDelete(rebuilding_trx_, column_family_id, key);
}
return ret_status;
}
Status DeleteRangeCF(uint32_t column_family_id, const Slice& begin_key,
const Slice& end_key) override {
// optimize for non-recovery mode
if (UNLIKELY(write_after_commit_ && rebuilding_trx_ != nullptr)) {
WriteBatchInternal::DeleteRange(rebuilding_trx_, column_family_id,
begin_key, end_key);
return Status::OK();
// else insert the values to the memtable right away
}
Status seek_status;
if (UNLIKELY(!SeekToColumnFamily(column_family_id, &seek_status))) {
bool batch_boundry = false;
if (rebuilding_trx_ != nullptr) {
assert(!write_after_commit_);
// The CF is probably flushed and hence no need for insert but we still
// need to keep track of the keys for upcoming rollback/commit.
WriteBatchInternal::DeleteRange(rebuilding_trx_, column_family_id,
begin_key, end_key);
// TODO(myabandeh): when transactional DeleteRange support is added,
// check if end_key must also be added.
batch_boundry = IsDuplicateKeySeq(column_family_id, begin_key);
}
MaybeAdvanceSeq(batch_boundry);
return seek_status;
}
if (db_ != nullptr) {
auto cf_handle = cf_mems_->GetColumnFamilyHandle();
if (cf_handle == nullptr) {
cf_handle = db_->DefaultColumnFamily();
}
auto* cfd = reinterpret_cast<ColumnFamilyHandleImpl*>(cf_handle)->cfd();
if (!cfd->is_delete_range_supported()) {
return Status::NotSupported(
std::string("DeleteRange not supported for table type ") +
cfd->ioptions()->table_factory->Name() + " in CF " +
cfd->GetName());
}
}
auto ret_status =
DeleteImpl(column_family_id, begin_key, end_key, kTypeRangeDeletion);
// optimize for non-recovery mode
if (UNLIKELY(!ret_status.IsTryAgain() && rebuilding_trx_ != nullptr)) {
assert(!write_after_commit_);
// If the ret_status is TryAgain then let the next try to add the ky to
// the rebuilding transaction object.
WriteBatchInternal::DeleteRange(rebuilding_trx_, column_family_id,
begin_key, end_key);
}
return ret_status;
}
Status MergeCF(uint32_t column_family_id, const Slice& key,
const Slice& value) override {
// optimize for non-recovery mode
if (UNLIKELY(write_after_commit_ && rebuilding_trx_ != nullptr)) {
WriteBatchInternal::Merge(rebuilding_trx_, column_family_id, key, value);
return Status::OK();
// else insert the values to the memtable right away
}
Status seek_status;
if (UNLIKELY(!SeekToColumnFamily(column_family_id, &seek_status))) {
bool batch_boundry = false;
if (rebuilding_trx_ != nullptr) {
assert(!write_after_commit_);
// The CF is probably flushed and hence no need for insert but we still
// need to keep track of the keys for upcoming rollback/commit.
WriteBatchInternal::Merge(rebuilding_trx_, column_family_id, key,
value);
batch_boundry = IsDuplicateKeySeq(column_family_id, key);
}
MaybeAdvanceSeq(batch_boundry);
return seek_status;
}
Status ret_status;
MemTable* mem = cf_mems_->GetMemTable();
auto* moptions = mem->GetImmutableMemTableOptions();
bool perform_merge = false;
assert(!concurrent_memtable_writes_ ||
moptions->max_successive_merges == 0);
// If we pass DB through and options.max_successive_merges is hit
// during recovery, Get() will be issued which will try to acquire
// DB mutex and cause deadlock, as DB mutex is already held.
// So we disable merge in recovery
if (moptions->max_successive_merges > 0 && db_ != nullptr &&
recovering_log_number_ == 0) {
assert(!concurrent_memtable_writes_);
LookupKey lkey(key, sequence_);
// Count the number of successive merges at the head
// of the key in the memtable
size_t num_merges = mem->CountSuccessiveMergeEntries(lkey);
if (num_merges >= moptions->max_successive_merges) {
perform_merge = true;
}
}
if (perform_merge) {
// 1) Get the existing value
std::string get_value;
// Pass in the sequence number so that we also include previous merge
// operations in the same batch.
SnapshotImpl read_from_snapshot;
read_from_snapshot.number_ = sequence_;
ReadOptions read_options;
read_options.snapshot = &read_from_snapshot;
auto cf_handle = cf_mems_->GetColumnFamilyHandle();
if (cf_handle == nullptr) {
cf_handle = db_->DefaultColumnFamily();
}
db_->Get(read_options, cf_handle, key, &get_value);
Slice get_value_slice = Slice(get_value);
// 2) Apply this merge
auto merge_operator = moptions->merge_operator;
assert(merge_operator);
std::string new_value;
Status merge_status = MergeHelper::TimedFullMerge(
merge_operator, key, &get_value_slice, {value}, &new_value,
moptions->info_log, moptions->statistics, Env::Default());
if (!merge_status.ok()) {
// Failed to merge!
// Store the delta in memtable
perform_merge = false;
} else {
// 3) Add value to memtable
assert(!concurrent_memtable_writes_);
bool mem_res = mem->Add(sequence_, kTypeValue, key, new_value);
if (UNLIKELY(!mem_res)) {
assert(seq_per_batch_);
ret_status = Status::TryAgain("key+seq exists");
const bool BATCH_BOUNDRY = true;
MaybeAdvanceSeq(BATCH_BOUNDRY);
}
}
}
if (!perform_merge) {
// Add merge operator to memtable
bool mem_res =
mem->Add(sequence_, kTypeMerge, key, value,
concurrent_memtable_writes_, get_post_process_info(mem));
if (UNLIKELY(!mem_res)) {
assert(seq_per_batch_);
ret_status = Status::TryAgain("key+seq exists");
const bool BATCH_BOUNDRY = true;
MaybeAdvanceSeq(BATCH_BOUNDRY);
}
}
// optimize for non-recovery mode
if (UNLIKELY(!ret_status.IsTryAgain() && rebuilding_trx_ != nullptr)) {
assert(!write_after_commit_);
// If the ret_status is TryAgain then let the next try to add the ky to
// the rebuilding transaction object.
WriteBatchInternal::Merge(rebuilding_trx_, column_family_id, key, value);
}
MaybeAdvanceSeq();
CheckMemtableFull();
return ret_status;
}
Status PutBlobIndexCF(uint32_t column_family_id, const Slice& key,
const Slice& value) override {
// Same as PutCF except for value type.
return PutCFImpl(column_family_id, key, value, kTypeBlobIndex);
}
void CheckMemtableFull() {
if (flush_scheduler_ != nullptr) {
auto* cfd = cf_mems_->current();
assert(cfd != nullptr);
if (cfd->mem()->ShouldScheduleFlush() &&
cfd->mem()->MarkFlushScheduled()) {
// MarkFlushScheduled only returns true if we are the one that
// should take action, so no need to dedup further
flush_scheduler_->ScheduleFlush(cfd);
}
}
}
// The write batch handler calls MarkBeginPrepare with unprepare set to true
// if it encounters the kTypeBeginUnprepareXID marker.
Status MarkBeginPrepare(bool unprepare) override {
assert(rebuilding_trx_ == nullptr);
assert(db_);
if (recovering_log_number_ != 0) {
// during recovery we rebuild a hollow transaction
// from all encountered prepare sections of the wal
if (db_->allow_2pc() == false) {
return Status::NotSupported(
"WAL contains prepared transactions. Open with "
"TransactionDB::Open().");
}
// we are now iterating through a prepared section
rebuilding_trx_ = new WriteBatch();
rebuilding_trx_seq_ = sequence_;
// We only call MarkBeginPrepare once per batch, and unprepared_batch_
// is initialized to false by default.
assert(!unprepared_batch_);
unprepared_batch_ = unprepare;
if (has_valid_writes_ != nullptr) {
*has_valid_writes_ = true;
}
}
return Status::OK();
}
Status MarkEndPrepare(const Slice& name) override {
assert(db_);
assert((rebuilding_trx_ != nullptr) == (recovering_log_number_ != 0));
if (recovering_log_number_ != 0) {
assert(db_->allow_2pc());
size_t batch_cnt =
write_after_commit_
? 0 // 0 will disable further checks
: static_cast<size_t>(sequence_ - rebuilding_trx_seq_ + 1);
db_->InsertRecoveredTransaction(recovering_log_number_, name.ToString(),
rebuilding_trx_, rebuilding_trx_seq_,
batch_cnt, unprepared_batch_);
rebuilding_trx_ = nullptr;
} else {
assert(rebuilding_trx_ == nullptr);
}
const bool batch_boundry = true;
MaybeAdvanceSeq(batch_boundry);
return Status::OK();
}
Status MarkNoop(bool empty_batch) override {
// A hack in pessimistic transaction could result into a noop at the start
// of the write batch, that should be ignored.
if (!empty_batch) {
// In the absence of Prepare markers, a kTypeNoop tag indicates the end of
// a batch. This happens when write batch commits skipping the prepare
// phase.
const bool batch_boundry = true;
MaybeAdvanceSeq(batch_boundry);
}
return Status::OK();
}
Status MarkCommit(const Slice& name) override {
assert(db_);
Status s;
if (recovering_log_number_ != 0) {
// in recovery when we encounter a commit marker
// we lookup this transaction in our set of rebuilt transactions
// and commit.
auto trx = db_->GetRecoveredTransaction(name.ToString());
// the log containing the prepared section may have
// been released in the last incarnation because the
// data was flushed to L0
if (trx != nullptr) {
// at this point individual CF lognumbers will prevent
// duplicate re-insertion of values.
assert(log_number_ref_ == 0);
if (write_after_commit_) {
// write_after_commit_ can only have one batch in trx.
assert(trx->batches_.size() == 1);
const auto& batch_info = trx->batches_.begin()->second;
// all inserts must reference this trx log number
log_number_ref_ = batch_info.log_number_;
s = batch_info.batch_->Iterate(this);
log_number_ref_ = 0;
}
// else the values are already inserted before the commit
if (s.ok()) {
db_->DeleteRecoveredTransaction(name.ToString());
}
if (has_valid_writes_ != nullptr) {
*has_valid_writes_ = true;
}
}
} else {
// When writes are not delayed until commit, there is no disconnect
// between a memtable write and the WAL that supports it. So the commit
// need not reference any log as the only log to which it depends.
assert(!write_after_commit_ || log_number_ref_ > 0);
}
const bool batch_boundry = true;
MaybeAdvanceSeq(batch_boundry);
return s;
}
Status MarkRollback(const Slice& name) override {
assert(db_);
if (recovering_log_number_ != 0) {
auto trx = db_->GetRecoveredTransaction(name.ToString());
// the log containing the transactions prep section
// may have been released in the previous incarnation
// because we knew it had been rolled back
if (trx != nullptr) {
db_->DeleteRecoveredTransaction(name.ToString());
}
} else {
// in non recovery we simply ignore this tag
}
const bool batch_boundry = true;
MaybeAdvanceSeq(batch_boundry);
return Status::OK();
}
private:
MemTablePostProcessInfo* get_post_process_info(MemTable* mem) {
if (!concurrent_memtable_writes_) {
// No need to batch counters locally if we don't use concurrent mode.
return nullptr;
}
return &GetPostMap()[mem];
}
};
// This function can only be called in these conditions:
// 1) During Recovery()
// 2) During Write(), in a single-threaded write thread
// 3) During Write(), in a concurrent context where memtables has been cloned
// The reason is that it calls memtables->Seek(), which has a stateful cache
Status WriteBatchInternal::InsertInto(
WriteThread::WriteGroup& write_group, SequenceNumber sequence,
ColumnFamilyMemTables* memtables, FlushScheduler* flush_scheduler,
bool ignore_missing_column_families, uint64_t recovery_log_number, DB* db,
bool concurrent_memtable_writes, bool seq_per_batch, bool batch_per_txn) {
MemTableInserter inserter(
sequence, memtables, flush_scheduler, ignore_missing_column_families,
recovery_log_number, db, concurrent_memtable_writes,
nullptr /*has_valid_writes*/, seq_per_batch, batch_per_txn);
for (auto w : write_group) {
if (w->CallbackFailed()) {
continue;
}
w->sequence = inserter.sequence();
if (!w->ShouldWriteToMemtable()) {
// In seq_per_batch_ mode this advances the seq by one.
inserter.MaybeAdvanceSeq(true);
continue;
}
SetSequence(w->batch, inserter.sequence());
inserter.set_log_number_ref(w->log_ref);
w->status = w->batch->Iterate(&inserter);
if (!w->status.ok()) {
return w->status;
}
assert(!seq_per_batch || w->batch_cnt != 0);
assert(!seq_per_batch || inserter.sequence() - w->sequence == w->batch_cnt);
}
return Status::OK();
}
Status WriteBatchInternal::InsertInto(
WriteThread::Writer* writer, SequenceNumber sequence,
ColumnFamilyMemTables* memtables, FlushScheduler* flush_scheduler,
bool ignore_missing_column_families, uint64_t log_number, DB* db,
bool concurrent_memtable_writes, bool seq_per_batch, size_t batch_cnt,
bool batch_per_txn) {
#ifdef NDEBUG
(void)batch_cnt;
#endif
assert(writer->ShouldWriteToMemtable());
MemTableInserter inserter(
sequence, memtables, flush_scheduler, ignore_missing_column_families,
log_number, db, concurrent_memtable_writes, nullptr /*has_valid_writes*/,
seq_per_batch, batch_per_txn);
SetSequence(writer->batch, sequence);
inserter.set_log_number_ref(writer->log_ref);
Status s = writer->batch->Iterate(&inserter);
assert(!seq_per_batch || batch_cnt != 0);
assert(!seq_per_batch || inserter.sequence() - sequence == batch_cnt);
if (concurrent_memtable_writes) {
inserter.PostProcess();
}
return s;
}
Status WriteBatchInternal::InsertInto(
const WriteBatch* batch, ColumnFamilyMemTables* memtables,
FlushScheduler* flush_scheduler, bool ignore_missing_column_families,
uint64_t log_number, DB* db, bool concurrent_memtable_writes,
SequenceNumber* next_seq, bool* has_valid_writes, bool seq_per_batch,
bool batch_per_txn) {
MemTableInserter inserter(Sequence(batch), memtables, flush_scheduler,
ignore_missing_column_families, log_number, db,
concurrent_memtable_writes, has_valid_writes,
seq_per_batch, batch_per_txn);
Status s = batch->Iterate(&inserter);
if (next_seq != nullptr) {
*next_seq = inserter.sequence();
}
if (concurrent_memtable_writes) {
inserter.PostProcess();
}
return s;
}
Status WriteBatchInternal::SetContents(WriteBatch* b, const Slice& contents) {
assert(contents.size() >= WriteBatchInternal::kHeader);
b->rep_.assign(contents.data(), contents.size());
b->content_flags_.store(ContentFlags::DEFERRED, std::memory_order_relaxed);
return Status::OK();
}
Status WriteBatchInternal::Append(WriteBatch* dst, const WriteBatch* src,
const bool wal_only) {
size_t src_len;
int src_count;
uint32_t src_flags;
const SavePoint& batch_end = src->GetWalTerminationPoint();
if (wal_only && !batch_end.is_cleared()) {
src_len = batch_end.size - WriteBatchInternal::kHeader;
src_count = batch_end.count;
src_flags = batch_end.content_flags;
} else {
src_len = src->rep_.size() - WriteBatchInternal::kHeader;
src_count = Count(src);
src_flags = src->content_flags_.load(std::memory_order_relaxed);
}
SetCount(dst, Count(dst) + src_count);
assert(src->rep_.size() >= WriteBatchInternal::kHeader);
dst->rep_.append(src->rep_.data() + WriteBatchInternal::kHeader, src_len);
dst->content_flags_.store(
dst->content_flags_.load(std::memory_order_relaxed) | src_flags,
std::memory_order_relaxed);
return Status::OK();
}
size_t WriteBatchInternal::AppendedByteSize(size_t leftByteSize,
size_t rightByteSize) {
if (leftByteSize == 0 || rightByteSize == 0) {
return leftByteSize + rightByteSize;
} else {
return leftByteSize + rightByteSize - WriteBatchInternal::kHeader;
}
}
} // namespace rocksdb