From 91bc0130fa0790a77694c4a9c352fbbaa55b9f80 Mon Sep 17 00:00:00 2001 From: Cheng Chang Date: Tue, 5 May 2020 11:07:52 -0700 Subject: [PATCH] Refactor level compaction picker (#6804) Summary: 1. refactor out PickFileToCompact to remove duplicated logic. 2. remove redundant checks of `start_level_inputs_.empty()`. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6804 Test Plan: make check Reviewed By: siying Differential Revision: D21390053 Pulled By: cheng-chang fbshipit-source-id: 185d5987a08bfdaf63f0f245310c6da69878d415 --- db/compaction/compaction_picker_level.cc | 143 ++++++++--------------- 1 file changed, 46 insertions(+), 97 deletions(-) diff --git a/db/compaction/compaction_picker_level.cc b/db/compaction/compaction_picker_level.cc index 6528c9b6021..c376aa7356b 100644 --- a/db/compaction/compaction_picker_level.cc +++ b/db/compaction/compaction_picker_level.cc @@ -93,9 +93,13 @@ class LevelCompactionBuilder { // otherwise, returns false. bool PickIntraL0Compaction(); - void PickExpiredTtlFiles(); - - void PickFilesMarkedForPeriodicCompaction(); + // Picks a file from level_files to compact. + // level_files is a vector of (level, file metadata) in ascending order of + // level. If compact_to_next_level is true, compact the file to the next + // level, otherwise, compact to the same level as the input file. + void PickFileToCompact( + const autovector>& level_files, + bool compact_to_next_level); const std::string& cf_name_; VersionStorageInfo* vstorage_; @@ -124,72 +128,34 @@ class LevelCompactionBuilder { static const int kMinFilesForIntraL0Compaction = 4; }; -void LevelCompactionBuilder::PickExpiredTtlFiles() { - if (vstorage_->ExpiredTtlFiles().empty()) { - return; - } - - auto continuation = [&](std::pair level_file) { +void LevelCompactionBuilder::PickFileToCompact( + const autovector>& level_files, + bool compact_to_next_level) { + for (auto& level_file : level_files) { // If it's being compacted it has nothing to do here. // If this assert() fails that means that some function marked some // files as being_compacted, but didn't call ComputeCompactionScore() assert(!level_file.second->being_compacted); start_level_ = level_file.first; - output_level_ = - (start_level_ == 0) ? vstorage_->base_level() : start_level_ + 1; - - if ((start_level_ == vstorage_->num_non_empty_levels() - 1) || + if ((compact_to_next_level && + start_level_ == vstorage_->num_non_empty_levels() - 1) || (start_level_ == 0 && !compaction_picker_->level0_compactions_in_progress()->empty())) { - return false; - } - - start_level_inputs_.files = {level_file.second}; - start_level_inputs_.level = start_level_; - return compaction_picker_->ExpandInputsToCleanCut(cf_name_, vstorage_, - &start_level_inputs_); - }; - - for (auto& level_file : vstorage_->ExpiredTtlFiles()) { - if (continuation(level_file)) { - // found the compaction! - return; + continue; } - } - - start_level_inputs_.files.clear(); -} - -void LevelCompactionBuilder::PickFilesMarkedForPeriodicCompaction() { - if (vstorage_->FilesMarkedForPeriodicCompaction().empty()) { - return; - } - - auto continuation = [&](std::pair level_file) { - // If it's being compacted it has nothing to do here. - // If this assert() fails that means that some function marked some - // files as being_compacted, but didn't call ComputeCompactionScore() - assert(!level_file.second->being_compacted); - output_level_ = start_level_ = level_file.first; - - if (start_level_ == 0 && - !compaction_picker_->level0_compactions_in_progress()->empty()) { - return false; + if (compact_to_next_level) { + output_level_ = + (start_level_ == 0) ? vstorage_->base_level() : start_level_ + 1; + } else { + output_level_ = start_level_; } - start_level_inputs_.files = {level_file.second}; start_level_inputs_.level = start_level_; - return compaction_picker_->ExpandInputsToCleanCut(cf_name_, vstorage_, - &start_level_inputs_); - }; - - for (auto& level_file : vstorage_->FilesMarkedForPeriodicCompaction()) { - if (continuation(level_file)) { - // found the compaction! + if (compaction_picker_->ExpandInputsToCleanCut(cf_name_, vstorage_, + &start_level_inputs_)) { return; } } - start_level_inputs_.files.clear(); } @@ -238,63 +204,46 @@ void LevelCompactionBuilder::SetupInitialFiles() { } } } + } else { + // Compaction scores are sorted in descending order, no further scores + // will be >= 1. + break; } } + if (!start_level_inputs_.empty()) { + return; + } // if we didn't find a compaction, check if there are any files marked for // compaction - if (start_level_inputs_.empty()) { - parent_index_ = base_index_ = -1; + parent_index_ = base_index_ = -1; - compaction_picker_->PickFilesMarkedForCompaction( - cf_name_, vstorage_, &start_level_, &output_level_, - &start_level_inputs_); - if (!start_level_inputs_.empty()) { - compaction_reason_ = CompactionReason::kFilesMarkedForCompaction; - return; - } + compaction_picker_->PickFilesMarkedForCompaction( + cf_name_, vstorage_, &start_level_, &output_level_, &start_level_inputs_); + if (!start_level_inputs_.empty()) { + compaction_reason_ = CompactionReason::kFilesMarkedForCompaction; + return; } // Bottommost Files Compaction on deleting tombstones - if (start_level_inputs_.empty()) { - size_t i; - for (i = 0; i < vstorage_->BottommostFilesMarkedForCompaction().size(); - ++i) { - auto& level_and_file = vstorage_->BottommostFilesMarkedForCompaction()[i]; - assert(!level_and_file.second->being_compacted); - start_level_inputs_.level = output_level_ = start_level_ = - level_and_file.first; - start_level_inputs_.files = {level_and_file.second}; - if (compaction_picker_->ExpandInputsToCleanCut(cf_name_, vstorage_, - &start_level_inputs_)) { - break; - } - } - if (i == vstorage_->BottommostFilesMarkedForCompaction().size()) { - start_level_inputs_.clear(); - } else { - assert(!start_level_inputs_.empty()); - compaction_reason_ = CompactionReason::kBottommostFiles; - return; - } + PickFileToCompact(vstorage_->BottommostFilesMarkedForCompaction(), false); + if (!start_level_inputs_.empty()) { + compaction_reason_ = CompactionReason::kBottommostFiles; + return; } // TTL Compaction - if (start_level_inputs_.empty()) { - PickExpiredTtlFiles(); - if (!start_level_inputs_.empty()) { - compaction_reason_ = CompactionReason::kTtl; - return; - } + PickFileToCompact(vstorage_->ExpiredTtlFiles(), true); + if (!start_level_inputs_.empty()) { + compaction_reason_ = CompactionReason::kTtl; + return; } // Periodic Compaction - if (start_level_inputs_.empty()) { - PickFilesMarkedForPeriodicCompaction(); - if (!start_level_inputs_.empty()) { - compaction_reason_ = CompactionReason::kPeriodicCompaction; - return; - } + PickFileToCompact(vstorage_->FilesMarkedForPeriodicCompaction(), false); + if (!start_level_inputs_.empty()) { + compaction_reason_ = CompactionReason::kPeriodicCompaction; + return; } }