From 3725179736e2b5372664163470e7ef3dc76529a4 Mon Sep 17 00:00:00 2001 From: Sfan5 Date: Mon, 9 Sep 2013 22:46:18 +0200 Subject: Use system-wide LevelDB instead of bundled one --- src/leveldb/db/version_set.h | 381 ------------------------------------------- 1 file changed, 381 deletions(-) delete mode 100644 src/leveldb/db/version_set.h (limited to 'src/leveldb/db/version_set.h') diff --git a/src/leveldb/db/version_set.h b/src/leveldb/db/version_set.h deleted file mode 100644 index 792899b7f..000000000 --- a/src/leveldb/db/version_set.h +++ /dev/null @@ -1,381 +0,0 @@ -// 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. -// -// The representation of a DBImpl consists of a set of Versions. The -// newest version is called "current". Older versions may be kept -// around to provide a consistent view to live iterators. -// -// Each Version keeps track of a set of Table files per level. The -// entire set of versions is maintained in a VersionSet. -// -// Version,VersionSet are thread-compatible, but require external -// synchronization on all accesses. - -#ifndef STORAGE_LEVELDB_DB_VERSION_SET_H_ -#define STORAGE_LEVELDB_DB_VERSION_SET_H_ - -#include -#include -#include -#include "db/dbformat.h" -#include "db/version_edit.h" -#include "port/port.h" -#include "port/thread_annotations.h" - -namespace leveldb { - -namespace log { class Writer; } - -class Compaction; -class Iterator; -class MemTable; -class TableBuilder; -class TableCache; -class Version; -class VersionSet; -class WritableFile; - -// Return the smallest index i such that files[i]->largest >= key. -// Return files.size() if there is no such file. -// REQUIRES: "files" contains a sorted list of non-overlapping files. -extern int FindFile(const InternalKeyComparator& icmp, - const std::vector& files, - const Slice& key); - -// Returns true iff some file in "files" overlaps the user key range -// [*smallest,*largest]. -// smallest==NULL represents a key smaller than all keys in the DB. -// largest==NULL represents a key largest than all keys in the DB. -// REQUIRES: If disjoint_sorted_files, files[] contains disjoint ranges -// in sorted order. -extern bool SomeFileOverlapsRange( - const InternalKeyComparator& icmp, - bool disjoint_sorted_files, - const std::vector& files, - const Slice* smallest_user_key, - const Slice* largest_user_key); - -class Version { - public: - // Append to *iters a sequence of iterators that will - // yield the contents of this Version when merged together. - // REQUIRES: This version has been saved (see VersionSet::SaveTo) - void AddIterators(const ReadOptions&, std::vector* iters); - - // Lookup the value for key. If found, store it in *val and - // return OK. Else return a non-OK status. Fills *stats. - // REQUIRES: lock is not held - struct GetStats { - FileMetaData* seek_file; - int seek_file_level; - }; - Status Get(const ReadOptions&, const LookupKey& key, std::string* val, - GetStats* stats); - - // Adds "stats" into the current state. Returns true if a new - // compaction may need to be triggered, false otherwise. - // REQUIRES: lock is held - bool UpdateStats(const GetStats& stats); - - // Reference count management (so Versions do not disappear out from - // under live iterators) - void Ref(); - void Unref(); - - void GetOverlappingInputs( - int level, - const InternalKey* begin, // NULL means before all keys - const InternalKey* end, // NULL means after all keys - std::vector* inputs); - - // Returns true iff some file in the specified level overlaps - // some part of [*smallest_user_key,*largest_user_key]. - // smallest_user_key==NULL represents a key smaller than all keys in the DB. - // largest_user_key==NULL represents a key largest than all keys in the DB. - bool OverlapInLevel(int level, - const Slice* smallest_user_key, - const Slice* largest_user_key); - - // Return the level at which we should place a new memtable compaction - // result that covers the range [smallest_user_key,largest_user_key]. - int PickLevelForMemTableOutput(const Slice& smallest_user_key, - const Slice& largest_user_key); - - int NumFiles(int level) const { return files_[level].size(); } - - // Return a human readable string that describes this version's contents. - std::string DebugString() const; - - private: - friend class Compaction; - friend class VersionSet; - - class LevelFileNumIterator; - Iterator* NewConcatenatingIterator(const ReadOptions&, int level) const; - - VersionSet* vset_; // VersionSet to which this Version belongs - Version* next_; // Next version in linked list - Version* prev_; // Previous version in linked list - int refs_; // Number of live refs to this version - - // List of files per level - std::vector files_[config::kNumLevels]; - - // Next file to compact based on seek stats. - FileMetaData* file_to_compact_; - int file_to_compact_level_; - - // Level that should be compacted next and its compaction score. - // Score < 1 means compaction is not strictly needed. These fields - // are initialized by Finalize(). - double compaction_score_; - int compaction_level_; - - explicit Version(VersionSet* vset) - : vset_(vset), next_(this), prev_(this), refs_(0), - file_to_compact_(NULL), - file_to_compact_level_(-1), - compaction_score_(-1), - compaction_level_(-1) { - } - - ~Version(); - - // No copying allowed - Version(const Version&); - void operator=(const Version&); -}; - -class VersionSet { - public: - VersionSet(const std::string& dbname, - const Options* options, - TableCache* table_cache, - const InternalKeyComparator*); - ~VersionSet(); - - // Apply *edit to the current version to form a new descriptor that - // is both saved to persistent state and installed as the new - // current version. Will release *mu while actually writing to the file. - // REQUIRES: *mu is held on entry. - // REQUIRES: no other thread concurrently calls LogAndApply() - Status LogAndApply(VersionEdit* edit, port::Mutex* mu) - EXCLUSIVE_LOCKS_REQUIRED(mu); - - // Recover the last saved descriptor from persistent storage. - Status Recover(); - - // Return the current version. - Version* current() const { return current_; } - - // Return the current manifest file number - uint64_t ManifestFileNumber() const { return manifest_file_number_; } - - // Allocate and return a new file number - uint64_t NewFileNumber() { return next_file_number_++; } - - // Arrange to reuse "file_number" unless a newer file number has - // already been allocated. - // REQUIRES: "file_number" was returned by a call to NewFileNumber(). - void ReuseFileNumber(uint64_t file_number) { - if (next_file_number_ == file_number + 1) { - next_file_number_ = file_number; - } - } - - // Return the number of Table files at the specified level. - int NumLevelFiles(int level) const; - - // Return the combined file size of all files at the specified level. - int64_t NumLevelBytes(int level) const; - - // Return the last sequence number. - uint64_t LastSequence() const { return last_sequence_; } - - // Set the last sequence number to s. - void SetLastSequence(uint64_t s) { - assert(s >= last_sequence_); - last_sequence_ = s; - } - - // Mark the specified file number as used. - void MarkFileNumberUsed(uint64_t number); - - // Return the current log file number. - uint64_t LogNumber() const { return log_number_; } - - // Return the log file number for the log file that is currently - // being compacted, or zero if there is no such log file. - uint64_t PrevLogNumber() const { return prev_log_number_; } - - // Pick level and inputs for a new compaction. - // Returns NULL if there is no compaction to be done. - // Otherwise returns a pointer to a heap-allocated object that - // describes the compaction. Caller should delete the result. - Compaction* PickCompaction(); - - // Return a compaction object for compacting the range [begin,end] in - // the specified level. Returns NULL if there is nothing in that - // level that overlaps the specified range. Caller should delete - // the result. - Compaction* CompactRange( - int level, - const InternalKey* begin, - const InternalKey* end); - - // Return the maximum overlapping data (in bytes) at next level for any - // file at a level >= 1. - int64_t MaxNextLevelOverlappingBytes(); - - // Create an iterator that reads over the compaction inputs for "*c". - // The caller should delete the iterator when no longer needed. - Iterator* MakeInputIterator(Compaction* c); - - // Returns true iff some level needs a compaction. - bool NeedsCompaction() const { - Version* v = current_; - return (v->compaction_score_ >= 1) || (v->file_to_compact_ != NULL); - } - - // Add all files listed in any live version to *live. - // May also mutate some internal state. - void AddLiveFiles(std::set* live); - - // Return the approximate offset in the database of the data for - // "key" as of version "v". - uint64_t ApproximateOffsetOf(Version* v, const InternalKey& key); - - // Return a human-readable short (single-line) summary of the number - // of files per level. Uses *scratch as backing store. - struct LevelSummaryStorage { - char buffer[100]; - }; - const char* LevelSummary(LevelSummaryStorage* scratch) const; - - private: - class Builder; - - friend class Compaction; - friend class Version; - - void Finalize(Version* v); - - void GetRange(const std::vector& inputs, - InternalKey* smallest, - InternalKey* largest); - - void GetRange2(const std::vector& inputs1, - const std::vector& inputs2, - InternalKey* smallest, - InternalKey* largest); - - void SetupOtherInputs(Compaction* c); - - // Save current contents to *log - Status WriteSnapshot(log::Writer* log); - - void AppendVersion(Version* v); - - Env* const env_; - const std::string dbname_; - const Options* const options_; - TableCache* const table_cache_; - const InternalKeyComparator icmp_; - uint64_t next_file_number_; - uint64_t manifest_file_number_; - uint64_t last_sequence_; - uint64_t log_number_; - uint64_t prev_log_number_; // 0 or backing store for memtable being compacted - - // Opened lazily - WritableFile* descriptor_file_; - log::Writer* descriptor_log_; - Version dummy_versions_; // Head of circular doubly-linked list of versions. - Version* current_; // == dummy_versions_.prev_ - - // Per-level key at which the next compaction at that level should start. - // Either an empty string, or a valid InternalKey. - std::string compact_pointer_[config::kNumLevels]; - - // No copying allowed - VersionSet(const VersionSet&); - void operator=(const VersionSet&); -}; - -// A Compaction encapsulates information about a compaction. -class Compaction { - public: - ~Compaction(); - - // Return the level that is being compacted. Inputs from "level" - // and "level+1" will be merged to produce a set of "level+1" files. - int level() const { return level_; } - - // Return the object that holds the edits to the descriptor done - // by this compaction. - VersionEdit* edit() { return &edit_; } - - // "which" must be either 0 or 1 - int num_input_files(int which) const { return inputs_[which].size(); } - - // Return the ith input file at "level()+which" ("which" must be 0 or 1). - FileMetaData* input(int which, int i) const { return inputs_[which][i]; } - - // Maximum size of files to build during this compaction. - uint64_t MaxOutputFileSize() const { return max_output_file_size_; } - - // Is this a trivial compaction that can be implemented by just - // moving a single input file to the next level (no merging or splitting) - bool IsTrivialMove() const; - - // Add all inputs to this compaction as delete operations to *edit. - void AddInputDeletions(VersionEdit* edit); - - // Returns true if the information we have available guarantees that - // the compaction is producing data in "level+1" for which no data exists - // in levels greater than "level+1". - bool IsBaseLevelForKey(const Slice& user_key); - - // Returns true iff we should stop building the current output - // before processing "internal_key". - bool ShouldStopBefore(const Slice& internal_key); - - // Release the input version for the compaction, once the compaction - // is successful. - void ReleaseInputs(); - - private: - friend class Version; - friend class VersionSet; - - explicit Compaction(int level); - - int level_; - uint64_t max_output_file_size_; - Version* input_version_; - VersionEdit edit_; - - // Each compaction reads inputs from "level_" and "level_+1" - std::vector inputs_[2]; // The two sets of inputs - - // State used to check for number of of overlapping grandparent files - // (parent == level_ + 1, grandparent == level_ + 2) - std::vector grandparents_; - size_t grandparent_index_; // Index in grandparent_starts_ - bool seen_key_; // Some output key has been seen - int64_t overlapped_bytes_; // Bytes of overlap between current output - // and grandparent files - - // State for implementing IsBaseLevelForKey - - // level_ptrs_ holds indices into input_version_->levels_: our state - // is that we are positioned at one of the file ranges for each - // higher level than the ones involved in this compaction (i.e. for - // all L >= level_ + 2). - size_t level_ptrs_[config::kNumLevels]; -}; - -} // namespace leveldb - -#endif // STORAGE_LEVELDB_DB_VERSION_SET_H_ -- cgit v1.2.3