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/**
* Copyright (C) 2018-present MongoDB, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* <http://www.mongodb.com/licensing/server-side-public-license>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the Server Side Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kStorage
#include "mongo/platform/basic.h"
#include "mongo/db/storage/wiredtiger/wiredtiger_recovery_unit.h"
#include "mongo/bson/bsonobjbuilder.h"
#include "mongo/db/server_options.h"
#include "mongo/db/storage/wiredtiger/wiredtiger_begin_transaction_block.h"
#include "mongo/db/storage/wiredtiger/wiredtiger_kv_engine.h"
#include "mongo/db/storage/wiredtiger/wiredtiger_prepare_conflict.h"
#include "mongo/db/storage/wiredtiger/wiredtiger_session_cache.h"
#include "mongo/db/storage/wiredtiger/wiredtiger_util.h"
#include "mongo/util/hex.h"
#include "mongo/util/log.h"
namespace mongo {
namespace {
// Always notifies prepare conflict waiters when a transaction commits or aborts, even when the
// transaction is not prepared. This should always be enabled if WTPrepareConflictForReads is
// used, which fails randomly. If this is not enabled, no prepare conflicts will be resolved,
// because the recovery unit may not ever actually be in a prepared state.
MONGO_FAIL_POINT_DEFINE(WTAlwaysNotifyPrepareConflictWaiters);
logger::LogSeverity kSlowTransactionSeverity = logger::LogSeverity::Debug(1);
} // namespace
using Section = WiredTigerOperationStats::Section;
std::map<int, std::pair<StringData, Section>> WiredTigerOperationStats::_statNameMap = {
{WT_STAT_SESSION_BYTES_READ, std::make_pair("bytesRead"_sd, Section::DATA)},
{WT_STAT_SESSION_BYTES_WRITE, std::make_pair("bytesWritten"_sd, Section::DATA)},
{WT_STAT_SESSION_LOCK_DHANDLE_WAIT, std::make_pair("handleLock"_sd, Section::WAIT)},
{WT_STAT_SESSION_READ_TIME, std::make_pair("timeReadingMicros"_sd, Section::DATA)},
{WT_STAT_SESSION_WRITE_TIME, std::make_pair("timeWritingMicros"_sd, Section::DATA)},
{WT_STAT_SESSION_LOCK_SCHEMA_WAIT, std::make_pair("schemaLock"_sd, Section::WAIT)},
{WT_STAT_SESSION_CACHE_TIME, std::make_pair("cache"_sd, Section::WAIT)}};
std::shared_ptr<StorageStats> WiredTigerOperationStats::getCopy() {
std::shared_ptr<WiredTigerOperationStats> copy = std::make_shared<WiredTigerOperationStats>();
*copy += *this;
return copy;
}
void WiredTigerOperationStats::fetchStats(WT_SESSION* session,
const std::string& uri,
const std::string& config) {
invariant(session);
WT_CURSOR* c = nullptr;
const char* cursorConfig = config.empty() ? nullptr : config.c_str();
int ret = session->open_cursor(session, uri.c_str(), nullptr, cursorConfig, &c);
uassert(ErrorCodes::CursorNotFound, "Unable to open statistics cursor", ret == 0);
invariant(c);
ON_BLOCK_EXIT([&] { c->close(c); });
const char* desc;
uint64_t value;
int32_t key;
while (c->next(c) == 0 && c->get_key(c, &key) == 0) {
fassert(51035, c->get_value(c, &desc, nullptr, &value) == 0);
_stats[key] = WiredTigerUtil::castStatisticsValue<long long>(value);
}
// Reset the statistics so that the next fetch gives the recent values.
invariantWTOK(c->reset(c));
}
BSONObj WiredTigerOperationStats::toBSON() {
BSONObjBuilder bob;
std::unique_ptr<BSONObjBuilder> dataSection;
std::unique_ptr<BSONObjBuilder> waitSection;
for (auto const& stat : _stats) {
// Find the user consumable name for this statistic.
auto statIt = _statNameMap.find(stat.first);
invariant(statIt != _statNameMap.end());
auto statName = statIt->second.first;
Section subs = statIt->second.second;
long long val = stat.second;
// Add this statistic only if higher than zero.
if (val > 0) {
// Gather the statistic into its own subsection in the BSONObj.
switch (subs) {
case Section::DATA:
if (!dataSection)
dataSection = std::make_unique<BSONObjBuilder>();
dataSection->append(statName, val);
break;
case Section::WAIT:
if (!waitSection)
waitSection = std::make_unique<BSONObjBuilder>();
waitSection->append(statName, val);
break;
default:
MONGO_UNREACHABLE;
}
}
}
if (dataSection)
bob.append("data", dataSection->obj());
if (waitSection)
bob.append("timeWaitingMicros", waitSection->obj());
return bob.obj();
}
WiredTigerOperationStats& WiredTigerOperationStats::operator+=(
const WiredTigerOperationStats& other) {
for (auto const& otherStat : other._stats) {
_stats[otherStat.first] += otherStat.second;
}
return (*this);
}
StorageStats& WiredTigerOperationStats::operator+=(const StorageStats& other) {
*this += checked_cast<const WiredTigerOperationStats&>(other);
return (*this);
}
WiredTigerRecoveryUnit::WiredTigerRecoveryUnit(WiredTigerSessionCache* sc)
: WiredTigerRecoveryUnit(sc, sc->getKVEngine()->getOplogManager()) {}
WiredTigerRecoveryUnit::WiredTigerRecoveryUnit(WiredTigerSessionCache* sc,
WiredTigerOplogManager* oplogManager)
: _sessionCache(sc), _oplogManager(oplogManager) {}
WiredTigerRecoveryUnit::~WiredTigerRecoveryUnit() {
invariant(!_inUnitOfWork(), toString(_getState()));
_abort();
}
void WiredTigerRecoveryUnit::_commit() {
// Since we cannot have both a _lastTimestampSet and a _commitTimestamp, we set the
// commit time as whichever is non-empty. If both are empty, then _lastTimestampSet will
// be boost::none and we'll set the commit time to that.
auto commitTime = _commitTimestamp.isNull() ? _lastTimestampSet : _commitTimestamp;
bool notifyDone = !_prepareTimestamp.isNull();
if (_session && _isActive()) {
_txnClose(true);
}
_setState(State::kCommitting);
if (MONGO_unlikely(WTAlwaysNotifyPrepareConflictWaiters.shouldFail())) {
notifyDone = true;
}
if (notifyDone) {
_sessionCache->notifyPreparedUnitOfWorkHasCommittedOrAborted();
}
commitRegisteredChanges(commitTime);
_setState(State::kInactive);
}
void WiredTigerRecoveryUnit::_abort() {
bool notifyDone = !_prepareTimestamp.isNull();
if (_session && _isActive()) {
_txnClose(false);
}
_setState(State::kAborting);
if (notifyDone || MONGO_unlikely(WTAlwaysNotifyPrepareConflictWaiters.shouldFail())) {
_sessionCache->notifyPreparedUnitOfWorkHasCommittedOrAborted();
}
abortRegisteredChanges();
_setState(State::kInactive);
}
void WiredTigerRecoveryUnit::beginUnitOfWork(OperationContext* opCtx) {
invariant(!_inUnitOfWork(), toString(_getState()));
invariant(!_isCommittingOrAborting(),
str::stream() << "cannot begin unit of work while commit or rollback handlers are "
"running: "
<< toString(_getState()));
_setState(_isActive() ? State::kActive : State::kInactiveInUnitOfWork);
}
void WiredTigerRecoveryUnit::prepareUnitOfWork() {
invariant(_inUnitOfWork(), toString(_getState()));
invariant(!_prepareTimestamp.isNull());
auto session = getSession();
WT_SESSION* s = session->getSession();
LOG(1) << "preparing transaction at time: " << _prepareTimestamp;
const std::string conf = "prepare_timestamp=" + integerToHex(_prepareTimestamp.asULL());
// Prepare the transaction.
invariantWTOK(s->prepare_transaction(s, conf.c_str()));
}
void WiredTigerRecoveryUnit::doCommitUnitOfWork() {
invariant(_inUnitOfWork(), toString(_getState()));
_commit();
}
void WiredTigerRecoveryUnit::doAbortUnitOfWork() {
invariant(_inUnitOfWork(), toString(_getState()));
_abort();
}
void WiredTigerRecoveryUnit::_ensureSession() {
if (!_session) {
_session = _sessionCache->getSession();
}
}
bool WiredTigerRecoveryUnit::waitUntilDurable(OperationContext* opCtx) {
invariant(!_inUnitOfWork(), toString(_getState()));
invariant(!opCtx->lockState()->isLocked() || storageGlobalParams.repair);
// Flushes the journal log to disk. Checkpoints all data if journaling is disabled.
_sessionCache->waitUntilDurable(opCtx,
WiredTigerSessionCache::Fsync::kJournal,
WiredTigerSessionCache::UseJournalListener::kUpdate);
return true;
}
bool WiredTigerRecoveryUnit::waitUntilUnjournaledWritesDurable(OperationContext* opCtx,
bool stableCheckpoint) {
invariant(!_inUnitOfWork(), toString(_getState()));
invariant(!opCtx->lockState()->isLocked() || storageGlobalParams.repair);
// Take a checkpoint, rather than only flush the (oplog) journal, in order to lock in stable
// writes to unjournaled tables.
//
// If 'stableCheckpoint' is set, then we will only checkpoint data up to and including the
// stable_timestamp set on WT at the time of the checkpoint. Otherwise, we will checkpoint all
// of the data.
WiredTigerSessionCache::Fsync fsyncType = stableCheckpoint
? WiredTigerSessionCache::Fsync::kCheckpointStableTimestamp
: WiredTigerSessionCache::Fsync::kCheckpointAll;
_sessionCache->waitUntilDurable(
opCtx, fsyncType, WiredTigerSessionCache::UseJournalListener::kUpdate);
return true;
}
void WiredTigerRecoveryUnit::assertInActiveTxn() const {
if (_isActive()) {
return;
}
severe() << "Recovery unit is not active. Current state: " << toString(_getState());
fassertFailed(28575);
}
boost::optional<int64_t> WiredTigerRecoveryUnit::getOplogVisibilityTs() {
if (!_isOplogReader) {
return boost::none;
}
getSession();
return _oplogVisibleTs;
}
WiredTigerSession* WiredTigerRecoveryUnit::getSession() {
if (!_isActive()) {
_txnOpen();
_setState(_inUnitOfWork() ? State::kActive : State::kActiveNotInUnitOfWork);
}
return _session.get();
}
WiredTigerSession* WiredTigerRecoveryUnit::getSessionNoTxn() {
_ensureSession();
WiredTigerSession* session = _session.get();
// Handling queued drops can be slow, which is not desired for internal operations like FTDC
// sampling. Disable handling of queued drops for such sessions.
session->dropQueuedIdentsAtSessionEndAllowed(false);
return session;
}
void WiredTigerRecoveryUnit::doAbandonSnapshot() {
invariant(!_inUnitOfWork(), toString(_getState()));
if (_isActive()) {
// Can't be in a WriteUnitOfWork, so safe to rollback
_txnClose(false);
}
_setState(State::kInactive);
}
void WiredTigerRecoveryUnit::preallocateSnapshot() {
// Begin a new transaction, if one is not already started.
getSession();
}
void WiredTigerRecoveryUnit::_txnClose(bool commit) {
invariant(_isActive(), toString(_getState()));
WT_SESSION* s = _session->getSession();
if (_timer) {
const int transactionTime = _timer->millis();
// `serverGlobalParams.slowMs` can be set to values <= 0. In those cases, give logging a
// break.
if (transactionTime >= std::max(1, serverGlobalParams.slowMS)) {
LOG(kSlowTransactionSeverity)
<< "Slow WT transaction. Lifetime of SnapshotId " << getSnapshotId().toNumber()
<< " was " << transactionTime << "ms";
}
}
int wtRet;
if (commit) {
StringBuilder conf;
if (!_commitTimestamp.isNull()) {
// There is currently no scenario where it is intentional to commit before the current
// read timestamp.
invariant(_readAtTimestamp.isNull() || _commitTimestamp >= _readAtTimestamp);
conf << "commit_timestamp=" << integerToHex(_commitTimestamp.asULL()) << ",";
_isTimestamped = true;
}
if (!_durableTimestamp.isNull()) {
conf << "durable_timestamp=" << integerToHex(_durableTimestamp.asULL());
}
if (_mustBeTimestamped) {
invariant(_isTimestamped);
}
wtRet = s->commit_transaction(s, conf.str().c_str());
LOG(3) << "WT commit_transaction for snapshot id " << getSnapshotId().toNumber();
} else {
wtRet = s->rollback_transaction(s, nullptr);
invariant(!wtRet);
LOG(3) << "WT rollback_transaction for snapshot id " << getSnapshotId().toNumber();
}
if (_isTimestamped) {
if (!_orderedCommit) {
// We only need to update oplog visibility where commits can be out-of-order with
// respect to their assigned optime. This will ensure the oplog read timestamp gets
// updated when oplog 'holes' are filled: the last commit filling the last hole will
// prompt the oplog read timestamp to be forwarded.
//
// This should happen only on primary nodes.
_oplogManager->triggerOplogVisibilityUpdate();
}
_isTimestamped = false;
}
invariantWTOK(wtRet);
invariant(!_lastTimestampSet || _commitTimestamp.isNull(),
str::stream() << "Cannot have both a _lastTimestampSet and a "
"_commitTimestamp. _lastTimestampSet: "
<< _lastTimestampSet->toString()
<< ". _commitTimestamp: " << _commitTimestamp.toString());
// We reset the _lastTimestampSet between transactions. Since it is legal for one
// transaction on a RecoveryUnit to call setTimestamp() and another to call
// setCommitTimestamp().
_lastTimestampSet = boost::none;
_prepareTimestamp = Timestamp();
_durableTimestamp = Timestamp();
_catalogConflictTimestamp = Timestamp();
_roundUpPreparedTimestamps = RoundUpPreparedTimestamps::kNoRound;
_isOplogReader = false;
_oplogVisibleTs = boost::none;
_orderedCommit = true; // Default value is true; we assume all writes are ordered.
_mustBeTimestamped = false;
}
Status WiredTigerRecoveryUnit::obtainMajorityCommittedSnapshot() {
invariant(_timestampReadSource == ReadSource::kMajorityCommitted);
auto snapshotName = _sessionCache->snapshotManager().getMinSnapshotForNextCommittedRead();
if (!snapshotName) {
return {ErrorCodes::ReadConcernMajorityNotAvailableYet,
"Read concern majority reads are currently not possible."};
}
_majorityCommittedSnapshot = *snapshotName;
return Status::OK();
}
boost::optional<Timestamp> WiredTigerRecoveryUnit::getPointInTimeReadTimestamp() {
// After a ReadSource has been set on this RecoveryUnit, callers expect that this method returns
// the read timestamp that will be used for current or future transactions. Because callers use
// this timestamp to inform visiblity of operations, it is therefore necessary to open a
// transaction to establish a read timestamp, but only for ReadSources that are expected to have
// read timestamps.
switch (_timestampReadSource) {
case ReadSource::kUnset:
case ReadSource::kNoTimestamp:
case ReadSource::kCheckpoint:
return boost::none;
case ReadSource::kMajorityCommitted:
// This ReadSource depends on a previous call to obtainMajorityCommittedSnapshot() and
// does not require an open transaction to return a valid timestamp.
invariant(!_majorityCommittedSnapshot.isNull());
return _majorityCommittedSnapshot;
case ReadSource::kProvided:
// The read timestamp is set by the user and does not require a transaction to be open.
invariant(!_readAtTimestamp.isNull());
return _readAtTimestamp;
// The following ReadSources can only establish a read timestamp when a transaction is
// opened.
case ReadSource::kNoOverlap:
case ReadSource::kLastApplied:
case ReadSource::kAllDurableSnapshot:
break;
}
// Ensure a transaction is opened.
getSession();
switch (_timestampReadSource) {
case ReadSource::kLastApplied:
// The lastApplied timestamp is not always available, so it is not possible to invariant
// that it exists as other ReadSources do.
if (!_readAtTimestamp.isNull()) {
return _readAtTimestamp;
}
return boost::none;
case ReadSource::kNoOverlap:
case ReadSource::kAllDurableSnapshot:
invariant(!_readAtTimestamp.isNull());
return _readAtTimestamp;
// The follow ReadSources returned values in the first switch block.
case ReadSource::kUnset:
case ReadSource::kNoTimestamp:
case ReadSource::kMajorityCommitted:
case ReadSource::kProvided:
case ReadSource::kCheckpoint:
MONGO_UNREACHABLE;
}
MONGO_UNREACHABLE;
}
void WiredTigerRecoveryUnit::_txnOpen() {
invariant(!_isActive(), toString(_getState()));
invariant(!_isCommittingOrAborting(),
str::stream() << "commit or rollback handler reopened transaction: "
<< toString(_getState()));
_ensureSession();
// Only start a timer for transaction's lifetime if we're going to log it.
if (shouldLog(kSlowTransactionSeverity)) {
_timer.reset(new Timer());
}
WT_SESSION* session = _session->getSession();
switch (_timestampReadSource) {
case ReadSource::kUnset:
case ReadSource::kNoTimestamp: {
if (_isOplogReader) {
_oplogVisibleTs = static_cast<std::int64_t>(_oplogManager->getOplogReadTimestamp());
}
WiredTigerBeginTxnBlock(session, _prepareConflictBehavior, _roundUpPreparedTimestamps)
.done();
break;
}
case ReadSource::kCheckpoint: {
WiredTigerBeginTxnBlock(session, _prepareConflictBehavior, _roundUpPreparedTimestamps)
.done();
break;
}
case ReadSource::kMajorityCommitted: {
// We reset _majorityCommittedSnapshot to the actual read timestamp used when the
// transaction was started.
_majorityCommittedSnapshot =
_sessionCache->snapshotManager().beginTransactionOnCommittedSnapshot(
session, _prepareConflictBehavior, _roundUpPreparedTimestamps);
break;
}
case ReadSource::kLastApplied: {
if (_sessionCache->snapshotManager().getLocalSnapshot()) {
_readAtTimestamp = _sessionCache->snapshotManager().beginTransactionOnLocalSnapshot(
session, _prepareConflictBehavior, _roundUpPreparedTimestamps);
} else {
WiredTigerBeginTxnBlock(
session, _prepareConflictBehavior, _roundUpPreparedTimestamps)
.done();
}
break;
}
case ReadSource::kNoOverlap: {
_readAtTimestamp = _beginTransactionAtNoOverlapTimestamp(session);
break;
}
case ReadSource::kAllDurableSnapshot: {
if (_readAtTimestamp.isNull()) {
_readAtTimestamp = _beginTransactionAtAllDurableTimestamp(session);
break;
}
// Intentionally continue to the next case to read at the _readAtTimestamp.
}
case ReadSource::kProvided: {
WiredTigerBeginTxnBlock txnOpen(
session, _prepareConflictBehavior, _roundUpPreparedTimestamps);
auto status = txnOpen.setReadSnapshot(_readAtTimestamp);
if (!status.isOK() && status.code() == ErrorCodes::BadValue) {
uasserted(ErrorCodes::SnapshotTooOld,
str::stream() << "Read timestamp " << _readAtTimestamp.toString()
<< " is older than the oldest available timestamp.");
}
uassertStatusOK(status);
txnOpen.done();
break;
}
}
LOG(3) << "WT begin_transaction for snapshot id " << getSnapshotId().toNumber();
}
Timestamp WiredTigerRecoveryUnit::_beginTransactionAtAllDurableTimestamp(WT_SESSION* session) {
WiredTigerBeginTxnBlock txnOpen(session,
_prepareConflictBehavior,
_roundUpPreparedTimestamps,
RoundUpReadTimestamp::kRound);
Timestamp txnTimestamp = Timestamp(_oplogManager->fetchAllDurableValue(session->connection));
auto status = txnOpen.setReadSnapshot(txnTimestamp);
fassert(50948, status);
// Since this is not in a critical section, we might have rounded to oldest between
// calling getAllDurable and setReadSnapshot. We need to get the actual read timestamp we
// used.
auto readTimestamp = _getTransactionReadTimestamp(session);
txnOpen.done();
return readTimestamp;
}
Timestamp WiredTigerRecoveryUnit::_beginTransactionAtNoOverlapTimestamp(WT_SESSION* session) {
auto lastApplied = _sessionCache->snapshotManager().getLocalSnapshot();
Timestamp allDurable = Timestamp(_oplogManager->fetchAllDurableValue(session->connection));
// When using timestamps for reads and writes, it's important that readers and writers don't
// overlap with the timestamps they use. In other words, at any point in the system there should
// be a timestamp T such that writers only commit at times greater than T and readers only read
// at, or earlier than T. This time T is called the no-overlap point. Using the `kNoOverlap`
// ReadSource will compute the most recent known time that is safe to read at.
// The no-overlap point is computed as the minimum of the storage engine's all_durable time
// and replication's last applied time. On primaries, the last applied time is updated as
// transactions commit, which is not necessarily in the order they appear in the oplog. Thus
// the all_durable time is an appropriate value to read at.
// On secondaries, however, the all_durable time, as computed by the storage engine, can
// advance before oplog application completes a batch. This is because the all_durable time
// is only computed correctly if the storage engine is informed of commit timestamps in
// increasing order. Because oplog application processes a batch of oplog entries out of order,
// the timestamping requirement is not satisfied. Secondaries, however, only update the last
// applied time after a batch completes. Thus last applied is a valid no-overlap point on
// secondaries.
// By taking the minimum of the two values, storage can compute a legal time to read at without
// knowledge of the replication state. The no-overlap point is the minimum of the all_durable
// time, which represents the point where no transactions will commit any earlier, and
// lastApplied, which represents the highest optime a node has applied, a point no readers
// should read afterward.
Timestamp readTimestamp = (lastApplied) ? std::min(*lastApplied, allDurable) : allDurable;
WiredTigerBeginTxnBlock txnOpen(session,
_prepareConflictBehavior,
_roundUpPreparedTimestamps,
RoundUpReadTimestamp::kRound);
auto status = txnOpen.setReadSnapshot(readTimestamp);
fassert(51066, status);
// We might have rounded to oldest between calling getAllDurable and setReadSnapshot. We need
// to get the actual read timestamp we used.
readTimestamp = _getTransactionReadTimestamp(session);
txnOpen.done();
return readTimestamp;
}
Timestamp WiredTigerRecoveryUnit::_getTransactionReadTimestamp(WT_SESSION* session) {
char buf[(2 * 8 /*bytes in hex*/) + 1 /*nul terminator*/];
auto wtstatus = session->query_timestamp(session, buf, "get=read");
invariantWTOK(wtstatus);
uint64_t read_timestamp;
fassert(50949, NumberParser().base(16)(buf, &read_timestamp));
return Timestamp(read_timestamp);
}
Status WiredTigerRecoveryUnit::setTimestamp(Timestamp timestamp) {
_ensureSession();
LOG(3) << "WT set timestamp of future write operations to " << timestamp;
WT_SESSION* session = _session->getSession();
invariant(_inUnitOfWork(), toString(_getState()));
invariant(_prepareTimestamp.isNull());
invariant(_commitTimestamp.isNull(),
str::stream() << "Commit timestamp set to " << _commitTimestamp.toString()
<< " and trying to set WUOW timestamp to " << timestamp.toString());
invariant(_readAtTimestamp.isNull() || timestamp >= _readAtTimestamp,
str::stream() << "future commit timestamp " << timestamp.toString()
<< " cannot be older than read timestamp "
<< _readAtTimestamp.toString());
_lastTimestampSet = timestamp;
// Starts the WT transaction associated with this session.
getSession();
const std::string conf = "commit_timestamp=" + integerToHex(timestamp.asULL());
auto rc = session->timestamp_transaction(session, conf.c_str());
if (rc == 0) {
_isTimestamped = true;
}
return wtRCToStatus(rc, "timestamp_transaction");
}
void WiredTigerRecoveryUnit::setCommitTimestamp(Timestamp timestamp) {
// This can be called either outside of a WriteUnitOfWork or in a prepared transaction after
// setPrepareTimestamp() is called. Prepared transactions ensure the correct timestamping
// semantics and the set-once commitTimestamp behavior is exactly what prepared transactions
// want.
invariant(!_inUnitOfWork() || !_prepareTimestamp.isNull(), toString(_getState()));
invariant(_commitTimestamp.isNull(),
str::stream() << "Commit timestamp set to " << _commitTimestamp.toString()
<< " and trying to set it to " << timestamp.toString());
invariant(!_lastTimestampSet,
str::stream() << "Last timestamp set is " << _lastTimestampSet->toString()
<< " and trying to set commit timestamp to " << timestamp.toString());
invariant(!_isTimestamped);
_commitTimestamp = timestamp;
}
Timestamp WiredTigerRecoveryUnit::getCommitTimestamp() const {
return _commitTimestamp;
}
void WiredTigerRecoveryUnit::setDurableTimestamp(Timestamp timestamp) {
invariant(
_durableTimestamp.isNull(),
str::stream() << "Trying to reset durable timestamp when it was already set. wasSetTo: "
<< _durableTimestamp.toString() << " setTo: " << timestamp.toString());
_durableTimestamp = timestamp;
}
Timestamp WiredTigerRecoveryUnit::getDurableTimestamp() const {
return _durableTimestamp;
}
void WiredTigerRecoveryUnit::clearCommitTimestamp() {
invariant(!_inUnitOfWork(), toString(_getState()));
invariant(!_commitTimestamp.isNull());
invariant(!_lastTimestampSet,
str::stream() << "Last timestamp set is " << _lastTimestampSet->toString()
<< " and trying to clear commit timestamp.");
invariant(!_isTimestamped);
_commitTimestamp = Timestamp();
}
void WiredTigerRecoveryUnit::setPrepareTimestamp(Timestamp timestamp) {
invariant(_inUnitOfWork(), toString(_getState()));
invariant(_prepareTimestamp.isNull(),
str::stream() << "Trying to set prepare timestamp to " << timestamp.toString()
<< ". It's already set to " << _prepareTimestamp.toString());
invariant(_commitTimestamp.isNull(),
str::stream() << "Commit timestamp is " << _commitTimestamp.toString()
<< " and trying to set prepare timestamp to " << timestamp.toString());
invariant(!_lastTimestampSet,
str::stream() << "Last timestamp set is " << _lastTimestampSet->toString()
<< " and trying to set prepare timestamp to " << timestamp.toString());
_prepareTimestamp = timestamp;
}
Timestamp WiredTigerRecoveryUnit::getPrepareTimestamp() const {
invariant(_inUnitOfWork(), toString(_getState()));
invariant(!_prepareTimestamp.isNull());
invariant(_commitTimestamp.isNull(),
str::stream() << "Commit timestamp is " << _commitTimestamp.toString()
<< " and trying to get prepare timestamp of "
<< _prepareTimestamp.toString());
invariant(!_lastTimestampSet,
str::stream() << "Last timestamp set is " << _lastTimestampSet->toString()
<< " and trying to get prepare timestamp of "
<< _prepareTimestamp.toString());
return _prepareTimestamp;
}
void WiredTigerRecoveryUnit::setPrepareConflictBehavior(PrepareConflictBehavior behavior) {
// If there is an open storage transaction, it is not valid to try to change the behavior of
// ignoring prepare conflicts, since that behavior is applied when the transaction is opened.
invariant(
!_isActive(),
str::stream() << "Current state: " << toString(_getState())
<< ". Invalid internal state while setting prepare conflict behavior to: "
<< static_cast<int>(behavior));
_prepareConflictBehavior = behavior;
}
PrepareConflictBehavior WiredTigerRecoveryUnit::getPrepareConflictBehavior() const {
return _prepareConflictBehavior;
}
void WiredTigerRecoveryUnit::setRoundUpPreparedTimestamps(bool value) {
// This cannot be called after WiredTigerRecoveryUnit::_txnOpen.
invariant(!_isActive(),
str::stream() << "Can't change round up prepared timestamps flag "
<< "when current state is " << toString(_getState()));
_roundUpPreparedTimestamps =
(value) ? RoundUpPreparedTimestamps::kRound : RoundUpPreparedTimestamps::kNoRound;
}
void WiredTigerRecoveryUnit::setTimestampReadSource(ReadSource readSource,
boost::optional<Timestamp> provided) {
LOG(3) << "setting timestamp read source: " << static_cast<int>(readSource)
<< ", provided timestamp: " << ((provided) ? provided->toString() : "none");
invariant(!_isActive() || _timestampReadSource == readSource,
str::stream() << "Current state: " << toString(_getState())
<< ". Invalid internal state while setting timestamp read source: "
<< static_cast<int>(readSource) << ", provided timestamp: "
<< (provided ? provided->toString() : "none"));
invariant(!provided == (readSource != ReadSource::kProvided));
invariant(!(provided && provided->isNull()));
_timestampReadSource = readSource;
_readAtTimestamp = (provided) ? *provided : Timestamp();
}
RecoveryUnit::ReadSource WiredTigerRecoveryUnit::getTimestampReadSource() const {
return _timestampReadSource;
}
void WiredTigerRecoveryUnit::beginIdle() {
// Close all cursors, we don't want to keep any old cached cursors around.
if (_session) {
_session->closeAllCursors("");
}
}
std::shared_ptr<StorageStats> WiredTigerRecoveryUnit::getOperationStatistics() const {
std::shared_ptr<WiredTigerOperationStats> statsPtr(nullptr);
if (!_session)
return statsPtr;
WT_SESSION* s = _session->getSession();
invariant(s);
statsPtr = std::make_shared<WiredTigerOperationStats>();
statsPtr->fetchStats(s, "statistics:session", "statistics=(fast)");
return statsPtr;
}
void WiredTigerRecoveryUnit::setCatalogConflictingTimestamp(Timestamp timestamp) {
// This cannot be called after a storage snapshot is allocated.
invariant(!_isActive(), toString(_getState()));
invariant(_timestampReadSource == ReadSource::kNoTimestamp,
str::stream() << "Illegal to set catalog conflicting timestamp for a read source "
<< static_cast<int>(_timestampReadSource));
invariant(_catalogConflictTimestamp.isNull(),
str::stream() << "Trying to set catalog conflicting timestamp to "
<< timestamp.toString() << ". It's already set to "
<< _catalogConflictTimestamp.toString());
invariant(!timestamp.isNull());
_catalogConflictTimestamp = timestamp;
}
Timestamp WiredTigerRecoveryUnit::getCatalogConflictingTimestamp() const {
return _catalogConflictTimestamp;
}
} // namespace mongo
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