rocksdb/utilities/transactions/pessimistic_transaction_db.cc
Thomas Fersch a42757607d Use pre-increment instead of post-increment for iterators (#5296)
Summary:
Google C++ style guide indicates pre-increment should be used for iterators: https://google.github.io/styleguide/cppguide.html#Preincrement_and_Predecrement. Replaced all instances of ' it++' by ' ++it' (where type is iterator). So this covers the cases where iterators are named 'it'.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5296

Differential Revision: D15301256

Pulled By: tfersch

fbshipit-source-id: 2803483c1392504ad3b281d21db615429c71114b
2019-05-15 13:19:15 -07:00

636 lines
21 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
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include "utilities/transactions/pessimistic_transaction_db.h"
#include <inttypes.h>
#include <string>
#include <unordered_set>
#include <vector>
#include "db/db_impl.h"
#include "rocksdb/db.h"
#include "rocksdb/options.h"
#include "rocksdb/utilities/transaction_db.h"
#include "util/cast_util.h"
#include "util/mutexlock.h"
#include "util/sync_point.h"
#include "utilities/transactions/pessimistic_transaction.h"
#include "utilities/transactions/transaction_db_mutex_impl.h"
#include "utilities/transactions/write_prepared_txn_db.h"
#include "utilities/transactions/write_unprepared_txn_db.h"
namespace rocksdb {
PessimisticTransactionDB::PessimisticTransactionDB(
DB* db, const TransactionDBOptions& txn_db_options)
: TransactionDB(db),
db_impl_(static_cast_with_check<DBImpl, DB>(db)),
txn_db_options_(txn_db_options),
lock_mgr_(this, txn_db_options_.num_stripes, txn_db_options.max_num_locks,
txn_db_options_.max_num_deadlocks,
txn_db_options_.custom_mutex_factory
? txn_db_options_.custom_mutex_factory
: std::shared_ptr<TransactionDBMutexFactory>(
new TransactionDBMutexFactoryImpl())) {
assert(db_impl_ != nullptr);
info_log_ = db_impl_->GetDBOptions().info_log;
}
// Support initiliazing PessimisticTransactionDB from a stackable db
//
// PessimisticTransactionDB
// ^ ^
// | |
// | +
// | StackableDB
// | ^
// | |
// + +
// DBImpl
// ^
// |(inherit)
// +
// DB
//
PessimisticTransactionDB::PessimisticTransactionDB(
StackableDB* db, const TransactionDBOptions& txn_db_options)
: TransactionDB(db),
db_impl_(static_cast_with_check<DBImpl, DB>(db->GetRootDB())),
txn_db_options_(txn_db_options),
lock_mgr_(this, txn_db_options_.num_stripes, txn_db_options.max_num_locks,
txn_db_options_.max_num_deadlocks,
txn_db_options_.custom_mutex_factory
? txn_db_options_.custom_mutex_factory
: std::shared_ptr<TransactionDBMutexFactory>(
new TransactionDBMutexFactoryImpl())) {
assert(db_impl_ != nullptr);
}
PessimisticTransactionDB::~PessimisticTransactionDB() {
while (!transactions_.empty()) {
delete transactions_.begin()->second;
// TODO(myabandeh): this seems to be an unsafe approach as it is not quite
// clear whether delete would also remove the entry from transactions_.
}
}
Status PessimisticTransactionDB::VerifyCFOptions(const ColumnFamilyOptions&) {
return Status::OK();
}
Status PessimisticTransactionDB::Initialize(
const std::vector<size_t>& compaction_enabled_cf_indices,
const std::vector<ColumnFamilyHandle*>& handles) {
for (auto cf_ptr : handles) {
AddColumnFamily(cf_ptr);
}
// Verify cf options
for (auto handle : handles) {
ColumnFamilyDescriptor cfd;
Status s = handle->GetDescriptor(&cfd);
if (!s.ok()) {
return s;
}
s = VerifyCFOptions(cfd.options);
if (!s.ok()) {
return s;
}
}
// Re-enable compaction for the column families that initially had
// compaction enabled.
std::vector<ColumnFamilyHandle*> compaction_enabled_cf_handles;
compaction_enabled_cf_handles.reserve(compaction_enabled_cf_indices.size());
for (auto index : compaction_enabled_cf_indices) {
compaction_enabled_cf_handles.push_back(handles[index]);
}
Status s = EnableAutoCompaction(compaction_enabled_cf_handles);
// create 'real' transactions from recovered shell transactions
auto dbimpl = reinterpret_cast<DBImpl*>(GetRootDB());
assert(dbimpl != nullptr);
auto rtrxs = dbimpl->recovered_transactions();
for (auto it = rtrxs.begin(); it != rtrxs.end(); ++it) {
auto recovered_trx = it->second;
assert(recovered_trx);
assert(recovered_trx->batches_.size() == 1);
const auto& seq = recovered_trx->batches_.begin()->first;
const auto& batch_info = recovered_trx->batches_.begin()->second;
assert(batch_info.log_number_);
assert(recovered_trx->name_.length());
WriteOptions w_options;
w_options.sync = true;
TransactionOptions t_options;
// This would help avoiding deadlock for keys that although exist in the WAL
// did not go through concurrency control. This includes the merge that
// MyRocks uses for auto-inc columns. It is safe to do so, since (i) if
// there is a conflict between the keys of two transactions that must be
// avoided, it is already avoided by the application, MyRocks, before the
// restart (ii) application, MyRocks, guarntees to rollback/commit the
// recovered transactions before new transactions start.
t_options.skip_concurrency_control = true;
Transaction* real_trx = BeginTransaction(w_options, t_options, nullptr);
assert(real_trx);
real_trx->SetLogNumber(batch_info.log_number_);
assert(seq != kMaxSequenceNumber);
if (GetTxnDBOptions().write_policy != WRITE_COMMITTED) {
real_trx->SetId(seq);
}
s = real_trx->SetName(recovered_trx->name_);
if (!s.ok()) {
break;
}
s = real_trx->RebuildFromWriteBatch(batch_info.batch_);
// WriteCommitted set this to to disable this check that is specific to
// WritePrepared txns
assert(batch_info.batch_cnt_ == 0 ||
real_trx->GetWriteBatch()->SubBatchCnt() == batch_info.batch_cnt_);
real_trx->SetState(Transaction::PREPARED);
if (!s.ok()) {
break;
}
}
if (s.ok()) {
dbimpl->DeleteAllRecoveredTransactions();
}
return s;
}
Transaction* WriteCommittedTxnDB::BeginTransaction(
const WriteOptions& write_options, const TransactionOptions& txn_options,
Transaction* old_txn) {
if (old_txn != nullptr) {
ReinitializeTransaction(old_txn, write_options, txn_options);
return old_txn;
} else {
return new WriteCommittedTxn(this, write_options, txn_options);
}
}
TransactionDBOptions PessimisticTransactionDB::ValidateTxnDBOptions(
const TransactionDBOptions& txn_db_options) {
TransactionDBOptions validated = txn_db_options;
if (txn_db_options.num_stripes == 0) {
validated.num_stripes = 1;
}
return validated;
}
Status TransactionDB::Open(const Options& options,
const TransactionDBOptions& txn_db_options,
const std::string& dbname, TransactionDB** dbptr) {
DBOptions db_options(options);
ColumnFamilyOptions cf_options(options);
std::vector<ColumnFamilyDescriptor> column_families;
column_families.push_back(
ColumnFamilyDescriptor(kDefaultColumnFamilyName, cf_options));
std::vector<ColumnFamilyHandle*> handles;
Status s = TransactionDB::Open(db_options, txn_db_options, dbname,
column_families, &handles, dbptr);
if (s.ok()) {
assert(handles.size() == 1);
// i can delete the handle since DBImpl is always holding a reference to
// default column family
delete handles[0];
}
return s;
}
Status TransactionDB::Open(
const DBOptions& db_options, const TransactionDBOptions& txn_db_options,
const std::string& dbname,
const std::vector<ColumnFamilyDescriptor>& column_families,
std::vector<ColumnFamilyHandle*>* handles, TransactionDB** dbptr) {
Status s;
DB* db = nullptr;
if (txn_db_options.write_policy == WRITE_COMMITTED &&
db_options.unordered_write) {
return Status::NotSupported(
"WRITE_COMMITTED is incompatible with unordered_writes");
}
if (txn_db_options.write_policy == WRITE_UNPREPARED &&
db_options.unordered_write) {
// TODO(lth): support it
return Status::NotSupported(
"WRITE_UNPREPARED is currently incompatible with unordered_writes");
}
std::vector<ColumnFamilyDescriptor> column_families_copy = column_families;
std::vector<size_t> compaction_enabled_cf_indices;
DBOptions db_options_2pc = db_options;
PrepareWrap(&db_options_2pc, &column_families_copy,
&compaction_enabled_cf_indices);
const bool use_seq_per_batch =
txn_db_options.write_policy == WRITE_PREPARED ||
txn_db_options.write_policy == WRITE_UNPREPARED;
const bool use_batch_per_txn =
txn_db_options.write_policy == WRITE_COMMITTED ||
txn_db_options.write_policy == WRITE_PREPARED;
s = DBImpl::Open(db_options_2pc, dbname, column_families_copy, handles, &db,
use_seq_per_batch, use_batch_per_txn);
if (s.ok()) {
ROCKS_LOG_WARN(db->GetDBOptions().info_log,
"Transaction write_policy is %" PRId32,
static_cast<int>(txn_db_options.write_policy));
s = WrapDB(db, txn_db_options, compaction_enabled_cf_indices, *handles,
dbptr);
}
if (!s.ok()) {
// just in case it was not deleted (and not set to nullptr).
delete db;
}
return s;
}
void TransactionDB::PrepareWrap(
DBOptions* db_options, std::vector<ColumnFamilyDescriptor>* column_families,
std::vector<size_t>* compaction_enabled_cf_indices) {
compaction_enabled_cf_indices->clear();
// Enable MemTable History if not already enabled
for (size_t i = 0; i < column_families->size(); i++) {
ColumnFamilyOptions* cf_options = &(*column_families)[i].options;
if (cf_options->max_write_buffer_number_to_maintain == 0) {
// Setting to -1 will set the History size to max_write_buffer_number.
cf_options->max_write_buffer_number_to_maintain = -1;
}
if (!cf_options->disable_auto_compactions) {
// Disable compactions momentarily to prevent race with DB::Open
cf_options->disable_auto_compactions = true;
compaction_enabled_cf_indices->push_back(i);
}
}
db_options->allow_2pc = true;
}
Status TransactionDB::WrapDB(
// make sure this db is already opened with memtable history enabled,
// auto compaction distabled and 2 phase commit enabled
DB* db, const TransactionDBOptions& txn_db_options,
const std::vector<size_t>& compaction_enabled_cf_indices,
const std::vector<ColumnFamilyHandle*>& handles, TransactionDB** dbptr) {
assert(db != nullptr);
assert(dbptr != nullptr);
*dbptr = nullptr;
std::unique_ptr<PessimisticTransactionDB> txn_db;
switch (txn_db_options.write_policy) {
case WRITE_UNPREPARED:
txn_db.reset(new WriteUnpreparedTxnDB(
db, PessimisticTransactionDB::ValidateTxnDBOptions(txn_db_options)));
break;
case WRITE_PREPARED:
txn_db.reset(new WritePreparedTxnDB(
db, PessimisticTransactionDB::ValidateTxnDBOptions(txn_db_options)));
break;
case WRITE_COMMITTED:
default:
txn_db.reset(new WriteCommittedTxnDB(
db, PessimisticTransactionDB::ValidateTxnDBOptions(txn_db_options)));
}
txn_db->UpdateCFComparatorMap(handles);
Status s = txn_db->Initialize(compaction_enabled_cf_indices, handles);
// In case of a failure at this point, db is deleted via the txn_db destructor
// and set to nullptr.
if (s.ok()) {
*dbptr = txn_db.release();
}
return s;
}
Status TransactionDB::WrapStackableDB(
// make sure this stackable_db is already opened with memtable history
// enabled, auto compaction distabled and 2 phase commit enabled
StackableDB* db, const TransactionDBOptions& txn_db_options,
const std::vector<size_t>& compaction_enabled_cf_indices,
const std::vector<ColumnFamilyHandle*>& handles, TransactionDB** dbptr) {
assert(db != nullptr);
assert(dbptr != nullptr);
*dbptr = nullptr;
std::unique_ptr<PessimisticTransactionDB> txn_db;
switch (txn_db_options.write_policy) {
case WRITE_UNPREPARED:
txn_db.reset(new WriteUnpreparedTxnDB(
db, PessimisticTransactionDB::ValidateTxnDBOptions(txn_db_options)));
break;
case WRITE_PREPARED:
txn_db.reset(new WritePreparedTxnDB(
db, PessimisticTransactionDB::ValidateTxnDBOptions(txn_db_options)));
break;
case WRITE_COMMITTED:
default:
txn_db.reset(new WriteCommittedTxnDB(
db, PessimisticTransactionDB::ValidateTxnDBOptions(txn_db_options)));
}
txn_db->UpdateCFComparatorMap(handles);
Status s = txn_db->Initialize(compaction_enabled_cf_indices, handles);
// In case of a failure at this point, db is deleted via the txn_db destructor
// and set to nullptr.
if (s.ok()) {
*dbptr = txn_db.release();
}
return s;
}
// Let TransactionLockMgr know that this column family exists so it can
// allocate a LockMap for it.
void PessimisticTransactionDB::AddColumnFamily(
const ColumnFamilyHandle* handle) {
lock_mgr_.AddColumnFamily(handle->GetID());
}
Status PessimisticTransactionDB::CreateColumnFamily(
const ColumnFamilyOptions& options, const std::string& column_family_name,
ColumnFamilyHandle** handle) {
InstrumentedMutexLock l(&column_family_mutex_);
Status s = VerifyCFOptions(options);
if (!s.ok()) {
return s;
}
s = db_->CreateColumnFamily(options, column_family_name, handle);
if (s.ok()) {
lock_mgr_.AddColumnFamily((*handle)->GetID());
UpdateCFComparatorMap(*handle);
}
return s;
}
// Let TransactionLockMgr know that it can deallocate the LockMap for this
// column family.
Status PessimisticTransactionDB::DropColumnFamily(
ColumnFamilyHandle* column_family) {
InstrumentedMutexLock l(&column_family_mutex_);
Status s = db_->DropColumnFamily(column_family);
if (s.ok()) {
lock_mgr_.RemoveColumnFamily(column_family->GetID());
}
return s;
}
Status PessimisticTransactionDB::TryLock(PessimisticTransaction* txn,
uint32_t cfh_id,
const std::string& key,
bool exclusive) {
return lock_mgr_.TryLock(txn, cfh_id, key, GetEnv(), exclusive);
}
void PessimisticTransactionDB::UnLock(PessimisticTransaction* txn,
const TransactionKeyMap* keys) {
lock_mgr_.UnLock(txn, keys, GetEnv());
}
void PessimisticTransactionDB::UnLock(PessimisticTransaction* txn,
uint32_t cfh_id, const std::string& key) {
lock_mgr_.UnLock(txn, cfh_id, key, GetEnv());
}
// Used when wrapping DB write operations in a transaction
Transaction* PessimisticTransactionDB::BeginInternalTransaction(
const WriteOptions& options) {
TransactionOptions txn_options;
Transaction* txn = BeginTransaction(options, txn_options, nullptr);
// Use default timeout for non-transactional writes
txn->SetLockTimeout(txn_db_options_.default_lock_timeout);
return txn;
}
// All user Put, Merge, Delete, and Write requests must be intercepted to make
// sure that they lock all keys that they are writing to avoid causing conflicts
// with any concurrent transactions. The easiest way to do this is to wrap all
// write operations in a transaction.
//
// Put(), Merge(), and Delete() only lock a single key per call. Write() will
// sort its keys before locking them. This guarantees that TransactionDB write
// methods cannot deadlock with each other (but still could deadlock with a
// Transaction).
Status PessimisticTransactionDB::Put(const WriteOptions& options,
ColumnFamilyHandle* column_family,
const Slice& key, const Slice& val) {
Status s;
Transaction* txn = BeginInternalTransaction(options);
txn->DisableIndexing();
// Since the client didn't create a transaction, they don't care about
// conflict checking for this write. So we just need to do PutUntracked().
s = txn->PutUntracked(column_family, key, val);
if (s.ok()) {
s = txn->Commit();
}
delete txn;
return s;
}
Status PessimisticTransactionDB::Delete(const WriteOptions& wopts,
ColumnFamilyHandle* column_family,
const Slice& key) {
Status s;
Transaction* txn = BeginInternalTransaction(wopts);
txn->DisableIndexing();
// Since the client didn't create a transaction, they don't care about
// conflict checking for this write. So we just need to do
// DeleteUntracked().
s = txn->DeleteUntracked(column_family, key);
if (s.ok()) {
s = txn->Commit();
}
delete txn;
return s;
}
Status PessimisticTransactionDB::SingleDelete(const WriteOptions& wopts,
ColumnFamilyHandle* column_family,
const Slice& key) {
Status s;
Transaction* txn = BeginInternalTransaction(wopts);
txn->DisableIndexing();
// Since the client didn't create a transaction, they don't care about
// conflict checking for this write. So we just need to do
// SingleDeleteUntracked().
s = txn->SingleDeleteUntracked(column_family, key);
if (s.ok()) {
s = txn->Commit();
}
delete txn;
return s;
}
Status PessimisticTransactionDB::Merge(const WriteOptions& options,
ColumnFamilyHandle* column_family,
const Slice& key, const Slice& value) {
Status s;
Transaction* txn = BeginInternalTransaction(options);
txn->DisableIndexing();
// Since the client didn't create a transaction, they don't care about
// conflict checking for this write. So we just need to do
// MergeUntracked().
s = txn->MergeUntracked(column_family, key, value);
if (s.ok()) {
s = txn->Commit();
}
delete txn;
return s;
}
Status PessimisticTransactionDB::Write(const WriteOptions& opts,
WriteBatch* updates) {
// Need to lock all keys in this batch to prevent write conflicts with
// concurrent transactions.
Transaction* txn = BeginInternalTransaction(opts);
txn->DisableIndexing();
auto txn_impl =
static_cast_with_check<PessimisticTransaction, Transaction>(txn);
// Since commitBatch sorts the keys before locking, concurrent Write()
// operations will not cause a deadlock.
// In order to avoid a deadlock with a concurrent Transaction, Transactions
// should use a lock timeout.
Status s = txn_impl->CommitBatch(updates);
delete txn;
return s;
}
Status WriteCommittedTxnDB::Write(
const WriteOptions& opts,
const TransactionDBWriteOptimizations& optimizations, WriteBatch* updates) {
if (optimizations.skip_concurrency_control) {
return db_impl_->Write(opts, updates);
} else {
return Write(opts, updates);
}
}
void PessimisticTransactionDB::InsertExpirableTransaction(
TransactionID tx_id, PessimisticTransaction* tx) {
assert(tx->GetExpirationTime() > 0);
std::lock_guard<std::mutex> lock(map_mutex_);
expirable_transactions_map_.insert({tx_id, tx});
}
void PessimisticTransactionDB::RemoveExpirableTransaction(TransactionID tx_id) {
std::lock_guard<std::mutex> lock(map_mutex_);
expirable_transactions_map_.erase(tx_id);
}
bool PessimisticTransactionDB::TryStealingExpiredTransactionLocks(
TransactionID tx_id) {
std::lock_guard<std::mutex> lock(map_mutex_);
auto tx_it = expirable_transactions_map_.find(tx_id);
if (tx_it == expirable_transactions_map_.end()) {
return true;
}
PessimisticTransaction& tx = *(tx_it->second);
return tx.TryStealingLocks();
}
void PessimisticTransactionDB::ReinitializeTransaction(
Transaction* txn, const WriteOptions& write_options,
const TransactionOptions& txn_options) {
auto txn_impl =
static_cast_with_check<PessimisticTransaction, Transaction>(txn);
txn_impl->Reinitialize(this, write_options, txn_options);
}
Transaction* PessimisticTransactionDB::GetTransactionByName(
const TransactionName& name) {
std::lock_guard<std::mutex> lock(name_map_mutex_);
auto it = transactions_.find(name);
if (it == transactions_.end()) {
return nullptr;
} else {
return it->second;
}
}
void PessimisticTransactionDB::GetAllPreparedTransactions(
std::vector<Transaction*>* transv) {
assert(transv);
transv->clear();
std::lock_guard<std::mutex> lock(name_map_mutex_);
for (auto it = transactions_.begin(); it != transactions_.end(); ++it) {
if (it->second->GetState() == Transaction::PREPARED) {
transv->push_back(it->second);
}
}
}
TransactionLockMgr::LockStatusData
PessimisticTransactionDB::GetLockStatusData() {
return lock_mgr_.GetLockStatusData();
}
std::vector<DeadlockPath> PessimisticTransactionDB::GetDeadlockInfoBuffer() {
return lock_mgr_.GetDeadlockInfoBuffer();
}
void PessimisticTransactionDB::SetDeadlockInfoBufferSize(uint32_t target_size) {
lock_mgr_.Resize(target_size);
}
void PessimisticTransactionDB::RegisterTransaction(Transaction* txn) {
assert(txn);
assert(txn->GetName().length() > 0);
assert(GetTransactionByName(txn->GetName()) == nullptr);
assert(txn->GetState() == Transaction::STARTED);
std::lock_guard<std::mutex> lock(name_map_mutex_);
transactions_[txn->GetName()] = txn;
}
void PessimisticTransactionDB::UnregisterTransaction(Transaction* txn) {
assert(txn);
std::lock_guard<std::mutex> lock(name_map_mutex_);
auto it = transactions_.find(txn->GetName());
assert(it != transactions_.end());
transactions_.erase(it);
}
} // namespace rocksdb
#endif // ROCKSDB_LITE