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rocksdb/utilities/blob_db/blob_db_impl.cc
Jay Zhuang 29102641dd Skip directory fsync for filesystem btrfs (#8903) 
Summary:
Directory fsync might be expensive on btrfs and it may not be needed.
Here are 4 directory fsync cases:
1. creating a new file: dir-fsync is not needed on btrfs, as long as the
   new file itself is synced.
2. renaming a file: dir-fsync is not needed if the renamed file is
   synced. So an API `FsyncAfterFileRename(filename, ...)` is provided
   to sync the file on btrfs. By default, it just calls dir-fsync.
3. deleting files: dir-fsync is forced by set
   `IOOptions.force_dir_fsync = true`
4. renaming multiple files (like backup and checkpoint): dir-fsync is
   forced, the same as above.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8903

Test Plan: run tests on btrfs and non btrfs

Reviewed By: ajkr

Differential Revision: D30885059

Pulled By: jay-zhuang

fbshipit-source-id: dd2730b31580b0bcaedffc318a762d7dbf25de4a
2021-11-03 12:21:27 -07:00

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// 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).
#ifndef ROCKSDB_LITE
#include "utilities/blob_db/blob_db_impl.h"
#include <algorithm>
#include <cinttypes>
#include <iomanip>
#include <memory>
#include <sstream>
#include "db/blob/blob_index.h"
#include "db/db_impl/db_impl.h"
#include "db/write_batch_internal.h"
#include "file/file_util.h"
#include "file/filename.h"
#include "file/random_access_file_reader.h"
#include "file/sst_file_manager_impl.h"
#include "file/writable_file_writer.h"
#include "logging/logging.h"
#include "monitoring/instrumented_mutex.h"
#include "monitoring/statistics.h"
#include "rocksdb/convenience.h"
#include "rocksdb/env.h"
#include "rocksdb/iterator.h"
#include "rocksdb/utilities/stackable_db.h"
#include "rocksdb/utilities/transaction.h"
#include "table/block_based/block.h"
#include "table/block_based/block_based_table_builder.h"
#include "table/block_based/block_builder.h"
#include "table/meta_blocks.h"
#include "test_util/sync_point.h"
#include "util/cast_util.h"
#include "util/crc32c.h"
#include "util/mutexlock.h"
#include "util/random.h"
#include "util/stop_watch.h"
#include "util/timer_queue.h"
#include "utilities/blob_db/blob_compaction_filter.h"
#include "utilities/blob_db/blob_db_iterator.h"
#include "utilities/blob_db/blob_db_listener.h"
namespace {
int kBlockBasedTableVersionFormat = 2;
} // end namespace
namespace ROCKSDB_NAMESPACE {
namespace blob_db {
bool BlobFileComparator::operator()(
const std::shared_ptr<BlobFile>& lhs,
const std::shared_ptr<BlobFile>& rhs) const {
return lhs->BlobFileNumber() > rhs->BlobFileNumber();
}
bool BlobFileComparatorTTL::operator()(
const std::shared_ptr<BlobFile>& lhs,
const std::shared_ptr<BlobFile>& rhs) const {
assert(lhs->HasTTL() && rhs->HasTTL());
if (lhs->expiration_range_.first < rhs->expiration_range_.first) {
return true;
}
if (lhs->expiration_range_.first > rhs->expiration_range_.first) {
return false;
}
return lhs->BlobFileNumber() < rhs->BlobFileNumber();
}
BlobDBImpl::BlobDBImpl(const std::string& dbname,
const BlobDBOptions& blob_db_options,
const DBOptions& db_options,
const ColumnFamilyOptions& cf_options)
: BlobDB(),
dbname_(dbname),
db_impl_(nullptr),
env_(db_options.env),
bdb_options_(blob_db_options),
db_options_(db_options),
cf_options_(cf_options),
file_options_(db_options),
statistics_(db_options_.statistics.get()),
next_file_number_(1),
flush_sequence_(0),
closed_(true),
open_file_count_(0),
total_blob_size_(0),
live_sst_size_(0),
fifo_eviction_seq_(0),
evict_expiration_up_to_(0),
debug_level_(0) {
clock_ = env_->GetSystemClock().get();
blob_dir_ = (bdb_options_.path_relative)
? dbname + "/" + bdb_options_.blob_dir
: bdb_options_.blob_dir;
file_options_.bytes_per_sync = blob_db_options.bytes_per_sync;
}
BlobDBImpl::~BlobDBImpl() {
tqueue_.shutdown();
// CancelAllBackgroundWork(db_, true);
Status s __attribute__((__unused__)) = Close();
assert(s.ok());
}
Status BlobDBImpl::Close() {
if (closed_) {
return Status::OK();
}
closed_ = true;
// Close base DB before BlobDBImpl destructs to stop event listener and
// compaction filter call.
Status s = db_->Close();
// delete db_ anyway even if close failed.
delete db_;
// Reset pointers to avoid StackableDB delete the pointer again.
db_ = nullptr;
db_impl_ = nullptr;
if (!s.ok()) {
return s;
}
s = SyncBlobFiles();
return s;
}
BlobDBOptions BlobDBImpl::GetBlobDBOptions() const { return bdb_options_; }
Status BlobDBImpl::Open(std::vector<ColumnFamilyHandle*>* handles) {
assert(handles != nullptr);
assert(db_ == nullptr);
if (blob_dir_.empty()) {
return Status::NotSupported("No blob directory in options");
}
if (bdb_options_.garbage_collection_cutoff < 0.0 ||
bdb_options_.garbage_collection_cutoff > 1.0) {
return Status::InvalidArgument(
"Garbage collection cutoff must be in the interval [0.0, 1.0]");
}
// Temporarily disable compactions in the base DB during open; save the user
// defined value beforehand so we can restore it once BlobDB is initialized.
// Note: this is only needed if garbage collection is enabled.
const bool disable_auto_compactions = cf_options_.disable_auto_compactions;
if (bdb_options_.enable_garbage_collection) {
cf_options_.disable_auto_compactions = true;
}
Status s;
// Create info log.
if (db_options_.info_log == nullptr) {
s = CreateLoggerFromOptions(dbname_, db_options_, &db_options_.info_log);
if (!s.ok()) {
return s;
}
}
ROCKS_LOG_INFO(db_options_.info_log, "Opening BlobDB...");
if ((cf_options_.compaction_filter != nullptr ||
cf_options_.compaction_filter_factory != nullptr)) {
ROCKS_LOG_INFO(db_options_.info_log,
"BlobDB only support compaction filter on non-TTL values.");
}
// Open blob directory.
s = env_->CreateDirIfMissing(blob_dir_);
if (!s.ok()) {
ROCKS_LOG_ERROR(db_options_.info_log,
"Failed to create blob_dir %s, status: %s",
blob_dir_.c_str(), s.ToString().c_str());
}
s = env_->GetFileSystem()->NewDirectory(blob_dir_, IOOptions(), &dir_ent_,
nullptr);
if (!s.ok()) {
ROCKS_LOG_ERROR(db_options_.info_log,
"Failed to open blob_dir %s, status: %s", blob_dir_.c_str(),
s.ToString().c_str());
return s;
}
// Open blob files.
s = OpenAllBlobFiles();
if (!s.ok()) {
return s;
}
// Update options
if (bdb_options_.enable_garbage_collection) {
db_options_.listeners.push_back(std::make_shared<BlobDBListenerGC>(this));
cf_options_.compaction_filter_factory =
std::make_shared<BlobIndexCompactionFilterFactoryGC>(
this, clock_, cf_options_, statistics_);
} else {
db_options_.listeners.push_back(std::make_shared<BlobDBListener>(this));
cf_options_.compaction_filter_factory =
std::make_shared<BlobIndexCompactionFilterFactory>(
this, clock_, cf_options_, statistics_);
}
// Reset user compaction filter after building into compaction factory.
cf_options_.compaction_filter = nullptr;
// Open base db.
ColumnFamilyDescriptor cf_descriptor(kDefaultColumnFamilyName, cf_options_);
s = DB::Open(db_options_, dbname_, {cf_descriptor}, handles, &db_);
if (!s.ok()) {
return s;
}
db_impl_ = static_cast_with_check<DBImpl>(db_->GetRootDB());
// Sanitize the blob_dir provided. Using a directory where the
// base DB stores its files for the default CF is not supported.
const ColumnFamilyData* const cfd =
static_cast<ColumnFamilyHandleImpl*>(DefaultColumnFamily())->cfd();
assert(cfd);
const ImmutableCFOptions* const ioptions = cfd->ioptions();
assert(ioptions);
assert(env_);
for (const auto& cf_path : ioptions->cf_paths) {
bool blob_dir_same_as_cf_dir = false;
s = env_->AreFilesSame(blob_dir_, cf_path.path, &blob_dir_same_as_cf_dir);
if (!s.ok()) {
ROCKS_LOG_ERROR(db_options_.info_log,
"Error while sanitizing blob_dir %s, status: %s",
blob_dir_.c_str(), s.ToString().c_str());
return s;
}
if (blob_dir_same_as_cf_dir) {
return Status::NotSupported(
"Using the base DB's storage directories for BlobDB files is not "
"supported.");
}
}
// Initialize SST file <-> oldest blob file mapping if garbage collection
// is enabled.
if (bdb_options_.enable_garbage_collection) {
std::vector<LiveFileMetaData> live_files;
db_->GetLiveFilesMetaData(&live_files);
InitializeBlobFileToSstMapping(live_files);
MarkUnreferencedBlobFilesObsoleteDuringOpen();
if (!disable_auto_compactions) {
s = db_->EnableAutoCompaction(*handles);
if (!s.ok()) {
ROCKS_LOG_ERROR(
db_options_.info_log,
"Failed to enable automatic compactions during open, status: %s",
s.ToString().c_str());
return s;
}
}
}
// Add trash files in blob dir to file delete scheduler.
SstFileManagerImpl* sfm = static_cast<SstFileManagerImpl*>(
db_impl_->immutable_db_options().sst_file_manager.get());
DeleteScheduler::CleanupDirectory(env_, sfm, blob_dir_);
UpdateLiveSSTSize();
// Start background jobs.
if (!bdb_options_.disable_background_tasks) {
StartBackgroundTasks();
}
ROCKS_LOG_INFO(db_options_.info_log, "BlobDB pointer %p", this);
bdb_options_.Dump(db_options_.info_log.get());
closed_ = false;
return s;
}
void BlobDBImpl::StartBackgroundTasks() {
// store a call to a member function and object
tqueue_.add(
kReclaimOpenFilesPeriodMillisecs,
std::bind(&BlobDBImpl::ReclaimOpenFiles, this, std::placeholders::_1));
tqueue_.add(
kDeleteObsoleteFilesPeriodMillisecs,
std::bind(&BlobDBImpl::DeleteObsoleteFiles, this, std::placeholders::_1));
tqueue_.add(kSanityCheckPeriodMillisecs,
std::bind(&BlobDBImpl::SanityCheck, this, std::placeholders::_1));
tqueue_.add(
kEvictExpiredFilesPeriodMillisecs,
std::bind(&BlobDBImpl::EvictExpiredFiles, this, std::placeholders::_1));
}
Status BlobDBImpl::GetAllBlobFiles(std::set<uint64_t>* file_numbers) {
assert(file_numbers != nullptr);
std::vector<std::string> all_files;
Status s = env_->GetChildren(blob_dir_, &all_files);
if (!s.ok()) {
ROCKS_LOG_ERROR(db_options_.info_log,
"Failed to get list of blob files, status: %s",
s.ToString().c_str());
return s;
}
for (const auto& file_name : all_files) {
uint64_t file_number;
FileType type;
bool success = ParseFileName(file_name, &file_number, &type);
if (success && type == kBlobFile) {
file_numbers->insert(file_number);
} else {
ROCKS_LOG_WARN(db_options_.info_log,
"Skipping file in blob directory: %s", file_name.c_str());
}
}
return s;
}
Status BlobDBImpl::OpenAllBlobFiles() {
std::set<uint64_t> file_numbers;
Status s = GetAllBlobFiles(&file_numbers);
if (!s.ok()) {
return s;
}
if (!file_numbers.empty()) {
next_file_number_.store(*file_numbers.rbegin() + 1);
}
std::ostringstream blob_file_oss;
std::ostringstream live_imm_oss;
std::ostringstream obsolete_file_oss;
for (auto& file_number : file_numbers) {
std::shared_ptr<BlobFile> blob_file = std::make_shared<BlobFile>(
this, blob_dir_, file_number, db_options_.info_log.get());
blob_file->MarkImmutable(/* sequence */ 0);
// Read file header and footer
Status read_metadata_status =
blob_file->ReadMetadata(env_->GetFileSystem(), file_options_);
if (read_metadata_status.IsCorruption()) {
// Remove incomplete file.
if (!obsolete_files_.empty()) {
obsolete_file_oss << ", ";
}
obsolete_file_oss << file_number;
ObsoleteBlobFile(blob_file, 0 /*obsolete_seq*/, false /*update_size*/);
continue;
} else if (!read_metadata_status.ok()) {
ROCKS_LOG_ERROR(db_options_.info_log,
"Unable to read metadata of blob file %" PRIu64
", status: '%s'",
file_number, read_metadata_status.ToString().c_str());
return read_metadata_status;
}
total_blob_size_ += blob_file->GetFileSize();
if (!blob_files_.empty()) {
blob_file_oss << ", ";
}
blob_file_oss << file_number;
blob_files_[file_number] = blob_file;
if (!blob_file->HasTTL()) {
if (!live_imm_non_ttl_blob_files_.empty()) {
live_imm_oss << ", ";
}
live_imm_oss << file_number;
live_imm_non_ttl_blob_files_[file_number] = blob_file;
}
}
ROCKS_LOG_INFO(db_options_.info_log,
"Found %" ROCKSDB_PRIszt " blob files: %s", blob_files_.size(),
blob_file_oss.str().c_str());
ROCKS_LOG_INFO(
db_options_.info_log, "Found %" ROCKSDB_PRIszt " non-TTL blob files: %s",
live_imm_non_ttl_blob_files_.size(), live_imm_oss.str().c_str());
ROCKS_LOG_INFO(db_options_.info_log,
"Found %" ROCKSDB_PRIszt
" incomplete or corrupted blob files: %s",
obsolete_files_.size(), obsolete_file_oss.str().c_str());
return s;
}
template <typename Linker>
void BlobDBImpl::LinkSstToBlobFileImpl(uint64_t sst_file_number,
uint64_t blob_file_number,
Linker linker) {
assert(bdb_options_.enable_garbage_collection);
assert(blob_file_number != kInvalidBlobFileNumber);
auto it = blob_files_.find(blob_file_number);
if (it == blob_files_.end()) {
ROCKS_LOG_WARN(db_options_.info_log,
"Blob file %" PRIu64
" not found while trying to link "
"SST file %" PRIu64,
blob_file_number, sst_file_number);
return;
}
BlobFile* const blob_file = it->second.get();
assert(blob_file);
linker(blob_file, sst_file_number);
ROCKS_LOG_INFO(db_options_.info_log,
"Blob file %" PRIu64 " linked to SST file %" PRIu64,
blob_file_number, sst_file_number);
}
void BlobDBImpl::LinkSstToBlobFile(uint64_t sst_file_number,
uint64_t blob_file_number) {
auto linker = [](BlobFile* blob_file, uint64_t sst_file) {
WriteLock file_lock(&blob_file->mutex_);
blob_file->LinkSstFile(sst_file);
};
LinkSstToBlobFileImpl(sst_file_number, blob_file_number, linker);
}
void BlobDBImpl::LinkSstToBlobFileNoLock(uint64_t sst_file_number,
uint64_t blob_file_number) {
auto linker = [](BlobFile* blob_file, uint64_t sst_file) {
blob_file->LinkSstFile(sst_file);
};
LinkSstToBlobFileImpl(sst_file_number, blob_file_number, linker);
}
void BlobDBImpl::UnlinkSstFromBlobFile(uint64_t sst_file_number,
uint64_t blob_file_number) {
assert(bdb_options_.enable_garbage_collection);
assert(blob_file_number != kInvalidBlobFileNumber);
auto it = blob_files_.find(blob_file_number);
if (it == blob_files_.end()) {
ROCKS_LOG_WARN(db_options_.info_log,
"Blob file %" PRIu64
" not found while trying to unlink "
"SST file %" PRIu64,
blob_file_number, sst_file_number);
return;
}
BlobFile* const blob_file = it->second.get();
assert(blob_file);
{
WriteLock file_lock(&blob_file->mutex_);
blob_file->UnlinkSstFile(sst_file_number);
}
ROCKS_LOG_INFO(db_options_.info_log,
"Blob file %" PRIu64 " unlinked from SST file %" PRIu64,
blob_file_number, sst_file_number);
}
void BlobDBImpl::InitializeBlobFileToSstMapping(
const std::vector<LiveFileMetaData>& live_files) {
assert(bdb_options_.enable_garbage_collection);
for (const auto& live_file : live_files) {
const uint64_t sst_file_number = live_file.file_number;
const uint64_t blob_file_number = live_file.oldest_blob_file_number;
if (blob_file_number == kInvalidBlobFileNumber) {
continue;
}
LinkSstToBlobFileNoLock(sst_file_number, blob_file_number);
}
}
void BlobDBImpl::ProcessFlushJobInfo(const FlushJobInfo& info) {
assert(bdb_options_.enable_garbage_collection);
WriteLock lock(&mutex_);
if (info.oldest_blob_file_number != kInvalidBlobFileNumber) {
LinkSstToBlobFile(info.file_number, info.oldest_blob_file_number);
}
assert(flush_sequence_ < info.largest_seqno);
flush_sequence_ = info.largest_seqno;
MarkUnreferencedBlobFilesObsolete();
}
void BlobDBImpl::ProcessCompactionJobInfo(const CompactionJobInfo& info) {
assert(bdb_options_.enable_garbage_collection);
if (!info.status.ok()) {
return;
}
// Note: the same SST file may appear in both the input and the output
// file list in case of a trivial move. We walk through the two lists
// below in a fashion that's similar to merge sort to detect this.
auto cmp = [](const CompactionFileInfo& lhs, const CompactionFileInfo& rhs) {
return lhs.file_number < rhs.file_number;
};
auto inputs = info.input_file_infos;
auto iit = inputs.begin();
const auto iit_end = inputs.end();
std::sort(iit, iit_end, cmp);
auto outputs = info.output_file_infos;
auto oit = outputs.begin();
const auto oit_end = outputs.end();
std::sort(oit, oit_end, cmp);
WriteLock lock(&mutex_);
while (iit != iit_end && oit != oit_end) {
const auto& input = *iit;
const auto& output = *oit;
if (input.file_number == output.file_number) {
++iit;
++oit;
} else if (input.file_number < output.file_number) {
if (input.oldest_blob_file_number != kInvalidBlobFileNumber) {
UnlinkSstFromBlobFile(input.file_number, input.oldest_blob_file_number);
}
++iit;
} else {
assert(output.file_number < input.file_number);
if (output.oldest_blob_file_number != kInvalidBlobFileNumber) {
LinkSstToBlobFile(output.file_number, output.oldest_blob_file_number);
}
++oit;
}
}
while (iit != iit_end) {
const auto& input = *iit;
if (input.oldest_blob_file_number != kInvalidBlobFileNumber) {
UnlinkSstFromBlobFile(input.file_number, input.oldest_blob_file_number);
}
++iit;
}
while (oit != oit_end) {
const auto& output = *oit;
if (output.oldest_blob_file_number != kInvalidBlobFileNumber) {
LinkSstToBlobFile(output.file_number, output.oldest_blob_file_number);
}
++oit;
}
MarkUnreferencedBlobFilesObsolete();
}
bool BlobDBImpl::MarkBlobFileObsoleteIfNeeded(
const std::shared_ptr<BlobFile>& blob_file, SequenceNumber obsolete_seq) {
assert(blob_file);
assert(!blob_file->HasTTL());
assert(blob_file->Immutable());
assert(bdb_options_.enable_garbage_collection);
// Note: FIFO eviction could have marked this file obsolete already.
if (blob_file->Obsolete()) {
return true;
}
// We cannot mark this file (or any higher-numbered files for that matter)
// obsolete if it is referenced by any memtables or SSTs. We keep track of
// the SSTs explicitly. To account for memtables, we keep track of the highest
// sequence number received in flush notifications, and we do not mark the
// blob file obsolete if there are still unflushed memtables from before
// the time the blob file was closed.
if (blob_file->GetImmutableSequence() > flush_sequence_ ||
!blob_file->GetLinkedSstFiles().empty()) {
return false;
}
ROCKS_LOG_INFO(db_options_.info_log,
"Blob file %" PRIu64 " is no longer needed, marking obsolete",
blob_file->BlobFileNumber());
ObsoleteBlobFile(blob_file, obsolete_seq, /* update_size */ true);
return true;
}
template <class Functor>
void BlobDBImpl::MarkUnreferencedBlobFilesObsoleteImpl(Functor mark_if_needed) {
assert(bdb_options_.enable_garbage_collection);
// Iterate through all live immutable non-TTL blob files, and mark them
// obsolete assuming no SST files or memtables rely on the blobs in them.
// Note: we need to stop as soon as we find a blob file that has any
// linked SSTs (or one potentially referenced by memtables).
uint64_t obsoleted_files = 0;
auto it = live_imm_non_ttl_blob_files_.begin();
while (it != live_imm_non_ttl_blob_files_.end()) {
const auto& blob_file = it->second;
assert(blob_file);
assert(blob_file->BlobFileNumber() == it->first);
assert(!blob_file->HasTTL());
assert(blob_file->Immutable());
// Small optimization: Obsolete() does an atomic read, so we can do
// this check without taking a lock on the blob file's mutex.
if (blob_file->Obsolete()) {
it = live_imm_non_ttl_blob_files_.erase(it);
continue;
}
if (!mark_if_needed(blob_file)) {
break;
}
it = live_imm_non_ttl_blob_files_.erase(it);
++obsoleted_files;
}
if (obsoleted_files > 0) {
ROCKS_LOG_INFO(db_options_.info_log,
"%" PRIu64 " blob file(s) marked obsolete by GC",
obsoleted_files);
RecordTick(statistics_, BLOB_DB_GC_NUM_FILES, obsoleted_files);
}
}
void BlobDBImpl::MarkUnreferencedBlobFilesObsolete() {
const SequenceNumber obsolete_seq = GetLatestSequenceNumber();
MarkUnreferencedBlobFilesObsoleteImpl(
[this, obsolete_seq](const std::shared_ptr<BlobFile>& blob_file) {
WriteLock file_lock(&blob_file->mutex_);
return MarkBlobFileObsoleteIfNeeded(blob_file, obsolete_seq);
});
}
void BlobDBImpl::MarkUnreferencedBlobFilesObsoleteDuringOpen() {
MarkUnreferencedBlobFilesObsoleteImpl(
[this](const std::shared_ptr<BlobFile>& blob_file) {
return MarkBlobFileObsoleteIfNeeded(blob_file, /* obsolete_seq */ 0);
});
}
void BlobDBImpl::CloseRandomAccessLocked(
const std::shared_ptr<BlobFile>& bfile) {
bfile->CloseRandomAccessLocked();
open_file_count_--;
}
Status BlobDBImpl::GetBlobFileReader(
const std::shared_ptr<BlobFile>& blob_file,
std::shared_ptr<RandomAccessFileReader>* reader) {
assert(reader != nullptr);
bool fresh_open = false;
Status s = blob_file->GetReader(env_, file_options_, reader, &fresh_open);
if (s.ok() && fresh_open) {
assert(*reader != nullptr);
open_file_count_++;
}
return s;
}
std::shared_ptr<BlobFile> BlobDBImpl::NewBlobFile(
bool has_ttl, const ExpirationRange& expiration_range,
const std::string& reason) {
assert(has_ttl == (expiration_range.first || expiration_range.second));
uint64_t file_num = next_file_number_++;
const uint32_t column_family_id =
static_cast<ColumnFamilyHandleImpl*>(DefaultColumnFamily())->GetID();
auto blob_file = std::make_shared<BlobFile>(
this, blob_dir_, file_num, db_options_.info_log.get(), column_family_id,
bdb_options_.compression, has_ttl, expiration_range);
ROCKS_LOG_DEBUG(db_options_.info_log, "New blob file created: %s reason='%s'",
blob_file->PathName().c_str(), reason.c_str());
LogFlush(db_options_.info_log);
return blob_file;
}
void BlobDBImpl::RegisterBlobFile(std::shared_ptr<BlobFile> blob_file) {
const uint64_t blob_file_number = blob_file->BlobFileNumber();
auto it = blob_files_.lower_bound(blob_file_number);
assert(it == blob_files_.end() || it->first != blob_file_number);
blob_files_.insert(it,
std::map<uint64_t, std::shared_ptr<BlobFile>>::value_type(
blob_file_number, std::move(blob_file)));
}
Status BlobDBImpl::CreateWriterLocked(const std::shared_ptr<BlobFile>& bfile) {
std::string fpath(bfile->PathName());
std::unique_ptr<FSWritableFile> wfile;
const auto& fs = env_->GetFileSystem();
Status s = fs->ReopenWritableFile(fpath, file_options_, &wfile, nullptr);
if (!s.ok()) {
ROCKS_LOG_ERROR(db_options_.info_log,
"Failed to open blob file for write: %s status: '%s'"
" exists: '%s'",
fpath.c_str(), s.ToString().c_str(),
fs->FileExists(fpath, file_options_.io_options, nullptr)
.ToString()
.c_str());
return s;
}
std::unique_ptr<WritableFileWriter> fwriter;
fwriter.reset(new WritableFileWriter(std::move(wfile), fpath, file_options_));
uint64_t boffset = bfile->GetFileSize();
if (debug_level_ >= 2 && boffset) {
ROCKS_LOG_DEBUG(db_options_.info_log,
"Open blob file: %s with offset: %" PRIu64, fpath.c_str(),
boffset);
}
BlobLogWriter::ElemType et = BlobLogWriter::kEtNone;
if (bfile->file_size_ == BlobLogHeader::kSize) {
et = BlobLogWriter::kEtFileHdr;
} else if (bfile->file_size_ > BlobLogHeader::kSize) {
et = BlobLogWriter::kEtRecord;
} else if (bfile->file_size_) {
ROCKS_LOG_WARN(db_options_.info_log,
"Open blob file: %s with wrong size: %" PRIu64,
fpath.c_str(), boffset);
return Status::Corruption("Invalid blob file size");
}
constexpr bool do_flush = true;
bfile->log_writer_ = std::make_shared<BlobLogWriter>(
std::move(fwriter), clock_, statistics_, bfile->file_number_,
db_options_.use_fsync, do_flush, boffset);
bfile->log_writer_->last_elem_type_ = et;
return s;
}
std::shared_ptr<BlobFile> BlobDBImpl::FindBlobFileLocked(
uint64_t expiration) const {
if (open_ttl_files_.empty()) {
return nullptr;
}
std::shared_ptr<BlobFile> tmp = std::make_shared<BlobFile>();
tmp->SetHasTTL(true);
tmp->expiration_range_ = std::make_pair(expiration, 0);
tmp->file_number_ = std::numeric_limits<uint64_t>::max();
auto citr = open_ttl_files_.equal_range(tmp);
if (citr.first == open_ttl_files_.end()) {
assert(citr.second == open_ttl_files_.end());
std::shared_ptr<BlobFile> check = *(open_ttl_files_.rbegin());
return (check->expiration_range_.second <= expiration) ? nullptr : check;
}
if (citr.first != citr.second) {
return *(citr.first);
}
auto finditr = citr.second;
if (finditr != open_ttl_files_.begin()) {
--finditr;
}
bool b2 = (*finditr)->expiration_range_.second <= expiration;
bool b1 = (*finditr)->expiration_range_.first > expiration;
return (b1 || b2) ? nullptr : (*finditr);
}
Status BlobDBImpl::CheckOrCreateWriterLocked(
const std::shared_ptr<BlobFile>& blob_file,
std::shared_ptr<BlobLogWriter>* writer) {
assert(writer != nullptr);
*writer = blob_file->GetWriter();
if (*writer != nullptr) {
return Status::OK();
}
Status s = CreateWriterLocked(blob_file);
if (s.ok()) {
*writer = blob_file->GetWriter();
}
return s;
}
Status BlobDBImpl::CreateBlobFileAndWriter(
bool has_ttl, const ExpirationRange& expiration_range,
const std::string& reason, std::shared_ptr<BlobFile>* blob_file,
std::shared_ptr<BlobLogWriter>* writer) {
TEST_SYNC_POINT("BlobDBImpl::CreateBlobFileAndWriter");
assert(has_ttl == (expiration_range.first || expiration_range.second));
assert(blob_file);
assert(writer);
*blob_file = NewBlobFile(has_ttl, expiration_range, reason);
assert(*blob_file);
// file not visible, hence no lock
Status s = CheckOrCreateWriterLocked(*blob_file, writer);
if (!s.ok()) {
ROCKS_LOG_ERROR(db_options_.info_log,
"Failed to get writer for blob file: %s, error: %s",
(*blob_file)->PathName().c_str(), s.ToString().c_str());
return s;
}
assert(*writer);
s = (*writer)->WriteHeader((*blob_file)->header_);
if (!s.ok()) {
ROCKS_LOG_ERROR(db_options_.info_log,
"Failed to write header to new blob file: %s"
" status: '%s'",
(*blob_file)->PathName().c_str(), s.ToString().c_str());
return s;
}
(*blob_file)->SetFileSize(BlobLogHeader::kSize);
total_blob_size_ += BlobLogHeader::kSize;
return s;
}
Status BlobDBImpl::SelectBlobFile(std::shared_ptr<BlobFile>* blob_file) {
assert(blob_file);
{
ReadLock rl(&mutex_);
if (open_non_ttl_file_) {
assert(!open_non_ttl_file_->Immutable());
*blob_file = open_non_ttl_file_;
return Status::OK();
}
}
// Check again
WriteLock wl(&mutex_);
if (open_non_ttl_file_) {
assert(!open_non_ttl_file_->Immutable());
*blob_file = open_non_ttl_file_;
return Status::OK();
}
std::shared_ptr<BlobLogWriter> writer;
const Status s = CreateBlobFileAndWriter(
/* has_ttl */ false, ExpirationRange(),
/* reason */ "SelectBlobFile", blob_file, &writer);
if (!s.ok()) {
return s;
}
RegisterBlobFile(*blob_file);
open_non_ttl_file_ = *blob_file;
return s;
}
Status BlobDBImpl::SelectBlobFileTTL(uint64_t expiration,
std::shared_ptr<BlobFile>* blob_file) {
assert(blob_file);
assert(expiration != kNoExpiration);
{
ReadLock rl(&mutex_);
*blob_file = FindBlobFileLocked(expiration);
if (*blob_file != nullptr) {
assert(!(*blob_file)->Immutable());
return Status::OK();
}
}
// Check again
WriteLock wl(&mutex_);
*blob_file = FindBlobFileLocked(expiration);
if (*blob_file != nullptr) {
assert(!(*blob_file)->Immutable());
return Status::OK();
}
const uint64_t exp_low =
(expiration / bdb_options_.ttl_range_secs) * bdb_options_.ttl_range_secs;
const uint64_t exp_high = exp_low + bdb_options_.ttl_range_secs;
const ExpirationRange expiration_range(exp_low, exp_high);
std::ostringstream oss;
oss << "SelectBlobFileTTL range: [" << exp_low << ',' << exp_high << ')';
std::shared_ptr<BlobLogWriter> writer;
const Status s =
CreateBlobFileAndWriter(/* has_ttl */ true, expiration_range,
/* reason */ oss.str(), blob_file, &writer);
if (!s.ok()) {
return s;
}
RegisterBlobFile(*blob_file);
open_ttl_files_.insert(*blob_file);
return s;
}
class BlobDBImpl::BlobInserter : public WriteBatch::Handler {
private:
const WriteOptions& options_;
BlobDBImpl* blob_db_impl_;
uint32_t default_cf_id_;
WriteBatch batch_;
public:
BlobInserter(const WriteOptions& options, BlobDBImpl* blob_db_impl,
uint32_t default_cf_id)
: options_(options),
blob_db_impl_(blob_db_impl),
default_cf_id_(default_cf_id) {}
WriteBatch* batch() { return &batch_; }
Status PutCF(uint32_t column_family_id, const Slice& key,
const Slice& value) override {
if (column_family_id != default_cf_id_) {
return Status::NotSupported(
"Blob DB doesn't support non-default column family.");
}
Status s = blob_db_impl_->PutBlobValue(options_, key, value, kNoExpiration,
&batch_);
return s;
}
Status DeleteCF(uint32_t column_family_id, const Slice& key) override {
if (column_family_id != default_cf_id_) {
return Status::NotSupported(
"Blob DB doesn't support non-default column family.");
}
Status s = WriteBatchInternal::Delete(&batch_, column_family_id, key);
return s;
}
virtual Status DeleteRange(uint32_t column_family_id, const Slice& begin_key,
const Slice& end_key) {
if (column_family_id != default_cf_id_) {
return Status::NotSupported(
"Blob DB doesn't support non-default column family.");
}
Status s = WriteBatchInternal::DeleteRange(&batch_, column_family_id,
begin_key, end_key);
return s;
}
Status SingleDeleteCF(uint32_t /*column_family_id*/,
const Slice& /*key*/) override {
return Status::NotSupported("Not supported operation in blob db.");
}
Status MergeCF(uint32_t /*column_family_id*/, const Slice& /*key*/,
const Slice& /*value*/) override {
return Status::NotSupported("Not supported operation in blob db.");
}
void LogData(const Slice& blob) override { batch_.PutLogData(blob); }
};
Status BlobDBImpl::Write(const WriteOptions& options, WriteBatch* updates) {
StopWatch write_sw(clock_, statistics_, BLOB_DB_WRITE_MICROS);
RecordTick(statistics_, BLOB_DB_NUM_WRITE);
uint32_t default_cf_id =
static_cast_with_check<ColumnFamilyHandleImpl>(DefaultColumnFamily())
->GetID();
Status s;
BlobInserter blob_inserter(options, this, default_cf_id);
{
// Release write_mutex_ before DB write to avoid race condition with
// flush begin listener, which also require write_mutex_ to sync
// blob files.
MutexLock l(&write_mutex_);
s = updates->Iterate(&blob_inserter);
}
if (!s.ok()) {
return s;
}
return db_->Write(options, blob_inserter.batch());
}
Status BlobDBImpl::Put(const WriteOptions& options, const Slice& key,
const Slice& value) {
return PutUntil(options, key, value, kNoExpiration);
}
Status BlobDBImpl::PutWithTTL(const WriteOptions& options,
const Slice& key, const Slice& value,
uint64_t ttl) {
uint64_t now = EpochNow();
uint64_t expiration = kNoExpiration - now > ttl ? now + ttl : kNoExpiration;
return PutUntil(options, key, value, expiration);
}
Status BlobDBImpl::PutUntil(const WriteOptions& options, const Slice& key,
const Slice& value, uint64_t expiration) {
StopWatch write_sw(clock_, statistics_, BLOB_DB_WRITE_MICROS);
RecordTick(statistics_, BLOB_DB_NUM_PUT);
Status s;
WriteBatch batch;
{
// Release write_mutex_ before DB write to avoid race condition with
// flush begin listener, which also require write_mutex_ to sync
// blob files.
MutexLock l(&write_mutex_);
s = PutBlobValue(options, key, value, expiration, &batch);
}
if (s.ok()) {
s = db_->Write(options, &batch);
}
return s;
}
Status BlobDBImpl::PutBlobValue(const WriteOptions& /*options*/,
const Slice& key, const Slice& value,
uint64_t expiration, WriteBatch* batch) {
write_mutex_.AssertHeld();
Status s;
std::string index_entry;
uint32_t column_family_id =
static_cast_with_check<ColumnFamilyHandleImpl>(DefaultColumnFamily())
->GetID();
if (value.size() < bdb_options_.min_blob_size) {
if (expiration == kNoExpiration) {
// Put as normal value
s = batch->Put(key, value);
RecordTick(statistics_, BLOB_DB_WRITE_INLINED);
} else {
// Inlined with TTL
BlobIndex::EncodeInlinedTTL(&index_entry, expiration, value);
s = WriteBatchInternal::PutBlobIndex(batch, column_family_id, key,
index_entry);
RecordTick(statistics_, BLOB_DB_WRITE_INLINED_TTL);
}
} else {
std::string compression_output;
Slice value_compressed = GetCompressedSlice(value, &compression_output);
std::string headerbuf;
BlobLogWriter::ConstructBlobHeader(&headerbuf, key, value_compressed,
expiration);
// Check DB size limit before selecting blob file to
// Since CheckSizeAndEvictBlobFiles() can close blob files, it needs to be
// done before calling SelectBlobFile().
s = CheckSizeAndEvictBlobFiles(headerbuf.size() + key.size() +
value_compressed.size());
if (!s.ok()) {
return s;
}
std::shared_ptr<BlobFile> blob_file;
if (expiration != kNoExpiration) {
s = SelectBlobFileTTL(expiration, &blob_file);
} else {
s = SelectBlobFile(&blob_file);
}
if (s.ok()) {
assert(blob_file != nullptr);
assert(blob_file->GetCompressionType() == bdb_options_.compression);
s = AppendBlob(blob_file, headerbuf, key, value_compressed, expiration,
&index_entry);
}
if (s.ok()) {
if (expiration != kNoExpiration) {
WriteLock file_lock(&blob_file->mutex_);
blob_file->ExtendExpirationRange(expiration);
}
s = CloseBlobFileIfNeeded(blob_file);
}
if (s.ok()) {
s = WriteBatchInternal::PutBlobIndex(batch, column_family_id, key,
index_entry);
}
if (s.ok()) {
if (expiration == kNoExpiration) {
RecordTick(statistics_, BLOB_DB_WRITE_BLOB);
} else {
RecordTick(statistics_, BLOB_DB_WRITE_BLOB_TTL);
}
} else {
ROCKS_LOG_ERROR(
db_options_.info_log,
"Failed to append blob to FILE: %s: KEY: %s VALSZ: %" ROCKSDB_PRIszt
" status: '%s' blob_file: '%s'",
blob_file->PathName().c_str(), key.ToString().c_str(), value.size(),
s.ToString().c_str(), blob_file->DumpState().c_str());
}
}
RecordTick(statistics_, BLOB_DB_NUM_KEYS_WRITTEN);
RecordTick(statistics_, BLOB_DB_BYTES_WRITTEN, key.size() + value.size());
RecordInHistogram(statistics_, BLOB_DB_KEY_SIZE, key.size());
RecordInHistogram(statistics_, BLOB_DB_VALUE_SIZE, value.size());
return s;
}
Slice BlobDBImpl::GetCompressedSlice(const Slice& raw,
std::string* compression_output) const {
if (bdb_options_.compression == kNoCompression) {
return raw;
}
StopWatch compression_sw(clock_, statistics_, BLOB_DB_COMPRESSION_MICROS);
CompressionType type = bdb_options_.compression;
CompressionOptions opts;
CompressionContext context(type);
CompressionInfo info(opts, context, CompressionDict::GetEmptyDict(), type,
0 /* sample_for_compression */);
CompressBlock(raw, info, &type, kBlockBasedTableVersionFormat, false,
compression_output, nullptr, nullptr);
return *compression_output;
}
Status BlobDBImpl::DecompressSlice(const Slice& compressed_value,
CompressionType compression_type,
PinnableSlice* value_output) const {
assert(compression_type != kNoCompression);
BlockContents contents;
auto cfh = static_cast<ColumnFamilyHandleImpl*>(DefaultColumnFamily());
{
StopWatch decompression_sw(clock_, statistics_,
BLOB_DB_DECOMPRESSION_MICROS);
UncompressionContext context(compression_type);
UncompressionInfo info(context, UncompressionDict::GetEmptyDict(),
compression_type);
Status s = UncompressBlockContentsForCompressionType(
info, compressed_value.data(), compressed_value.size(), &contents,
kBlockBasedTableVersionFormat, *(cfh->cfd()->ioptions()));
if (!s.ok()) {
return Status::Corruption("Unable to decompress blob.");
}
}
value_output->PinSelf(contents.data);
return Status::OK();
}
Status BlobDBImpl::CompactFiles(
const CompactionOptions& compact_options,
const std::vector<std::string>& input_file_names, const int output_level,
const int output_path_id, std::vector<std::string>* const output_file_names,
CompactionJobInfo* compaction_job_info) {
// Note: we need CompactionJobInfo to be able to track updates to the
// blob file <-> SST mappings, so we provide one if the user hasn't,
// assuming that GC is enabled.
CompactionJobInfo info{};
if (bdb_options_.enable_garbage_collection && !compaction_job_info) {
compaction_job_info = &info;
}
const Status s =
db_->CompactFiles(compact_options, input_file_names, output_level,
output_path_id, output_file_names, compaction_job_info);
if (!s.ok()) {
return s;
}
if (bdb_options_.enable_garbage_collection) {
assert(compaction_job_info);
ProcessCompactionJobInfo(*compaction_job_info);
}
return s;
}
void BlobDBImpl::GetCompactionContextCommon(BlobCompactionContext* context) {
assert(context);
context->blob_db_impl = this;
context->next_file_number = next_file_number_.load();
context->current_blob_files.clear();
for (auto& p : blob_files_) {
context->current_blob_files.insert(p.first);
}
context->fifo_eviction_seq = fifo_eviction_seq_;
context->evict_expiration_up_to = evict_expiration_up_to_;
}
void BlobDBImpl::GetCompactionContext(BlobCompactionContext* context) {
assert(context);
ReadLock l(&mutex_);
GetCompactionContextCommon(context);
}
void BlobDBImpl::GetCompactionContext(BlobCompactionContext* context,
BlobCompactionContextGC* context_gc) {
assert(context);
assert(context_gc);
ReadLock l(&mutex_);
GetCompactionContextCommon(context);
if (!live_imm_non_ttl_blob_files_.empty()) {
auto it = live_imm_non_ttl_blob_files_.begin();
std::advance(it, bdb_options_.garbage_collection_cutoff *
live_imm_non_ttl_blob_files_.size());
context_gc->cutoff_file_number = it != live_imm_non_ttl_blob_files_.end()
? it->first
: std::numeric_limits<uint64_t>::max();
}
}
void BlobDBImpl::UpdateLiveSSTSize() {
uint64_t live_sst_size = 0;
bool ok = GetIntProperty(DB::Properties::kLiveSstFilesSize, &live_sst_size);
if (ok) {
live_sst_size_.store(live_sst_size);
ROCKS_LOG_INFO(db_options_.info_log,
"Updated total SST file size: %" PRIu64 " bytes.",
live_sst_size);
} else {
ROCKS_LOG_ERROR(
db_options_.info_log,
"Failed to update total SST file size after flush or compaction.");
}
{
// Trigger FIFO eviction if needed.
MutexLock l(&write_mutex_);
Status s = CheckSizeAndEvictBlobFiles(0, true /*force*/);
if (s.IsNoSpace()) {
ROCKS_LOG_WARN(db_options_.info_log,
"DB grow out-of-space after SST size updated. Current live"
" SST size: %" PRIu64
" , current blob files size: %" PRIu64 ".",
live_sst_size_.load(), total_blob_size_.load());
}
}
}
Status BlobDBImpl::CheckSizeAndEvictBlobFiles(uint64_t blob_size,
bool force_evict) {
write_mutex_.AssertHeld();
uint64_t live_sst_size = live_sst_size_.load();
if (bdb_options_.max_db_size == 0 ||
live_sst_size + total_blob_size_.load() + blob_size <=
bdb_options_.max_db_size) {
return Status::OK();
}
if (bdb_options_.is_fifo == false ||
(!force_evict && live_sst_size + blob_size > bdb_options_.max_db_size)) {
// FIFO eviction is disabled, or no space to insert new blob even we evict
// all blob files.
return Status::NoSpace(
"Write failed, as writing it would exceed max_db_size limit.");
}
std::vector<std::shared_ptr<BlobFile>> candidate_files;
CopyBlobFiles(&candidate_files);
std::sort(candidate_files.begin(), candidate_files.end(),
BlobFileComparator());
fifo_eviction_seq_ = GetLatestSequenceNumber();
WriteLock l(&mutex_);
while (!candidate_files.empty() &&
live_sst_size + total_blob_size_.load() + blob_size >
bdb_options_.max_db_size) {
std::shared_ptr<BlobFile> blob_file = candidate_files.back();
candidate_files.pop_back();
WriteLock file_lock(&blob_file->mutex_);
if (blob_file->Obsolete()) {
// File already obsoleted by someone else.
assert(blob_file->Immutable());
continue;
}
// FIFO eviction can evict open blob files.
if (!blob_file->Immutable()) {
Status s = CloseBlobFile(blob_file);
if (!s.ok()) {
return s;
}
}
assert(blob_file->Immutable());
auto expiration_range = blob_file->GetExpirationRange();
ROCKS_LOG_INFO(db_options_.info_log,
"Evict oldest blob file since DB out of space. Current "
"live SST file size: %" PRIu64 ", total blob size: %" PRIu64
", max db size: %" PRIu64 ", evicted blob file #%" PRIu64
".",
live_sst_size, total_blob_size_.load(),
bdb_options_.max_db_size, blob_file->BlobFileNumber());
ObsoleteBlobFile(blob_file, fifo_eviction_seq_, true /*update_size*/);
evict_expiration_up_to_ = expiration_range.first;
RecordTick(statistics_, BLOB_DB_FIFO_NUM_FILES_EVICTED);
RecordTick(statistics_, BLOB_DB_FIFO_NUM_KEYS_EVICTED,
blob_file->BlobCount());
RecordTick(statistics_, BLOB_DB_FIFO_BYTES_EVICTED,
blob_file->GetFileSize());
TEST_SYNC_POINT("BlobDBImpl::EvictOldestBlobFile:Evicted");
}
if (live_sst_size + total_blob_size_.load() + blob_size >
bdb_options_.max_db_size) {
return Status::NoSpace(
"Write failed, as writing it would exceed max_db_size limit.");
}
return Status::OK();
}
Status BlobDBImpl::AppendBlob(const std::shared_ptr<BlobFile>& bfile,
const std::string& headerbuf, const Slice& key,
const Slice& value, uint64_t expiration,
std::string* index_entry) {
Status s;
uint64_t blob_offset = 0;
uint64_t key_offset = 0;
{
WriteLock lockbfile_w(&bfile->mutex_);
std::shared_ptr<BlobLogWriter> writer;
s = CheckOrCreateWriterLocked(bfile, &writer);
if (!s.ok()) {
return s;
}
// write the blob to the blob log.
s = writer->EmitPhysicalRecord(headerbuf, key, value, &key_offset,
&blob_offset);
}
if (!s.ok()) {
ROCKS_LOG_ERROR(db_options_.info_log,
"Invalid status in AppendBlob: %s status: '%s'",
bfile->PathName().c_str(), s.ToString().c_str());
return s;
}
uint64_t size_put = headerbuf.size() + key.size() + value.size();
bfile->BlobRecordAdded(size_put);
total_blob_size_ += size_put;
if (expiration == kNoExpiration) {
BlobIndex::EncodeBlob(index_entry, bfile->BlobFileNumber(), blob_offset,
value.size(), bdb_options_.compression);
} else {
BlobIndex::EncodeBlobTTL(index_entry, expiration, bfile->BlobFileNumber(),
blob_offset, value.size(),
bdb_options_.compression);
}
return s;
}
std::vector<Status> BlobDBImpl::MultiGet(
const ReadOptions& read_options,
const std::vector<Slice>& keys, std::vector<std::string>* values) {
StopWatch multiget_sw(clock_, statistics_, BLOB_DB_MULTIGET_MICROS);
RecordTick(statistics_, BLOB_DB_NUM_MULTIGET);
// Get a snapshot to avoid blob file get deleted between we
// fetch and index entry and reading from the file.
ReadOptions ro(read_options);
bool snapshot_created = SetSnapshotIfNeeded(&ro);
std::vector<Status> statuses;
statuses.reserve(keys.size());
values->clear();
values->reserve(keys.size());
PinnableSlice value;
for (size_t i = 0; i < keys.size(); i++) {
statuses.push_back(Get(ro, DefaultColumnFamily(), keys[i], &value));
values->push_back(value.ToString());
value.Reset();
}
if (snapshot_created) {
db_->ReleaseSnapshot(ro.snapshot);
}
return statuses;
}
bool BlobDBImpl::SetSnapshotIfNeeded(ReadOptions* read_options) {
assert(read_options != nullptr);
if (read_options->snapshot != nullptr) {
return false;
}
read_options->snapshot = db_->GetSnapshot();
return true;
}
Status BlobDBImpl::GetBlobValue(const Slice& key, const Slice& index_entry,
PinnableSlice* value, uint64_t* expiration) {
assert(value);
BlobIndex blob_index;
Status s = blob_index.DecodeFrom(index_entry);
if (!s.ok()) {
return s;
}
if (blob_index.HasTTL() && blob_index.expiration() <= EpochNow()) {
return Status::NotFound("Key expired");
}
if (expiration != nullptr) {
if (blob_index.HasTTL()) {
*expiration = blob_index.expiration();
} else {
*expiration = kNoExpiration;
}
}
if (blob_index.IsInlined()) {
// TODO(yiwu): If index_entry is a PinnableSlice, we can also pin the same
// memory buffer to avoid extra copy.
value->PinSelf(blob_index.value());
return Status::OK();
}
CompressionType compression_type = kNoCompression;
s = GetRawBlobFromFile(key, blob_index.file_number(), blob_index.offset(),
blob_index.size(), value, &compression_type);
if (!s.ok()) {
return s;
}
if (compression_type != kNoCompression) {
s = DecompressSlice(*value, compression_type, value);
if (!s.ok()) {
if (debug_level_ >= 2) {
ROCKS_LOG_ERROR(
db_options_.info_log,
"Uncompression error during blob read from file: %" PRIu64
" blob_offset: %" PRIu64 " blob_size: %" PRIu64
" key: %s status: '%s'",
blob_index.file_number(), blob_index.offset(), blob_index.size(),
key.ToString(/* output_hex */ true).c_str(), s.ToString().c_str());
}
return s;
}
}
return Status::OK();
}
Status BlobDBImpl::GetRawBlobFromFile(const Slice& key, uint64_t file_number,
uint64_t offset, uint64_t size,
PinnableSlice* value,
CompressionType* compression_type) {
assert(value);
assert(compression_type);
assert(*compression_type == kNoCompression);
if (!size) {
value->PinSelf("");
return Status::OK();
}
// offset has to have certain min, as we will read CRC
// later from the Blob Header, which needs to be also a
// valid offset.
if (offset <
(BlobLogHeader::kSize + BlobLogRecord::kHeaderSize + key.size())) {
if (debug_level_ >= 2) {
ROCKS_LOG_ERROR(db_options_.info_log,
"Invalid blob index file_number: %" PRIu64
" blob_offset: %" PRIu64 " blob_size: %" PRIu64
" key: %s",
file_number, offset, size,
key.ToString(/* output_hex */ true).c_str());
}
return Status::NotFound("Invalid blob offset");
}
std::shared_ptr<BlobFile> blob_file;
{
ReadLock rl(&mutex_);
auto it = blob_files_.find(file_number);
// file was deleted
if (it == blob_files_.end()) {
return Status::NotFound("Blob Not Found as blob file missing");
}
blob_file = it->second;
}
*compression_type = blob_file->GetCompressionType();
// takes locks when called
std::shared_ptr<RandomAccessFileReader> reader;
Status s = GetBlobFileReader(blob_file, &reader);
if (!s.ok()) {
return s;
}
assert(offset >= key.size() + sizeof(uint32_t));
const uint64_t record_offset = offset - key.size() - sizeof(uint32_t);
const uint64_t record_size = sizeof(uint32_t) + key.size() + size;
// Allocate the buffer. This is safe in C++11
std::string buf;
AlignedBuf aligned_buf;
// A partial blob record contain checksum, key and value.
Slice blob_record;
{
StopWatch read_sw(clock_, statistics_, BLOB_DB_BLOB_FILE_READ_MICROS);
if (reader->use_direct_io()) {
s = reader->Read(IOOptions(), record_offset,
static_cast<size_t>(record_size), &blob_record, nullptr,
&aligned_buf);
} else {
buf.reserve(static_cast<size_t>(record_size));
s = reader->Read(IOOptions(), record_offset,
static_cast<size_t>(record_size), &blob_record, &buf[0],
nullptr);
}
RecordTick(statistics_, BLOB_DB_BLOB_FILE_BYTES_READ, blob_record.size());
}
if (!s.ok()) {
ROCKS_LOG_DEBUG(
db_options_.info_log,
"Failed to read blob from blob file %" PRIu64 ", blob_offset: %" PRIu64
", blob_size: %" PRIu64 ", key_size: %" ROCKSDB_PRIszt ", status: '%s'",
file_number, offset, size, key.size(), s.ToString().c_str());
return s;
}
if (blob_record.size() != record_size) {
ROCKS_LOG_DEBUG(
db_options_.info_log,
"Failed to read blob from blob file %" PRIu64 ", blob_offset: %" PRIu64
", blob_size: %" PRIu64 ", key_size: %" ROCKSDB_PRIszt
", read %" ROCKSDB_PRIszt " bytes, expected %" PRIu64 " bytes",
file_number, offset, size, key.size(), blob_record.size(), record_size);
return Status::Corruption("Failed to retrieve blob from blob index.");
}
Slice crc_slice(blob_record.data(), sizeof(uint32_t));
Slice blob_value(blob_record.data() + sizeof(uint32_t) + key.size(),
static_cast<size_t>(size));
uint32_t crc_exp = 0;
if (!GetFixed32(&crc_slice, &crc_exp)) {
ROCKS_LOG_DEBUG(
db_options_.info_log,
"Unable to decode CRC from blob file %" PRIu64 ", blob_offset: %" PRIu64
", blob_size: %" PRIu64 ", key size: %" ROCKSDB_PRIszt ", status: '%s'",
file_number, offset, size, key.size(), s.ToString().c_str());
return Status::Corruption("Unable to decode checksum.");
}
uint32_t crc = crc32c::Value(blob_record.data() + sizeof(uint32_t),
blob_record.size() - sizeof(uint32_t));
crc = crc32c::Mask(crc); // Adjust for storage
if (crc != crc_exp) {
if (debug_level_ >= 2) {
ROCKS_LOG_ERROR(
db_options_.info_log,
"Blob crc mismatch file: %" PRIu64 " blob_offset: %" PRIu64
" blob_size: %" PRIu64 " key: %s status: '%s'",
file_number, offset, size,
key.ToString(/* output_hex */ true).c_str(), s.ToString().c_str());
}
return Status::Corruption("Corruption. Blob CRC mismatch");
}
value->PinSelf(blob_value);
return Status::OK();
}
Status BlobDBImpl::Get(const ReadOptions& read_options,
ColumnFamilyHandle* column_family, const Slice& key,
PinnableSlice* value) {
return Get(read_options, column_family, key, value,
static_cast<uint64_t*>(nullptr) /*expiration*/);
}
Status BlobDBImpl::Get(const ReadOptions& read_options,
ColumnFamilyHandle* column_family, const Slice& key,
PinnableSlice* value, uint64_t* expiration) {
StopWatch get_sw(clock_, statistics_, BLOB_DB_GET_MICROS);
RecordTick(statistics_, BLOB_DB_NUM_GET);
return GetImpl(read_options, column_family, key, value, expiration);
}
Status BlobDBImpl::GetImpl(const ReadOptions& read_options,
ColumnFamilyHandle* column_family, const Slice& key,
PinnableSlice* value, uint64_t* expiration) {
if (column_family->GetID() != DefaultColumnFamily()->GetID()) {
return Status::NotSupported(
"Blob DB doesn't support non-default column family.");
}
// Get a snapshot to avoid blob file get deleted between we
// fetch and index entry and reading from the file.
// TODO(yiwu): For Get() retry if file not found would be a simpler strategy.
ReadOptions ro(read_options);
bool snapshot_created = SetSnapshotIfNeeded(&ro);
PinnableSlice index_entry;
Status s;
bool is_blob_index = false;
DBImpl::GetImplOptions get_impl_options;
get_impl_options.column_family = column_family;
get_impl_options.value = &index_entry;
get_impl_options.is_blob_index = &is_blob_index;
s = db_impl_->GetImpl(ro, key, get_impl_options);
if (expiration != nullptr) {
*expiration = kNoExpiration;
}
RecordTick(statistics_, BLOB_DB_NUM_KEYS_READ);
if (s.ok()) {
if (is_blob_index) {
s = GetBlobValue(key, index_entry, value, expiration);
} else {
// The index entry is the value itself in this case.
value->PinSelf(index_entry);
}
RecordTick(statistics_, BLOB_DB_BYTES_READ, value->size());
}
if (snapshot_created) {
db_->ReleaseSnapshot(ro.snapshot);
}
return s;
}
std::pair<bool, int64_t> BlobDBImpl::SanityCheck(bool aborted) {
if (aborted) {
return std::make_pair(false, -1);
}
ReadLock rl(&mutex_);
ROCKS_LOG_INFO(db_options_.info_log, "Starting Sanity Check");
ROCKS_LOG_INFO(db_options_.info_log, "Number of files %" ROCKSDB_PRIszt,
blob_files_.size());
ROCKS_LOG_INFO(db_options_.info_log, "Number of open files %" ROCKSDB_PRIszt,
open_ttl_files_.size());
for (const auto& blob_file : open_ttl_files_) {
(void)blob_file;
assert(!blob_file->Immutable());
}
for (const auto& pair : live_imm_non_ttl_blob_files_) {
const auto& blob_file = pair.second;
(void)blob_file;
assert(!blob_file->HasTTL());
assert(blob_file->Immutable());
}
uint64_t now = EpochNow();
for (auto blob_file_pair : blob_files_) {
auto blob_file = blob_file_pair.second;
std::ostringstream buf;
buf << "Blob file " << blob_file->BlobFileNumber() << ", size "
<< blob_file->GetFileSize() << ", blob count " << blob_file->BlobCount()
<< ", immutable " << blob_file->Immutable();
if (blob_file->HasTTL()) {
ExpirationRange expiration_range;
{
ReadLock file_lock(&blob_file->mutex_);
expiration_range = blob_file->GetExpirationRange();
}
buf << ", expiration range (" << expiration_range.first << ", "
<< expiration_range.second << ")";
if (!blob_file->Obsolete()) {
buf << ", expire in " << (expiration_range.second - now) << "seconds";
}
}
if (blob_file->Obsolete()) {
buf << ", obsolete at " << blob_file->GetObsoleteSequence();
}
buf << ".";
ROCKS_LOG_INFO(db_options_.info_log, "%s", buf.str().c_str());
}
// reschedule
return std::make_pair(true, -1);
}
Status BlobDBImpl::CloseBlobFile(std::shared_ptr<BlobFile> bfile) {
TEST_SYNC_POINT("BlobDBImpl::CloseBlobFile");
assert(bfile);
assert(!bfile->Immutable());
assert(!bfile->Obsolete());
if (bfile->HasTTL() || bfile == open_non_ttl_file_) {
write_mutex_.AssertHeld();
}
ROCKS_LOG_INFO(db_options_.info_log,
"Closing blob file %" PRIu64 ". Path: %s",
bfile->BlobFileNumber(), bfile->PathName().c_str());
const SequenceNumber sequence = GetLatestSequenceNumber();
const Status s = bfile->WriteFooterAndCloseLocked(sequence);
if (s.ok()) {
total_blob_size_ += BlobLogFooter::kSize;
} else {
bfile->MarkImmutable(sequence);
ROCKS_LOG_ERROR(db_options_.info_log,
"Failed to close blob file %" PRIu64 "with error: %s",
bfile->BlobFileNumber(), s.ToString().c_str());
}
if (bfile->HasTTL()) {
size_t erased __attribute__((__unused__));
erased = open_ttl_files_.erase(bfile);
} else {
if (bfile == open_non_ttl_file_) {
open_non_ttl_file_ = nullptr;
}
const uint64_t blob_file_number = bfile->BlobFileNumber();
auto it = live_imm_non_ttl_blob_files_.lower_bound(blob_file_number);
assert(it == live_imm_non_ttl_blob_files_.end() ||
it->first != blob_file_number);
live_imm_non_ttl_blob_files_.insert(
it, std::map<uint64_t, std::shared_ptr<BlobFile>>::value_type(
blob_file_number, bfile));
}
return s;
}
Status BlobDBImpl::CloseBlobFileIfNeeded(std::shared_ptr<BlobFile>& bfile) {
write_mutex_.AssertHeld();
// atomic read
if (bfile->GetFileSize() < bdb_options_.blob_file_size) {
return Status::OK();
}
WriteLock lock(&mutex_);
WriteLock file_lock(&bfile->mutex_);
assert(!bfile->Obsolete() || bfile->Immutable());
if (bfile->Immutable()) {
return Status::OK();
}
return CloseBlobFile(bfile);
}
void BlobDBImpl::ObsoleteBlobFile(std::shared_ptr<BlobFile> blob_file,
SequenceNumber obsolete_seq,
bool update_size) {
assert(blob_file->Immutable());
assert(!blob_file->Obsolete());
// Should hold write lock of mutex_ or during DB open.
blob_file->MarkObsolete(obsolete_seq);
obsolete_files_.push_back(blob_file);
assert(total_blob_size_.load() >= blob_file->GetFileSize());
if (update_size) {
total_blob_size_ -= blob_file->GetFileSize();
}
}
bool BlobDBImpl::VisibleToActiveSnapshot(
const std::shared_ptr<BlobFile>& bfile) {
assert(bfile->Obsolete());
// We check whether the oldest snapshot is no less than the last sequence
// by the time the blob file become obsolete. If so, the blob file is not
// visible to all existing snapshots.
//
// If we keep track of the earliest sequence of the keys in the blob file,
// we could instead check if there's a snapshot falls in range
// [earliest_sequence, obsolete_sequence). But doing so will make the
// implementation more complicated.
SequenceNumber obsolete_sequence = bfile->GetObsoleteSequence();
SequenceNumber oldest_snapshot = kMaxSequenceNumber;
{
// Need to lock DBImpl mutex before access snapshot list.
InstrumentedMutexLock l(db_impl_->mutex());
auto& snapshots = db_impl_->snapshots();
if (!snapshots.empty()) {
oldest_snapshot = snapshots.oldest()->GetSequenceNumber();
}
}
bool visible = oldest_snapshot < obsolete_sequence;
if (visible) {
ROCKS_LOG_INFO(db_options_.info_log,
"Obsolete blob file %" PRIu64 " (obsolete at %" PRIu64
") visible to oldest snapshot %" PRIu64 ".",
bfile->BlobFileNumber(), obsolete_sequence, oldest_snapshot);
}
return visible;
}
std::pair<bool, int64_t> BlobDBImpl::EvictExpiredFiles(bool aborted) {
if (aborted) {
return std::make_pair(false, -1);
}
TEST_SYNC_POINT("BlobDBImpl::EvictExpiredFiles:0");
TEST_SYNC_POINT("BlobDBImpl::EvictExpiredFiles:1");
std::vector<std::shared_ptr<BlobFile>> process_files;
uint64_t now = EpochNow();
{
ReadLock rl(&mutex_);
for (auto p : blob_files_) {
auto& blob_file = p.second;
ReadLock file_lock(&blob_file->mutex_);
if (blob_file->HasTTL() && !blob_file->Obsolete() &&
blob_file->GetExpirationRange().second <= now) {
process_files.push_back(blob_file);
}
}
}
TEST_SYNC_POINT("BlobDBImpl::EvictExpiredFiles:2");
TEST_SYNC_POINT("BlobDBImpl::EvictExpiredFiles:3");
TEST_SYNC_POINT_CALLBACK("BlobDBImpl::EvictExpiredFiles:cb", nullptr);
SequenceNumber seq = GetLatestSequenceNumber();
{
MutexLock l(&write_mutex_);
WriteLock lock(&mutex_);
for (auto& blob_file : process_files) {
WriteLock file_lock(&blob_file->mutex_);
// Need to double check if the file is obsolete.
if (blob_file->Obsolete()) {
assert(blob_file->Immutable());
continue;
}
if (!blob_file->Immutable()) {
CloseBlobFile(blob_file);
}
assert(blob_file->Immutable());
ObsoleteBlobFile(blob_file, seq, true /*update_size*/);
}
}
return std::make_pair(true, -1);
}
Status BlobDBImpl::SyncBlobFiles() {
MutexLock l(&write_mutex_);
std::vector<std::shared_ptr<BlobFile>> process_files;
{
ReadLock rl(&mutex_);
for (auto fitr : open_ttl_files_) {
process_files.push_back(fitr);
}
if (open_non_ttl_file_ != nullptr) {
process_files.push_back(open_non_ttl_file_);
}
}
Status s;
for (auto& blob_file : process_files) {
s = blob_file->Fsync();
if (!s.ok()) {
ROCKS_LOG_ERROR(db_options_.info_log,
"Failed to sync blob file %" PRIu64 ", status: %s",
blob_file->BlobFileNumber(), s.ToString().c_str());
return s;
}
}
s = dir_ent_->FsyncWithDirOptions(IOOptions(), nullptr, DirFsyncOptions());
if (!s.ok()) {
ROCKS_LOG_ERROR(db_options_.info_log,
"Failed to sync blob directory, status: %s",
s.ToString().c_str());
}
return s;
}
std::pair<bool, int64_t> BlobDBImpl::ReclaimOpenFiles(bool aborted) {
if (aborted) return std::make_pair(false, -1);
if (open_file_count_.load() < kOpenFilesTrigger) {
return std::make_pair(true, -1);
}
// in the future, we should sort by last_access_
// instead of closing every file
ReadLock rl(&mutex_);
for (auto const& ent : blob_files_) {
auto bfile = ent.second;
if (bfile->last_access_.load() == -1) continue;
WriteLock lockbfile_w(&bfile->mutex_);
CloseRandomAccessLocked(bfile);
}
return std::make_pair(true, -1);
}
std::pair<bool, int64_t> BlobDBImpl::DeleteObsoleteFiles(bool aborted) {
if (aborted) {
return std::make_pair(false, -1);
}
MutexLock delete_file_lock(&delete_file_mutex_);
if (disable_file_deletions_ > 0) {
return std::make_pair(true, -1);
}
std::list<std::shared_ptr<BlobFile>> tobsolete;
{
WriteLock wl(&mutex_);
if (obsolete_files_.empty()) {
return std::make_pair(true, -1);
}
tobsolete.swap(obsolete_files_);
}
bool file_deleted = false;
for (auto iter = tobsolete.begin(); iter != tobsolete.end();) {
auto bfile = *iter;
{
ReadLock lockbfile_r(&bfile->mutex_);
if (VisibleToActiveSnapshot(bfile)) {
ROCKS_LOG_INFO(db_options_.info_log,
"Could not delete file due to snapshot failure %s",
bfile->PathName().c_str());
++iter;
continue;
}
}
ROCKS_LOG_INFO(db_options_.info_log,
"Will delete file due to snapshot success %s",
bfile->PathName().c_str());
{
WriteLock wl(&mutex_);
blob_files_.erase(bfile->BlobFileNumber());
}
Status s = DeleteDBFile(&(db_impl_->immutable_db_options()),
bfile->PathName(), blob_dir_, true,
/*force_fg=*/false);
if (!s.ok()) {
ROCKS_LOG_ERROR(db_options_.info_log,
"File failed to be deleted as obsolete %s",
bfile->PathName().c_str());
++iter;
continue;
}
file_deleted = true;
ROCKS_LOG_INFO(db_options_.info_log,
"File deleted as obsolete from blob dir %s",
bfile->PathName().c_str());
iter = tobsolete.erase(iter);
}
// directory change. Fsync
if (file_deleted) {
Status s = dir_ent_->FsyncWithDirOptions(
IOOptions(), nullptr,
DirFsyncOptions(DirFsyncOptions::FsyncReason::kFileDeleted));
if (!s.ok()) {
ROCKS_LOG_ERROR(db_options_.info_log, "Failed to sync dir %s: %s",
blob_dir_.c_str(), s.ToString().c_str());
}
}
// put files back into obsolete if for some reason, delete failed
if (!tobsolete.empty()) {
WriteLock wl(&mutex_);
for (auto bfile : tobsolete) {
blob_files_.insert(std::make_pair(bfile->BlobFileNumber(), bfile));
obsolete_files_.push_front(bfile);
}
}
return std::make_pair(!aborted, -1);
}
void BlobDBImpl::CopyBlobFiles(
std::vector<std::shared_ptr<BlobFile>>* bfiles_copy) {
ReadLock rl(&mutex_);
for (auto const& p : blob_files_) {
bfiles_copy->push_back(p.second);
}
}
Iterator* BlobDBImpl::NewIterator(const ReadOptions& read_options) {
auto* cfd =
static_cast_with_check<ColumnFamilyHandleImpl>(DefaultColumnFamily())
->cfd();
// Get a snapshot to avoid blob file get deleted between we
// fetch and index entry and reading from the file.
ManagedSnapshot* own_snapshot = nullptr;
const Snapshot* snapshot = read_options.snapshot;
if (snapshot == nullptr) {
own_snapshot = new ManagedSnapshot(db_);
snapshot = own_snapshot->snapshot();
}
auto* iter = db_impl_->NewIteratorImpl(
read_options, cfd, snapshot->GetSequenceNumber(),
nullptr /*read_callback*/, true /*expose_blob_index*/);
return new BlobDBIterator(own_snapshot, iter, this, clock_, statistics_);
}
Status DestroyBlobDB(const std::string& dbname, const Options& options,
const BlobDBOptions& bdb_options) {
const ImmutableDBOptions soptions(SanitizeOptions(dbname, options));
Env* env = soptions.env;
Status status;
std::string blobdir;
blobdir = (bdb_options.path_relative) ? dbname + "/" + bdb_options.blob_dir
: bdb_options.blob_dir;
std::vector<std::string> filenames;
if (env->GetChildren(blobdir, &filenames).ok()) {
for (const auto& f : filenames) {
uint64_t number;
FileType type;
if (ParseFileName(f, &number, &type) && type == kBlobFile) {
Status del = DeleteDBFile(&soptions, blobdir + "/" + f, blobdir, true,
/*force_fg=*/false);
if (status.ok() && !del.ok()) {
status = del;
}
}
}
// TODO: What to do if we cannot delete the directory?
env->DeleteDir(blobdir).PermitUncheckedError();
}
Status destroy = DestroyDB(dbname, options);
if (status.ok() && !destroy.ok()) {
status = destroy;
}
return status;
}
#ifndef NDEBUG
Status BlobDBImpl::TEST_GetBlobValue(const Slice& key, const Slice& index_entry,
PinnableSlice* value) {
return GetBlobValue(key, index_entry, value);
}
void BlobDBImpl::TEST_AddDummyBlobFile(uint64_t blob_file_number,
SequenceNumber immutable_sequence) {
auto blob_file = std::make_shared<BlobFile>(this, blob_dir_, blob_file_number,
db_options_.info_log.get());
blob_file->MarkImmutable(immutable_sequence);
blob_files_[blob_file_number] = blob_file;
live_imm_non_ttl_blob_files_[blob_file_number] = blob_file;
}
std::vector<std::shared_ptr<BlobFile>> BlobDBImpl::TEST_GetBlobFiles() const {
ReadLock l(&mutex_);
std::vector<std::shared_ptr<BlobFile>> blob_files;
for (auto& p : blob_files_) {
blob_files.emplace_back(p.second);
}
return blob_files;
}
std::vector<std::shared_ptr<BlobFile>> BlobDBImpl::TEST_GetLiveImmNonTTLFiles()
const {
ReadLock l(&mutex_);
std::vector<std::shared_ptr<BlobFile>> live_imm_non_ttl_files;
for (const auto& pair : live_imm_non_ttl_blob_files_) {
live_imm_non_ttl_files.emplace_back(pair.second);
}
return live_imm_non_ttl_files;
}
std::vector<std::shared_ptr<BlobFile>> BlobDBImpl::TEST_GetObsoleteFiles()
const {
ReadLock l(&mutex_);
std::vector<std::shared_ptr<BlobFile>> obsolete_files;
for (auto& bfile : obsolete_files_) {
obsolete_files.emplace_back(bfile);
}
return obsolete_files;
}
void BlobDBImpl::TEST_DeleteObsoleteFiles() {
DeleteObsoleteFiles(false /*abort*/);
}
Status BlobDBImpl::TEST_CloseBlobFile(std::shared_ptr<BlobFile>& bfile) {
MutexLock l(&write_mutex_);
WriteLock lock(&mutex_);
WriteLock file_lock(&bfile->mutex_);
return CloseBlobFile(bfile);
}
void BlobDBImpl::TEST_ObsoleteBlobFile(std::shared_ptr<BlobFile>& blob_file,
SequenceNumber obsolete_seq,
bool update_size) {
return ObsoleteBlobFile(blob_file, obsolete_seq, update_size);
}
void BlobDBImpl::TEST_EvictExpiredFiles() {
EvictExpiredFiles(false /*abort*/);
}
uint64_t BlobDBImpl::TEST_live_sst_size() { return live_sst_size_.load(); }
void BlobDBImpl::TEST_InitializeBlobFileToSstMapping(
const std::vector<LiveFileMetaData>& live_files) {
InitializeBlobFileToSstMapping(live_files);
}
void BlobDBImpl::TEST_ProcessFlushJobInfo(const FlushJobInfo& info) {
ProcessFlushJobInfo(info);
}
void BlobDBImpl::TEST_ProcessCompactionJobInfo(const CompactionJobInfo& info) {
ProcessCompactionJobInfo(info);
}
#endif // !NDEBUG
} // namespace blob_db
} // namespace ROCKSDB_NAMESPACE
#endif // ROCKSDB_LITE
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