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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:45:59 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:45:59 +0000 |
commit | 19fcec84d8d7d21e796c7624e521b60d28ee21ed (patch) | |
tree | 42d26aa27d1e3f7c0b8bd3fd14e7d7082f5008dc /src/rocksdb/db/db_impl/db_impl_files.cc | |
parent | Initial commit. (diff) | |
download | ceph-19fcec84d8d7d21e796c7624e521b60d28ee21ed.tar.xz ceph-19fcec84d8d7d21e796c7624e521b60d28ee21ed.zip |
Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/rocksdb/db/db_impl/db_impl_files.cc')
-rw-r--r-- | src/rocksdb/db/db_impl/db_impl_files.cc | 667 |
1 files changed, 667 insertions, 0 deletions
diff --git a/src/rocksdb/db/db_impl/db_impl_files.cc b/src/rocksdb/db/db_impl/db_impl_files.cc new file mode 100644 index 000000000..c5d07dd01 --- /dev/null +++ b/src/rocksdb/db/db_impl/db_impl_files.cc @@ -0,0 +1,667 @@ +// 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. +#include "db/db_impl/db_impl.h" + +#include <cinttypes> +#include <set> +#include <unordered_set> +#include "db/event_helpers.h" +#include "db/memtable_list.h" +#include "file/file_util.h" +#include "file/sst_file_manager_impl.h" +#include "util/autovector.h" + +namespace ROCKSDB_NAMESPACE { + +uint64_t DBImpl::MinLogNumberToKeep() { + if (allow_2pc()) { + return versions_->min_log_number_to_keep_2pc(); + } else { + return versions_->MinLogNumberWithUnflushedData(); + } +} + +uint64_t DBImpl::MinObsoleteSstNumberToKeep() { + mutex_.AssertHeld(); + if (!pending_outputs_.empty()) { + return *pending_outputs_.begin(); + } + return std::numeric_limits<uint64_t>::max(); +} + +// * Returns the list of live files in 'sst_live' +// If it's doing full scan: +// * Returns the list of all files in the filesystem in +// 'full_scan_candidate_files'. +// Otherwise, gets obsolete files from VersionSet. +// no_full_scan = true -- never do the full scan using GetChildren() +// force = false -- don't force the full scan, except every +// mutable_db_options_.delete_obsolete_files_period_micros +// force = true -- force the full scan +void DBImpl::FindObsoleteFiles(JobContext* job_context, bool force, + bool no_full_scan) { + mutex_.AssertHeld(); + + // if deletion is disabled, do nothing + if (disable_delete_obsolete_files_ > 0) { + return; + } + + bool doing_the_full_scan = false; + + // logic for figuring out if we're doing the full scan + if (no_full_scan) { + doing_the_full_scan = false; + } else if (force || + mutable_db_options_.delete_obsolete_files_period_micros == 0) { + doing_the_full_scan = true; + } else { + const uint64_t now_micros = env_->NowMicros(); + if ((delete_obsolete_files_last_run_ + + mutable_db_options_.delete_obsolete_files_period_micros) < + now_micros) { + doing_the_full_scan = true; + delete_obsolete_files_last_run_ = now_micros; + } + } + + // don't delete files that might be currently written to from compaction + // threads + // Since job_context->min_pending_output is set, until file scan finishes, + // mutex_ cannot be released. Otherwise, we might see no min_pending_output + // here but later find newer generated unfinalized files while scanning. + if (!pending_outputs_.empty()) { + job_context->min_pending_output = *pending_outputs_.begin(); + } else { + // delete all of them + job_context->min_pending_output = std::numeric_limits<uint64_t>::max(); + } + + // Get obsolete files. This function will also update the list of + // pending files in VersionSet(). + versions_->GetObsoleteFiles(&job_context->sst_delete_files, + &job_context->manifest_delete_files, + job_context->min_pending_output); + + // Mark the elements in job_context->sst_delete_files as grabbedForPurge + // so that other threads calling FindObsoleteFiles with full_scan=true + // will not add these files to candidate list for purge. + for (const auto& sst_to_del : job_context->sst_delete_files) { + MarkAsGrabbedForPurge(sst_to_del.metadata->fd.GetNumber()); + } + + // store the current filenum, lognum, etc + job_context->manifest_file_number = versions_->manifest_file_number(); + job_context->pending_manifest_file_number = + versions_->pending_manifest_file_number(); + job_context->log_number = MinLogNumberToKeep(); + job_context->prev_log_number = versions_->prev_log_number(); + + versions_->AddLiveFiles(&job_context->sst_live); + if (doing_the_full_scan) { + InfoLogPrefix info_log_prefix(!immutable_db_options_.db_log_dir.empty(), + dbname_); + std::set<std::string> paths; + for (size_t path_id = 0; path_id < immutable_db_options_.db_paths.size(); + path_id++) { + paths.insert(immutable_db_options_.db_paths[path_id].path); + } + + // Note that if cf_paths is not specified in the ColumnFamilyOptions + // of a particular column family, we use db_paths as the cf_paths + // setting. Hence, there can be multiple duplicates of files from db_paths + // in the following code. The duplicate are removed while identifying + // unique files in PurgeObsoleteFiles. + for (auto cfd : *versions_->GetColumnFamilySet()) { + for (size_t path_id = 0; path_id < cfd->ioptions()->cf_paths.size(); + path_id++) { + auto& path = cfd->ioptions()->cf_paths[path_id].path; + + if (paths.find(path) == paths.end()) { + paths.insert(path); + } + } + } + + for (auto& path : paths) { + // set of all files in the directory. We'll exclude files that are still + // alive in the subsequent processings. + std::vector<std::string> files; + env_->GetChildren(path, &files); // Ignore errors + for (const std::string& file : files) { + uint64_t number; + FileType type; + // 1. If we cannot parse the file name, we skip; + // 2. If the file with file_number equals number has already been + // grabbed for purge by another compaction job, or it has already been + // schedule for purge, we also skip it if we + // are doing full scan in order to avoid double deletion of the same + // file under race conditions. See + // https://github.com/facebook/rocksdb/issues/3573 + if (!ParseFileName(file, &number, info_log_prefix.prefix, &type) || + !ShouldPurge(number)) { + continue; + } + + // TODO(icanadi) clean up this mess to avoid having one-off "/" prefixes + job_context->full_scan_candidate_files.emplace_back("/" + file, path); + } + } + + // Add log files in wal_dir + if (immutable_db_options_.wal_dir != dbname_) { + std::vector<std::string> log_files; + env_->GetChildren(immutable_db_options_.wal_dir, + &log_files); // Ignore errors + for (const std::string& log_file : log_files) { + job_context->full_scan_candidate_files.emplace_back( + log_file, immutable_db_options_.wal_dir); + } + } + // Add info log files in db_log_dir + if (!immutable_db_options_.db_log_dir.empty() && + immutable_db_options_.db_log_dir != dbname_) { + std::vector<std::string> info_log_files; + // Ignore errors + env_->GetChildren(immutable_db_options_.db_log_dir, &info_log_files); + for (std::string& log_file : info_log_files) { + job_context->full_scan_candidate_files.emplace_back( + log_file, immutable_db_options_.db_log_dir); + } + } + } + + // logs_ is empty when called during recovery, in which case there can't yet + // be any tracked obsolete logs + if (!alive_log_files_.empty() && !logs_.empty()) { + uint64_t min_log_number = job_context->log_number; + size_t num_alive_log_files = alive_log_files_.size(); + // find newly obsoleted log files + while (alive_log_files_.begin()->number < min_log_number) { + auto& earliest = *alive_log_files_.begin(); + if (immutable_db_options_.recycle_log_file_num > + log_recycle_files_.size()) { + ROCKS_LOG_INFO(immutable_db_options_.info_log, + "adding log %" PRIu64 " to recycle list\n", + earliest.number); + log_recycle_files_.push_back(earliest.number); + } else { + job_context->log_delete_files.push_back(earliest.number); + } + if (job_context->size_log_to_delete == 0) { + job_context->prev_total_log_size = total_log_size_; + job_context->num_alive_log_files = num_alive_log_files; + } + job_context->size_log_to_delete += earliest.size; + total_log_size_ -= earliest.size; + if (two_write_queues_) { + log_write_mutex_.Lock(); + } + alive_log_files_.pop_front(); + if (two_write_queues_) { + log_write_mutex_.Unlock(); + } + // Current log should always stay alive since it can't have + // number < MinLogNumber(). + assert(alive_log_files_.size()); + } + while (!logs_.empty() && logs_.front().number < min_log_number) { + auto& log = logs_.front(); + if (log.getting_synced) { + log_sync_cv_.Wait(); + // logs_ could have changed while we were waiting. + continue; + } + logs_to_free_.push_back(log.ReleaseWriter()); + { + InstrumentedMutexLock wl(&log_write_mutex_); + logs_.pop_front(); + } + } + // Current log cannot be obsolete. + assert(!logs_.empty()); + } + + // We're just cleaning up for DB::Write(). + assert(job_context->logs_to_free.empty()); + job_context->logs_to_free = logs_to_free_; + job_context->log_recycle_files.assign(log_recycle_files_.begin(), + log_recycle_files_.end()); + if (job_context->HaveSomethingToDelete()) { + ++pending_purge_obsolete_files_; + } + logs_to_free_.clear(); +} + +namespace { +bool CompareCandidateFile(const JobContext::CandidateFileInfo& first, + const JobContext::CandidateFileInfo& second) { + if (first.file_name > second.file_name) { + return true; + } else if (first.file_name < second.file_name) { + return false; + } else { + return (first.file_path > second.file_path); + } +} +}; // namespace + +// Delete obsolete files and log status and information of file deletion +void DBImpl::DeleteObsoleteFileImpl(int job_id, const std::string& fname, + const std::string& path_to_sync, + FileType type, uint64_t number) { + Status file_deletion_status; + if (type == kTableFile || type == kLogFile) { + file_deletion_status = + DeleteDBFile(&immutable_db_options_, fname, path_to_sync, + /*force_bg=*/false, /*force_fg=*/!wal_in_db_path_); + } else { + file_deletion_status = env_->DeleteFile(fname); + } + TEST_SYNC_POINT_CALLBACK("DBImpl::DeleteObsoleteFileImpl:AfterDeletion", + &file_deletion_status); + if (file_deletion_status.ok()) { + ROCKS_LOG_DEBUG(immutable_db_options_.info_log, + "[JOB %d] Delete %s type=%d #%" PRIu64 " -- %s\n", job_id, + fname.c_str(), type, number, + file_deletion_status.ToString().c_str()); + } else if (env_->FileExists(fname).IsNotFound()) { + ROCKS_LOG_INFO( + immutable_db_options_.info_log, + "[JOB %d] Tried to delete a non-existing file %s type=%d #%" PRIu64 + " -- %s\n", + job_id, fname.c_str(), type, number, + file_deletion_status.ToString().c_str()); + } else { + ROCKS_LOG_ERROR(immutable_db_options_.info_log, + "[JOB %d] Failed to delete %s type=%d #%" PRIu64 " -- %s\n", + job_id, fname.c_str(), type, number, + file_deletion_status.ToString().c_str()); + } + if (type == kTableFile) { + EventHelpers::LogAndNotifyTableFileDeletion( + &event_logger_, job_id, number, fname, file_deletion_status, GetName(), + immutable_db_options_.listeners); + } +} + +// Diffs the files listed in filenames and those that do not +// belong to live files are possibly removed. Also, removes all the +// files in sst_delete_files and log_delete_files. +// It is not necessary to hold the mutex when invoking this method. +void DBImpl::PurgeObsoleteFiles(JobContext& state, bool schedule_only) { + TEST_SYNC_POINT("DBImpl::PurgeObsoleteFiles:Begin"); + // we'd better have sth to delete + assert(state.HaveSomethingToDelete()); + + // FindObsoleteFiles() should've populated this so nonzero + assert(state.manifest_file_number != 0); + + // Now, convert live list to an unordered map, WITHOUT mutex held; + // set is slow. + std::unordered_map<uint64_t, const FileDescriptor*> sst_live_map; + for (const FileDescriptor& fd : state.sst_live) { + sst_live_map[fd.GetNumber()] = &fd; + } + std::unordered_set<uint64_t> log_recycle_files_set( + state.log_recycle_files.begin(), state.log_recycle_files.end()); + + auto candidate_files = state.full_scan_candidate_files; + candidate_files.reserve( + candidate_files.size() + state.sst_delete_files.size() + + state.log_delete_files.size() + state.manifest_delete_files.size()); + // We may ignore the dbname when generating the file names. + for (auto& file : state.sst_delete_files) { + candidate_files.emplace_back( + MakeTableFileName(file.metadata->fd.GetNumber()), file.path); + if (file.metadata->table_reader_handle) { + table_cache_->Release(file.metadata->table_reader_handle); + } + file.DeleteMetadata(); + } + + for (auto file_num : state.log_delete_files) { + if (file_num > 0) { + candidate_files.emplace_back(LogFileName(file_num), + immutable_db_options_.wal_dir); + } + } + for (const auto& filename : state.manifest_delete_files) { + candidate_files.emplace_back(filename, dbname_); + } + + // dedup state.candidate_files so we don't try to delete the same + // file twice + std::sort(candidate_files.begin(), candidate_files.end(), + CompareCandidateFile); + candidate_files.erase( + std::unique(candidate_files.begin(), candidate_files.end()), + candidate_files.end()); + + if (state.prev_total_log_size > 0) { + ROCKS_LOG_INFO(immutable_db_options_.info_log, + "[JOB %d] Try to delete WAL files size %" PRIu64 + ", prev total WAL file size %" PRIu64 + ", number of live WAL files %" ROCKSDB_PRIszt ".\n", + state.job_id, state.size_log_to_delete, + state.prev_total_log_size, state.num_alive_log_files); + } + + std::vector<std::string> old_info_log_files; + InfoLogPrefix info_log_prefix(!immutable_db_options_.db_log_dir.empty(), + dbname_); + + // File numbers of most recent two OPTIONS file in candidate_files (found in + // previos FindObsoleteFiles(full_scan=true)) + // At this point, there must not be any duplicate file numbers in + // candidate_files. + uint64_t optsfile_num1 = std::numeric_limits<uint64_t>::min(); + uint64_t optsfile_num2 = std::numeric_limits<uint64_t>::min(); + for (const auto& candidate_file : candidate_files) { + const std::string& fname = candidate_file.file_name; + uint64_t number; + FileType type; + if (!ParseFileName(fname, &number, info_log_prefix.prefix, &type) || + type != kOptionsFile) { + continue; + } + if (number > optsfile_num1) { + optsfile_num2 = optsfile_num1; + optsfile_num1 = number; + } else if (number > optsfile_num2) { + optsfile_num2 = number; + } + } + + // Close WALs before trying to delete them. + for (const auto w : state.logs_to_free) { + // TODO: maybe check the return value of Close. + w->Close(); + } + + bool own_files = OwnTablesAndLogs(); + std::unordered_set<uint64_t> files_to_del; + for (const auto& candidate_file : candidate_files) { + const std::string& to_delete = candidate_file.file_name; + uint64_t number; + FileType type; + // Ignore file if we cannot recognize it. + if (!ParseFileName(to_delete, &number, info_log_prefix.prefix, &type)) { + continue; + } + + bool keep = true; + switch (type) { + case kLogFile: + keep = ((number >= state.log_number) || + (number == state.prev_log_number) || + (log_recycle_files_set.find(number) != + log_recycle_files_set.end())); + break; + case kDescriptorFile: + // Keep my manifest file, and any newer incarnations' + // (can happen during manifest roll) + keep = (number >= state.manifest_file_number); + break; + case kTableFile: + // If the second condition is not there, this makes + // DontDeletePendingOutputs fail + keep = (sst_live_map.find(number) != sst_live_map.end()) || + number >= state.min_pending_output; + if (!keep) { + files_to_del.insert(number); + } + break; + case kTempFile: + // Any temp files that are currently being written to must + // be recorded in pending_outputs_, which is inserted into "live". + // Also, SetCurrentFile creates a temp file when writing out new + // manifest, which is equal to state.pending_manifest_file_number. We + // should not delete that file + // + // TODO(yhchiang): carefully modify the third condition to safely + // remove the temp options files. + keep = (sst_live_map.find(number) != sst_live_map.end()) || + (number == state.pending_manifest_file_number) || + (to_delete.find(kOptionsFileNamePrefix) != std::string::npos); + break; + case kInfoLogFile: + keep = true; + if (number != 0) { + old_info_log_files.push_back(to_delete); + } + break; + case kOptionsFile: + keep = (number >= optsfile_num2); + TEST_SYNC_POINT_CALLBACK( + "DBImpl::PurgeObsoleteFiles:CheckOptionsFiles:1", + reinterpret_cast<void*>(&number)); + TEST_SYNC_POINT_CALLBACK( + "DBImpl::PurgeObsoleteFiles:CheckOptionsFiles:2", + reinterpret_cast<void*>(&keep)); + break; + case kCurrentFile: + case kDBLockFile: + case kIdentityFile: + case kMetaDatabase: + case kBlobFile: + keep = true; + break; + } + + if (keep) { + continue; + } + + std::string fname; + std::string dir_to_sync; + if (type == kTableFile) { + // evict from cache + TableCache::Evict(table_cache_.get(), number); + fname = MakeTableFileName(candidate_file.file_path, number); + dir_to_sync = candidate_file.file_path; + } else { + dir_to_sync = + (type == kLogFile) ? immutable_db_options_.wal_dir : dbname_; + fname = dir_to_sync + + ((!dir_to_sync.empty() && dir_to_sync.back() == '/') || + (!to_delete.empty() && to_delete.front() == '/') + ? "" + : "/") + + to_delete; + } + +#ifndef ROCKSDB_LITE + if (type == kLogFile && (immutable_db_options_.wal_ttl_seconds > 0 || + immutable_db_options_.wal_size_limit_mb > 0)) { + wal_manager_.ArchiveWALFile(fname, number); + continue; + } +#endif // !ROCKSDB_LITE + + // If I do not own these files, e.g. secondary instance with max_open_files + // = -1, then no need to delete or schedule delete these files since they + // will be removed by their owner, e.g. the primary instance. + if (!own_files) { + continue; + } + Status file_deletion_status; + if (schedule_only) { + InstrumentedMutexLock guard_lock(&mutex_); + SchedulePendingPurge(fname, dir_to_sync, type, number, state.job_id); + } else { + DeleteObsoleteFileImpl(state.job_id, fname, dir_to_sync, type, number); + } + } + + { + // After purging obsolete files, remove them from files_grabbed_for_purge_. + InstrumentedMutexLock guard_lock(&mutex_); + autovector<uint64_t> to_be_removed; + for (auto fn : files_grabbed_for_purge_) { + if (files_to_del.count(fn) != 0) { + to_be_removed.emplace_back(fn); + } + } + for (auto fn : to_be_removed) { + files_grabbed_for_purge_.erase(fn); + } + } + + // Delete old info log files. + size_t old_info_log_file_count = old_info_log_files.size(); + if (old_info_log_file_count != 0 && + old_info_log_file_count >= immutable_db_options_.keep_log_file_num) { + std::sort(old_info_log_files.begin(), old_info_log_files.end()); + size_t end = + old_info_log_file_count - immutable_db_options_.keep_log_file_num; + for (unsigned int i = 0; i <= end; i++) { + std::string& to_delete = old_info_log_files.at(i); + std::string full_path_to_delete = + (immutable_db_options_.db_log_dir.empty() + ? dbname_ + : immutable_db_options_.db_log_dir) + + "/" + to_delete; + ROCKS_LOG_INFO(immutable_db_options_.info_log, + "[JOB %d] Delete info log file %s\n", state.job_id, + full_path_to_delete.c_str()); + Status s = env_->DeleteFile(full_path_to_delete); + if (!s.ok()) { + if (env_->FileExists(full_path_to_delete).IsNotFound()) { + ROCKS_LOG_INFO( + immutable_db_options_.info_log, + "[JOB %d] Tried to delete non-existing info log file %s FAILED " + "-- %s\n", + state.job_id, to_delete.c_str(), s.ToString().c_str()); + } else { + ROCKS_LOG_ERROR(immutable_db_options_.info_log, + "[JOB %d] Delete info log file %s FAILED -- %s\n", + state.job_id, to_delete.c_str(), + s.ToString().c_str()); + } + } + } + } +#ifndef ROCKSDB_LITE + wal_manager_.PurgeObsoleteWALFiles(); +#endif // ROCKSDB_LITE + LogFlush(immutable_db_options_.info_log); + InstrumentedMutexLock l(&mutex_); + --pending_purge_obsolete_files_; + assert(pending_purge_obsolete_files_ >= 0); + if (pending_purge_obsolete_files_ == 0) { + bg_cv_.SignalAll(); + } + TEST_SYNC_POINT("DBImpl::PurgeObsoleteFiles:End"); +} + +void DBImpl::DeleteObsoleteFiles() { + mutex_.AssertHeld(); + JobContext job_context(next_job_id_.fetch_add(1)); + FindObsoleteFiles(&job_context, true); + + mutex_.Unlock(); + if (job_context.HaveSomethingToDelete()) { + PurgeObsoleteFiles(job_context); + } + job_context.Clean(); + mutex_.Lock(); +} + +uint64_t FindMinPrepLogReferencedByMemTable( + VersionSet* vset, const ColumnFamilyData* cfd_to_flush, + const autovector<MemTable*>& memtables_to_flush) { + uint64_t min_log = 0; + + // we must look through the memtables for two phase transactions + // that have been committed but not yet flushed + for (auto loop_cfd : *vset->GetColumnFamilySet()) { + if (loop_cfd->IsDropped() || loop_cfd == cfd_to_flush) { + continue; + } + + auto log = loop_cfd->imm()->PrecomputeMinLogContainingPrepSection( + memtables_to_flush); + + if (log > 0 && (min_log == 0 || log < min_log)) { + min_log = log; + } + + log = loop_cfd->mem()->GetMinLogContainingPrepSection(); + + if (log > 0 && (min_log == 0 || log < min_log)) { + min_log = log; + } + } + + return min_log; +} + +uint64_t PrecomputeMinLogNumberToKeep( + VersionSet* vset, const ColumnFamilyData& cfd_to_flush, + autovector<VersionEdit*> edit_list, + const autovector<MemTable*>& memtables_to_flush, + LogsWithPrepTracker* prep_tracker) { + assert(vset != nullptr); + assert(prep_tracker != nullptr); + // Calculate updated min_log_number_to_keep + // Since the function should only be called in 2pc mode, log number in + // the version edit should be sufficient. + + // Precompute the min log number containing unflushed data for the column + // family being flushed (`cfd_to_flush`). + uint64_t cf_min_log_number_to_keep = 0; + for (auto& e : edit_list) { + if (e->HasLogNumber()) { + cf_min_log_number_to_keep = + std::max(cf_min_log_number_to_keep, e->GetLogNumber()); + } + } + if (cf_min_log_number_to_keep == 0) { + // No version edit contains information on log number. The log number + // for this column family should stay the same as it is. + cf_min_log_number_to_keep = cfd_to_flush.GetLogNumber(); + } + + // Get min log number containing unflushed data for other column families. + uint64_t min_log_number_to_keep = + vset->PreComputeMinLogNumberWithUnflushedData(&cfd_to_flush); + if (cf_min_log_number_to_keep != 0) { + min_log_number_to_keep = + std::min(cf_min_log_number_to_keep, min_log_number_to_keep); + } + + // if are 2pc we must consider logs containing prepared + // sections of outstanding transactions. + // + // We must check min logs with outstanding prep before we check + // logs references by memtables because a log referenced by the + // first data structure could transition to the second under us. + // + // TODO: iterating over all column families under db mutex. + // should find more optimal solution + auto min_log_in_prep_heap = + prep_tracker->FindMinLogContainingOutstandingPrep(); + + if (min_log_in_prep_heap != 0 && + min_log_in_prep_heap < min_log_number_to_keep) { + min_log_number_to_keep = min_log_in_prep_heap; + } + + uint64_t min_log_refed_by_mem = FindMinPrepLogReferencedByMemTable( + vset, &cfd_to_flush, memtables_to_flush); + + if (min_log_refed_by_mem != 0 && + min_log_refed_by_mem < min_log_number_to_keep) { + min_log_number_to_keep = min_log_refed_by_mem; + } + return min_log_number_to_keep; +} + +} // namespace ROCKSDB_NAMESPACE |