rocksdb/utilities/transactions/optimistic_transaction.h
Maysam Yabandeh bdc056f8aa Refactor PessimisticTransaction
Summary:
This patch splits Commit and Prepare into lock-related logic and db-write-related logic. It moves lock-related logic to PessimisticTransaction to be reused by all children classes and movies the existing impl of db-write-related to PrepareInternal, CommitSingleInternal, and CommitInternal in WriteCommittedTxnImpl.
Closes https://github.com/facebook/rocksdb/pull/2691

Differential Revision: D5569464

Pulled By: maysamyabandeh

fbshipit-source-id: d1b8698e69801a4126c7bc211745d05c636f5325
2017-08-07 16:12:29 -07:00

99 lines
2.8 KiB
C++

// 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).
#pragma once
#ifndef ROCKSDB_LITE
#include <stack>
#include <string>
#include <unordered_map>
#include <vector>
#include "db/write_callback.h"
#include "rocksdb/db.h"
#include "rocksdb/slice.h"
#include "rocksdb/snapshot.h"
#include "rocksdb/status.h"
#include "rocksdb/types.h"
#include "rocksdb/utilities/transaction.h"
#include "rocksdb/utilities/optimistic_transaction_db.h"
#include "rocksdb/utilities/write_batch_with_index.h"
#include "utilities/transactions/transaction_base.h"
#include "utilities/transactions/transaction_util.h"
namespace rocksdb {
class OptimisticTransaction : public TransactionBaseImpl {
public:
OptimisticTransaction(OptimisticTransactionDB* db,
const WriteOptions& write_options,
const OptimisticTransactionOptions& txn_options);
virtual ~OptimisticTransaction();
void Reinitialize(OptimisticTransactionDB* txn_db,
const WriteOptions& write_options,
const OptimisticTransactionOptions& txn_options);
Status Prepare() override;
Status Commit() override;
Status Rollback() override;
Status SetName(const TransactionName& name) override;
protected:
Status TryLock(ColumnFamilyHandle* column_family, const Slice& key,
bool read_only, bool exclusive,
bool untracked = false) override;
private:
OptimisticTransactionDB* const txn_db_;
friend class OptimisticTransactionCallback;
void Initialize(const OptimisticTransactionOptions& txn_options);
// Returns OK if it is safe to commit this transaction. Returns Status::Busy
// if there are read or write conflicts that would prevent us from committing
// OR if we can not determine whether there would be any such conflicts.
//
// Should only be called on writer thread.
Status CheckTransactionForConflicts(DB* db);
void Clear() override;
void UnlockGetForUpdate(ColumnFamilyHandle* /* unused */,
const Slice& /* unused */) override {
// Nothing to unlock.
}
// No copying allowed
OptimisticTransaction(const OptimisticTransaction&);
void operator=(const OptimisticTransaction&);
};
// Used at commit time to trigger transaction validation
class OptimisticTransactionCallback : public WriteCallback {
public:
explicit OptimisticTransactionCallback(OptimisticTransaction* txn)
: txn_(txn) {}
Status Callback(DB* db) override {
return txn_->CheckTransactionForConflicts(db);
}
bool AllowWriteBatching() override { return false; }
private:
OptimisticTransaction* txn_;
};
} // namespace rocksdb
#endif // ROCKSDB_LITE