rocksdb/utilities/transactions/write_prepared_txn.cc
Maysam Yabandeh eb6425303e Update WritePrepared with the pseudo code
Summary:
Implement the main body of WritePrepared pseudo code. This includes PrepareInternal and CommitInternal, as well as AddCommitted which updates the commit map. It also provides a IsInSnapshot method that could be later called form the read path to decide if a version is in the read snapshot or it should other be skipped.

This patch lacks unit tests and does not attempt to offer an efficient implementation. The idea is that to have the API specified so that we can work on related tasks in parallel.
Closes https://github.com/facebook/rocksdb/pull/2713

Differential Revision: D5640021

Pulled By: maysamyabandeh

fbshipit-source-id: bfa7a05e8d8498811fab714ce4b9c21530514e1c
2017-08-16 16:57:47 -07:00

89 lines
2.9 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).
#ifndef ROCKSDB_LITE
#include "utilities/transactions/write_prepared_txn.h"
#include <map>
#include "db/column_family.h"
#include "db/db_impl.h"
#include "rocksdb/db.h"
#include "rocksdb/status.h"
#include "rocksdb/utilities/transaction_db.h"
#include "utilities/transactions/pessimistic_transaction.h"
#include "utilities/transactions/pessimistic_transaction_db.h"
namespace rocksdb {
struct WriteOptions;
WritePreparedTxn::WritePreparedTxn(WritePreparedTxnDB* txn_db,
const WriteOptions& write_options,
const TransactionOptions& txn_options)
: PessimisticTransaction(txn_db, write_options, txn_options),
wpt_db_(txn_db) {
PessimisticTransaction::Initialize(txn_options);
}
Status WritePreparedTxn::CommitBatch(WriteBatch* /* unused */) {
// TODO(myabandeh) Implement this
throw std::runtime_error("CommitBatch not Implemented");
return Status::OK();
}
Status WritePreparedTxn::PrepareInternal() {
WriteOptions write_options = write_options_;
write_options.disableWAL = false;
WriteBatchInternal::MarkEndPrepare(GetWriteBatch()->GetWriteBatch(), name_);
const bool disable_memtable = true;
uint64_t seq_used;
Status s =
db_impl_->WriteImpl(write_options, GetWriteBatch()->GetWriteBatch(),
/*callback*/ nullptr, &log_number_, /*log ref*/ 0,
!disable_memtable, &seq_used);
prepare_seq_ = seq_used;
wpt_db_->AddPrepared(prepare_seq_);
return s;
}
Status WritePreparedTxn::CommitWithoutPrepareInternal() {
// TODO(myabandeh) Implement this
throw std::runtime_error("Commit not Implemented");
return Status::OK();
}
Status WritePreparedTxn::CommitInternal() {
// We take the commit-time batch and append the Commit marker.
// The Memtable will ignore the Commit marker in non-recovery mode
WriteBatch* working_batch = GetCommitTimeWriteBatch();
// TODO(myabandeh): prevent the users from writing to txn after the prepare
// phase
assert(working_batch->Count() == 0);
WriteBatchInternal::MarkCommit(working_batch, name_);
// any operations appended to this working_batch will be ignored from WAL
working_batch->MarkWalTerminationPoint();
const bool disable_memtable = true;
uint64_t seq_used;
auto s = db_impl_->WriteImpl(write_options_, working_batch, nullptr, nullptr,
log_number_, disable_memtable, &seq_used);
uint64_t& commit_seq = seq_used;
wpt_db_->AddCommitted(prepare_seq_, commit_seq);
return s;
}
Status WritePreparedTxn::Rollback() {
// TODO(myabandeh) Implement this
throw std::runtime_error("Rollback not Implemented");
return Status::OK();
}
} // namespace rocksdb
#endif // ROCKSDB_LITE