fork of https://github.com/oxigraph/rocksdb and https://github.com/facebook/rocksdb for nextgraph and oxigraph
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
554 lines
22 KiB
554 lines
22 KiB
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
|
|
// This source code is licensed under the BSD-style license found in the
|
|
// LICENSE file in the root directory of this source tree. An additional grant
|
|
// of patent rights can be found in the PATENTS file in the same 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.
|
|
|
|
#pragma once
|
|
|
|
#include <unordered_map>
|
|
#include <string>
|
|
#include <vector>
|
|
#include <atomic>
|
|
|
|
#include "db/memtable_list.h"
|
|
#include "db/table_cache.h"
|
|
#include "db/table_properties_collector.h"
|
|
#include "db/write_batch_internal.h"
|
|
#include "db/write_controller.h"
|
|
#include "rocksdb/compaction_job_stats.h"
|
|
#include "rocksdb/db.h"
|
|
#include "rocksdb/env.h"
|
|
#include "rocksdb/options.h"
|
|
#include "util/cf_options.h"
|
|
#include "util/thread_local.h"
|
|
|
|
namespace rocksdb {
|
|
|
|
class Version;
|
|
class VersionSet;
|
|
class MemTable;
|
|
class MemTableListVersion;
|
|
class CompactionPicker;
|
|
class Compaction;
|
|
class InternalKey;
|
|
class InternalStats;
|
|
class ColumnFamilyData;
|
|
class DBImpl;
|
|
class LogBuffer;
|
|
class InstrumentedMutex;
|
|
class InstrumentedMutexLock;
|
|
|
|
extern const double kSlowdownRatio;
|
|
|
|
// ColumnFamilyHandleImpl is the class that clients use to access different
|
|
// column families. It has non-trivial destructor, which gets called when client
|
|
// is done using the column family
|
|
class ColumnFamilyHandleImpl : public ColumnFamilyHandle {
|
|
public:
|
|
// create while holding the mutex
|
|
ColumnFamilyHandleImpl(
|
|
ColumnFamilyData* cfd, DBImpl* db, InstrumentedMutex* mutex);
|
|
// destroy without mutex
|
|
virtual ~ColumnFamilyHandleImpl();
|
|
virtual ColumnFamilyData* cfd() const { return cfd_; }
|
|
|
|
virtual uint32_t GetID() const override;
|
|
virtual const std::string& GetName() const override;
|
|
virtual Status GetDescriptor(ColumnFamilyDescriptor* desc) override;
|
|
virtual const Comparator* GetComparator() const override;
|
|
|
|
private:
|
|
ColumnFamilyData* cfd_;
|
|
DBImpl* db_;
|
|
InstrumentedMutex* mutex_;
|
|
};
|
|
|
|
// Does not ref-count ColumnFamilyData
|
|
// We use this dummy ColumnFamilyHandleImpl because sometimes MemTableInserter
|
|
// calls DBImpl methods. When this happens, MemTableInserter need access to
|
|
// ColumnFamilyHandle (same as the client would need). In that case, we feed
|
|
// MemTableInserter dummy ColumnFamilyHandle and enable it to call DBImpl
|
|
// methods
|
|
class ColumnFamilyHandleInternal : public ColumnFamilyHandleImpl {
|
|
public:
|
|
ColumnFamilyHandleInternal()
|
|
: ColumnFamilyHandleImpl(nullptr, nullptr, nullptr) {}
|
|
|
|
void SetCFD(ColumnFamilyData* _cfd) { internal_cfd_ = _cfd; }
|
|
virtual ColumnFamilyData* cfd() const override { return internal_cfd_; }
|
|
|
|
private:
|
|
ColumnFamilyData* internal_cfd_;
|
|
};
|
|
|
|
// holds references to memtable, all immutable memtables and version
|
|
struct SuperVersion {
|
|
// Accessing members of this class is not thread-safe and requires external
|
|
// synchronization (ie db mutex held or on write thread).
|
|
MemTable* mem;
|
|
MemTableListVersion* imm;
|
|
Version* current;
|
|
MutableCFOptions mutable_cf_options;
|
|
// Version number of the current SuperVersion
|
|
uint64_t version_number;
|
|
|
|
InstrumentedMutex* db_mutex;
|
|
|
|
// should be called outside the mutex
|
|
SuperVersion() = default;
|
|
~SuperVersion();
|
|
SuperVersion* Ref();
|
|
// If Unref() returns true, Cleanup() should be called with mutex held
|
|
// before deleting this SuperVersion.
|
|
bool Unref();
|
|
|
|
// call these two methods with db mutex held
|
|
// Cleanup unrefs mem, imm and current. Also, it stores all memtables
|
|
// that needs to be deleted in to_delete vector. Unrefing those
|
|
// objects needs to be done in the mutex
|
|
void Cleanup();
|
|
void Init(MemTable* new_mem, MemTableListVersion* new_imm,
|
|
Version* new_current);
|
|
|
|
// The value of dummy is not actually used. kSVInUse takes its address as a
|
|
// mark in the thread local storage to indicate the SuperVersion is in use
|
|
// by thread. This way, the value of kSVInUse is guaranteed to have no
|
|
// conflict with SuperVersion object address and portable on different
|
|
// platform.
|
|
static int dummy;
|
|
static void* const kSVInUse;
|
|
static void* const kSVObsolete;
|
|
|
|
private:
|
|
std::atomic<uint32_t> refs;
|
|
// We need to_delete because during Cleanup(), imm->Unref() returns
|
|
// all memtables that we need to free through this vector. We then
|
|
// delete all those memtables outside of mutex, during destruction
|
|
autovector<MemTable*> to_delete;
|
|
};
|
|
|
|
extern Status CheckCompressionSupported(const ColumnFamilyOptions& cf_options);
|
|
|
|
extern Status CheckConcurrentWritesSupported(
|
|
const ColumnFamilyOptions& cf_options);
|
|
|
|
extern ColumnFamilyOptions SanitizeOptions(const DBOptions& db_options,
|
|
const InternalKeyComparator* icmp,
|
|
const ColumnFamilyOptions& src);
|
|
// Wrap user defined table proproties collector factories `from cf_options`
|
|
// into internal ones in int_tbl_prop_collector_factories. Add a system internal
|
|
// one too.
|
|
extern void GetIntTblPropCollectorFactory(
|
|
const ColumnFamilyOptions& cf_options,
|
|
std::vector<std::unique_ptr<IntTblPropCollectorFactory>>*
|
|
int_tbl_prop_collector_factories);
|
|
|
|
class ColumnFamilySet;
|
|
|
|
// This class keeps all the data that a column family needs.
|
|
// Most methods require DB mutex held, unless otherwise noted
|
|
class ColumnFamilyData {
|
|
public:
|
|
~ColumnFamilyData();
|
|
|
|
// thread-safe
|
|
uint32_t GetID() const { return id_; }
|
|
// thread-safe
|
|
const std::string& GetName() const { return name_; }
|
|
|
|
// Ref() can only be called from a context where the caller can guarantee
|
|
// that ColumnFamilyData is alive (while holding a non-zero ref already,
|
|
// holding a DB mutex, or as the leader in a write batch group).
|
|
void Ref() { refs_.fetch_add(1, std::memory_order_relaxed); }
|
|
|
|
// Unref decreases the reference count, but does not handle deletion
|
|
// when the count goes to 0. If this method returns true then the
|
|
// caller should delete the instance immediately, or later, by calling
|
|
// FreeDeadColumnFamilies(). Unref() can only be called while holding
|
|
// a DB mutex, or during single-threaded recovery.
|
|
bool Unref() {
|
|
int old_refs = refs_.fetch_sub(1, std::memory_order_relaxed);
|
|
assert(old_refs > 0);
|
|
return old_refs == 1;
|
|
}
|
|
|
|
// SetDropped() can only be called under following conditions:
|
|
// 1) Holding a DB mutex,
|
|
// 2) from single-threaded write thread, AND
|
|
// 3) from single-threaded VersionSet::LogAndApply()
|
|
// After dropping column family no other operation on that column family
|
|
// will be executed. All the files and memory will be, however, kept around
|
|
// until client drops the column family handle. That way, client can still
|
|
// access data from dropped column family.
|
|
// Column family can be dropped and still alive. In that state:
|
|
// *) Compaction and flush is not executed on the dropped column family.
|
|
// *) Client can continue reading from column family. Writes will fail unless
|
|
// WriteOptions::ignore_missing_column_families is true
|
|
// When the dropped column family is unreferenced, then we:
|
|
// *) Remove column family from the linked list maintained by ColumnFamilySet
|
|
// *) delete all memory associated with that column family
|
|
// *) delete all the files associated with that column family
|
|
void SetDropped();
|
|
bool IsDropped() const { return dropped_; }
|
|
|
|
// thread-safe
|
|
int NumberLevels() const { return ioptions_.num_levels; }
|
|
|
|
void SetLogNumber(uint64_t log_number) { log_number_ = log_number; }
|
|
uint64_t GetLogNumber() const { return log_number_; }
|
|
|
|
// thread-safe
|
|
const EnvOptions* soptions() const;
|
|
const ImmutableCFOptions* ioptions() const { return &ioptions_; }
|
|
// REQUIRES: DB mutex held
|
|
// This returns the MutableCFOptions used by current SuperVersion
|
|
// You should use this API to reference MutableCFOptions most of the time.
|
|
const MutableCFOptions* GetCurrentMutableCFOptions() const {
|
|
return &(super_version_->mutable_cf_options);
|
|
}
|
|
// REQUIRES: DB mutex held
|
|
// This returns the latest MutableCFOptions, which may be not in effect yet.
|
|
const MutableCFOptions* GetLatestMutableCFOptions() const {
|
|
return &mutable_cf_options_;
|
|
}
|
|
|
|
// REQUIRES: DB mutex held
|
|
// Build ColumnFamiliesOptions with immutable options and latest mutable
|
|
// options.
|
|
ColumnFamilyOptions GetLatestCFOptions() const;
|
|
|
|
#ifndef ROCKSDB_LITE
|
|
// REQUIRES: DB mutex held
|
|
Status SetOptions(
|
|
const std::unordered_map<std::string, std::string>& options_map);
|
|
#endif // ROCKSDB_LITE
|
|
|
|
InternalStats* internal_stats() { return internal_stats_.get(); }
|
|
|
|
MemTableList* imm() { return &imm_; }
|
|
MemTable* mem() { return mem_; }
|
|
Version* current() { return current_; }
|
|
Version* dummy_versions() { return dummy_versions_; }
|
|
void SetCurrent(Version* _current);
|
|
uint64_t GetNumLiveVersions() const; // REQUIRE: DB mutex held
|
|
uint64_t GetTotalSstFilesSize() const; // REQUIRE: DB mutex held
|
|
void SetMemtable(MemTable* new_mem) { mem_ = new_mem; }
|
|
|
|
// See Memtable constructor for explanation of earliest_seq param.
|
|
MemTable* ConstructNewMemtable(const MutableCFOptions& mutable_cf_options,
|
|
SequenceNumber earliest_seq);
|
|
void CreateNewMemtable(const MutableCFOptions& mutable_cf_options,
|
|
SequenceNumber earliest_seq);
|
|
|
|
TableCache* table_cache() const { return table_cache_.get(); }
|
|
|
|
// See documentation in compaction_picker.h
|
|
// REQUIRES: DB mutex held
|
|
bool NeedsCompaction() const;
|
|
// REQUIRES: DB mutex held
|
|
Compaction* PickCompaction(const MutableCFOptions& mutable_options,
|
|
LogBuffer* log_buffer);
|
|
// A flag to tell a manual compaction is to compact all levels together
|
|
// instad of for specific level.
|
|
static const int kCompactAllLevels;
|
|
// A flag to tell a manual compaction's output is base level.
|
|
static const int kCompactToBaseLevel;
|
|
// REQUIRES: DB mutex held
|
|
Compaction* CompactRange(const MutableCFOptions& mutable_cf_options,
|
|
int input_level, int output_level,
|
|
uint32_t output_path_id, const InternalKey* begin,
|
|
const InternalKey* end, InternalKey** compaction_end,
|
|
bool* manual_conflict);
|
|
|
|
CompactionPicker* compaction_picker() { return compaction_picker_.get(); }
|
|
// thread-safe
|
|
const Comparator* user_comparator() const {
|
|
return internal_comparator_.user_comparator();
|
|
}
|
|
// thread-safe
|
|
const InternalKeyComparator& internal_comparator() const {
|
|
return internal_comparator_;
|
|
}
|
|
|
|
const std::vector<std::unique_ptr<IntTblPropCollectorFactory>>*
|
|
int_tbl_prop_collector_factories() const {
|
|
return &int_tbl_prop_collector_factories_;
|
|
}
|
|
|
|
SuperVersion* GetSuperVersion() { return super_version_; }
|
|
// thread-safe
|
|
// Return a already referenced SuperVersion to be used safely.
|
|
SuperVersion* GetReferencedSuperVersion(InstrumentedMutex* db_mutex);
|
|
// thread-safe
|
|
// Get SuperVersion stored in thread local storage. If it does not exist,
|
|
// get a reference from a current SuperVersion.
|
|
SuperVersion* GetThreadLocalSuperVersion(InstrumentedMutex* db_mutex);
|
|
// Try to return SuperVersion back to thread local storage. Retrun true on
|
|
// success and false on failure. It fails when the thread local storage
|
|
// contains anything other than SuperVersion::kSVInUse flag.
|
|
bool ReturnThreadLocalSuperVersion(SuperVersion* sv);
|
|
// thread-safe
|
|
uint64_t GetSuperVersionNumber() const {
|
|
return super_version_number_.load();
|
|
}
|
|
// will return a pointer to SuperVersion* if previous SuperVersion
|
|
// if its reference count is zero and needs deletion or nullptr if not
|
|
// As argument takes a pointer to allocated SuperVersion to enable
|
|
// the clients to allocate SuperVersion outside of mutex.
|
|
// IMPORTANT: Only call this from DBImpl::InstallSuperVersion()
|
|
SuperVersion* InstallSuperVersion(SuperVersion* new_superversion,
|
|
InstrumentedMutex* db_mutex,
|
|
const MutableCFOptions& mutable_cf_options);
|
|
SuperVersion* InstallSuperVersion(SuperVersion* new_superversion,
|
|
InstrumentedMutex* db_mutex);
|
|
|
|
void ResetThreadLocalSuperVersions();
|
|
|
|
// Protected by DB mutex
|
|
void set_pending_flush(bool value) { pending_flush_ = value; }
|
|
void set_pending_compaction(bool value) { pending_compaction_ = value; }
|
|
bool pending_flush() { return pending_flush_; }
|
|
bool pending_compaction() { return pending_compaction_; }
|
|
|
|
// Recalculate some small conditions, which are changed only during
|
|
// compaction, adding new memtable and/or
|
|
// recalculation of compaction score. These values are used in
|
|
// DBImpl::MakeRoomForWrite function to decide, if it need to make
|
|
// a write stall
|
|
void RecalculateWriteStallConditions(
|
|
const MutableCFOptions& mutable_cf_options);
|
|
|
|
private:
|
|
friend class ColumnFamilySet;
|
|
ColumnFamilyData(uint32_t id, const std::string& name,
|
|
Version* dummy_versions, Cache* table_cache,
|
|
WriteBufferManager* write_buffer_manager,
|
|
const ColumnFamilyOptions& options,
|
|
const DBOptions* db_options, const EnvOptions& env_options,
|
|
ColumnFamilySet* column_family_set);
|
|
|
|
uint32_t id_;
|
|
const std::string name_;
|
|
Version* dummy_versions_; // Head of circular doubly-linked list of versions.
|
|
Version* current_; // == dummy_versions->prev_
|
|
|
|
std::atomic<int> refs_; // outstanding references to ColumnFamilyData
|
|
bool dropped_; // true if client dropped it
|
|
|
|
const InternalKeyComparator internal_comparator_;
|
|
std::vector<std::unique_ptr<IntTblPropCollectorFactory>>
|
|
int_tbl_prop_collector_factories_;
|
|
|
|
const Options options_;
|
|
const ImmutableCFOptions ioptions_;
|
|
MutableCFOptions mutable_cf_options_;
|
|
|
|
std::unique_ptr<TableCache> table_cache_;
|
|
|
|
std::unique_ptr<InternalStats> internal_stats_;
|
|
|
|
WriteBufferManager* write_buffer_manager_;
|
|
|
|
MemTable* mem_;
|
|
MemTableList imm_;
|
|
SuperVersion* super_version_;
|
|
|
|
// An ordinal representing the current SuperVersion. Updated by
|
|
// InstallSuperVersion(), i.e. incremented every time super_version_
|
|
// changes.
|
|
std::atomic<uint64_t> super_version_number_;
|
|
|
|
// Thread's local copy of SuperVersion pointer
|
|
// This needs to be destructed before mutex_
|
|
std::unique_ptr<ThreadLocalPtr> local_sv_;
|
|
|
|
// pointers for a circular linked list. we use it to support iterations over
|
|
// all column families that are alive (note: dropped column families can also
|
|
// be alive as long as client holds a reference)
|
|
ColumnFamilyData* next_;
|
|
ColumnFamilyData* prev_;
|
|
|
|
// This is the earliest log file number that contains data from this
|
|
// Column Family. All earlier log files must be ignored and not
|
|
// recovered from
|
|
uint64_t log_number_;
|
|
|
|
// An object that keeps all the compaction stats
|
|
// and picks the next compaction
|
|
std::unique_ptr<CompactionPicker> compaction_picker_;
|
|
|
|
ColumnFamilySet* column_family_set_;
|
|
|
|
std::unique_ptr<WriteControllerToken> write_controller_token_;
|
|
|
|
// If true --> this ColumnFamily is currently present in DBImpl::flush_queue_
|
|
bool pending_flush_;
|
|
|
|
// If true --> this ColumnFamily is currently present in
|
|
// DBImpl::compaction_queue_
|
|
bool pending_compaction_;
|
|
|
|
uint64_t prev_compaction_needed_bytes_;
|
|
};
|
|
|
|
// ColumnFamilySet has interesting thread-safety requirements
|
|
// * CreateColumnFamily() or RemoveColumnFamily() -- need to be protected by DB
|
|
// mutex AND executed in the write thread.
|
|
// CreateColumnFamily() should ONLY be called from VersionSet::LogAndApply() AND
|
|
// single-threaded write thread. It is also called during Recovery and in
|
|
// DumpManifest().
|
|
// RemoveColumnFamily() is only called from SetDropped(). DB mutex needs to be
|
|
// held and it needs to be executed from the write thread. SetDropped() also
|
|
// guarantees that it will be called only from single-threaded LogAndApply(),
|
|
// but this condition is not that important.
|
|
// * Iteration -- hold DB mutex, but you can release it in the body of
|
|
// iteration. If you release DB mutex in body, reference the column
|
|
// family before the mutex and unreference after you unlock, since the column
|
|
// family might get dropped when the DB mutex is released
|
|
// * GetDefault() -- thread safe
|
|
// * GetColumnFamily() -- either inside of DB mutex or from a write thread
|
|
// * GetNextColumnFamilyID(), GetMaxColumnFamily(), UpdateMaxColumnFamily(),
|
|
// NumberOfColumnFamilies -- inside of DB mutex
|
|
class ColumnFamilySet {
|
|
public:
|
|
// ColumnFamilySet supports iteration
|
|
class iterator {
|
|
public:
|
|
explicit iterator(ColumnFamilyData* cfd)
|
|
: current_(cfd) {}
|
|
iterator& operator++() {
|
|
// dropped column families might still be included in this iteration
|
|
// (we're only removing them when client drops the last reference to the
|
|
// column family).
|
|
// dummy is never dead, so this will never be infinite
|
|
do {
|
|
current_ = current_->next_;
|
|
} while (current_->refs_.load(std::memory_order_relaxed) == 0);
|
|
return *this;
|
|
}
|
|
bool operator!=(const iterator& other) {
|
|
return this->current_ != other.current_;
|
|
}
|
|
ColumnFamilyData* operator*() { return current_; }
|
|
|
|
private:
|
|
ColumnFamilyData* current_;
|
|
};
|
|
|
|
ColumnFamilySet(const std::string& dbname, const DBOptions* db_options,
|
|
const EnvOptions& env_options, Cache* table_cache,
|
|
WriteBufferManager* write_buffer_manager,
|
|
WriteController* write_controller);
|
|
~ColumnFamilySet();
|
|
|
|
ColumnFamilyData* GetDefault() const;
|
|
// GetColumnFamily() calls return nullptr if column family is not found
|
|
ColumnFamilyData* GetColumnFamily(uint32_t id) const;
|
|
ColumnFamilyData* GetColumnFamily(const std::string& name) const;
|
|
// this call will return the next available column family ID. it guarantees
|
|
// that there is no column family with id greater than or equal to the
|
|
// returned value in the current running instance or anytime in RocksDB
|
|
// instance history.
|
|
uint32_t GetNextColumnFamilyID();
|
|
uint32_t GetMaxColumnFamily();
|
|
void UpdateMaxColumnFamily(uint32_t new_max_column_family);
|
|
size_t NumberOfColumnFamilies() const;
|
|
|
|
ColumnFamilyData* CreateColumnFamily(const std::string& name, uint32_t id,
|
|
Version* dummy_version,
|
|
const ColumnFamilyOptions& options);
|
|
|
|
iterator begin() { return iterator(dummy_cfd_->next_); }
|
|
iterator end() { return iterator(dummy_cfd_); }
|
|
|
|
// REQUIRES: DB mutex held
|
|
// Don't call while iterating over ColumnFamilySet
|
|
void FreeDeadColumnFamilies();
|
|
|
|
Cache* get_table_cache() { return table_cache_; }
|
|
|
|
private:
|
|
friend class ColumnFamilyData;
|
|
// helper function that gets called from cfd destructor
|
|
// REQUIRES: DB mutex held
|
|
void RemoveColumnFamily(ColumnFamilyData* cfd);
|
|
|
|
// column_families_ and column_family_data_ need to be protected:
|
|
// * when mutating both conditions have to be satisfied:
|
|
// 1. DB mutex locked
|
|
// 2. thread currently in single-threaded write thread
|
|
// * when reading, at least one condition needs to be satisfied:
|
|
// 1. DB mutex locked
|
|
// 2. accessed from a single-threaded write thread
|
|
std::unordered_map<std::string, uint32_t> column_families_;
|
|
std::unordered_map<uint32_t, ColumnFamilyData*> column_family_data_;
|
|
|
|
uint32_t max_column_family_;
|
|
ColumnFamilyData* dummy_cfd_;
|
|
// We don't hold the refcount here, since default column family always exists
|
|
// We are also not responsible for cleaning up default_cfd_cache_. This is
|
|
// just a cache that makes common case (accessing default column family)
|
|
// faster
|
|
ColumnFamilyData* default_cfd_cache_;
|
|
|
|
const std::string db_name_;
|
|
const DBOptions* const db_options_;
|
|
const EnvOptions env_options_;
|
|
Cache* table_cache_;
|
|
WriteBufferManager* write_buffer_manager_;
|
|
WriteController* write_controller_;
|
|
};
|
|
|
|
// We use ColumnFamilyMemTablesImpl to provide WriteBatch a way to access
|
|
// memtables of different column families (specified by ID in the write batch)
|
|
class ColumnFamilyMemTablesImpl : public ColumnFamilyMemTables {
|
|
public:
|
|
explicit ColumnFamilyMemTablesImpl(ColumnFamilySet* column_family_set)
|
|
: column_family_set_(column_family_set), current_(nullptr) {}
|
|
|
|
// Constructs a ColumnFamilyMemTablesImpl equivalent to one constructed
|
|
// with the arguments used to construct *orig.
|
|
explicit ColumnFamilyMemTablesImpl(ColumnFamilyMemTablesImpl* orig)
|
|
: column_family_set_(orig->column_family_set_), current_(nullptr) {}
|
|
|
|
// sets current_ to ColumnFamilyData with column_family_id
|
|
// returns false if column family doesn't exist
|
|
// REQUIRES: use this function of DBImpl::column_family_memtables_ should be
|
|
// under a DB mutex OR from a write thread
|
|
bool Seek(uint32_t column_family_id) override;
|
|
|
|
// Returns log number of the selected column family
|
|
// REQUIRES: under a DB mutex OR from a write thread
|
|
uint64_t GetLogNumber() const override;
|
|
|
|
// REQUIRES: Seek() called first
|
|
// REQUIRES: use this function of DBImpl::column_family_memtables_ should be
|
|
// under a DB mutex OR from a write thread
|
|
virtual MemTable* GetMemTable() const override;
|
|
|
|
// Returns column family handle for the selected column family
|
|
// REQUIRES: use this function of DBImpl::column_family_memtables_ should be
|
|
// under a DB mutex OR from a write thread
|
|
virtual ColumnFamilyHandle* GetColumnFamilyHandle() override;
|
|
|
|
// Cannot be called while another thread is calling Seek().
|
|
// REQUIRES: use this function of DBImpl::column_family_memtables_ should be
|
|
// under a DB mutex OR from a write thread
|
|
virtual ColumnFamilyData* current() override { return current_; }
|
|
|
|
private:
|
|
ColumnFamilySet* column_family_set_;
|
|
ColumnFamilyData* current_;
|
|
ColumnFamilyHandleInternal handle_;
|
|
};
|
|
|
|
extern uint32_t GetColumnFamilyID(ColumnFamilyHandle* column_family);
|
|
|
|
extern const Comparator* GetColumnFamilyUserComparator(
|
|
ColumnFamilyHandle* column_family);
|
|
|
|
} // namespace rocksdb
|
|
|