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/**
* Copyright (C) 2008 10gen Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* 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
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* 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 GNU Affero General 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::kReplication
#include "mongo/platform/basic.h"
#include "mongo/platform/bits.h"
#include "mongo/db/repl/sync_tail.h"
#include <boost/functional/hash.hpp>
#include <boost/ref.hpp>
#include <memory>
#include "third_party/murmurhash3/MurmurHash3.h"
#include "mongo/base/counter.h"
#include "mongo/db/auth/authorization_session.h"
#include "mongo/db/catalog/collection.h"
#include "mongo/db/catalog/database.h"
#include "mongo/db/catalog/database_holder.h"
#include "mongo/db/catalog/document_validation.h"
#include "mongo/db/commands/fsync.h"
#include "mongo/db/commands/server_status_metric.h"
#include "mongo/db/concurrency/write_conflict_exception.h"
#include "mongo/db/curop.h"
#include "mongo/db/db_raii.h"
#include "mongo/db/service_context.h"
#include "mongo/db/operation_context_impl.h"
#include "mongo/db/prefetch.h"
#include "mongo/db/repl/bgsync.h"
#include "mongo/db/repl/minvalid.h"
#include "mongo/db/repl/oplog.h"
#include "mongo/db/repl/repl_client_info.h"
#include "mongo/db/repl/replica_set_config.h"
#include "mongo/db/repl/replication_coordinator_global.h"
#include "mongo/db/stats/timer_stats.h"
#include "mongo/util/exit.h"
#include "mongo/util/fail_point_service.h"
#include "mongo/util/log.h"
#include "mongo/util/mongoutils/str.h"
namespace mongo {
using std::endl;
namespace repl {
#if defined(MONGO_PLATFORM_64)
const int replWriterThreadCount = 16;
const int replPrefetcherThreadCount = 16;
#elif defined(MONGO_PLATFORM_32)
const int replWriterThreadCount = 2;
const int replPrefetcherThreadCount = 2;
#else
#error need to include something that defines MONGO_PLATFORM_XX
#endif
static Counter64 opsAppliedStats;
//The oplog entries applied
static ServerStatusMetricField<Counter64> displayOpsApplied( "repl.apply.ops",
&opsAppliedStats );
MONGO_FP_DECLARE(rsSyncApplyStop);
// Number and time of each ApplyOps worker pool round
static TimerStats applyBatchStats;
static ServerStatusMetricField<TimerStats> displayOpBatchesApplied(
"repl.apply.batches",
&applyBatchStats );
void initializePrefetchThread() {
if (!ClientBasic::getCurrent()) {
Client::initThreadIfNotAlready();
AuthorizationSession::get(cc())->grantInternalAuthorization();
}
}
namespace {
bool isCrudOpType( const char* field ) {
switch ( field[0] ) {
case 'd':
case 'i':
case 'u':
return field[1] == 0;
}
return false;
}
}
SyncTail::SyncTail(BackgroundSyncInterface *q, MultiSyncApplyFunc func) :
_networkQueue(q),
_applyFunc(func),
_writerPool(replWriterThreadCount, "repl writer worker "),
_prefetcherPool(replPrefetcherThreadCount, "repl prefetch worker ")
{}
SyncTail::~SyncTail() {}
bool SyncTail::peek(BSONObj* op) {
return _networkQueue->peek(op);
}
// static
Status SyncTail::syncApply(OperationContext* txn,
const BSONObj &op,
bool convertUpdateToUpsert,
ApplyOperationInLockFn applyOperationInLock,
ApplyCommandInLockFn applyCommandInLock,
IncrementOpsAppliedStatsFn incrementOpsAppliedStats) {
if (inShutdown()) {
return Status::OK();
}
// Count each log op application as a separate operation, for reporting purposes
CurOp::get(txn)->reset();
const char *ns = op.getStringField("ns");
verify(ns);
const char* opType = op["op"].valuestrsafe();
bool isCommand(opType[0] == 'c');
bool isNoOp(opType[0] == 'n');
if ( (*ns == '\0') || (*ns == '.') ) {
// this is ugly
// this is often a no-op
// but can't be 100% sure
if (!isNoOp) {
error() << "skipping bad op in oplog: " << op.toString();
}
return Status::OK();
}
if (isCommand) {
MONGO_WRITE_CONFLICT_RETRY_LOOP_BEGIN {
// a command may need a global write lock. so we will conservatively go
// ahead and grab one here. suboptimal. :-(
Lock::GlobalWrite globalWriteLock(txn->lockState());
// special case apply for commands to avoid implicit database creation
Status status = applyCommandInLock(txn, op);
incrementOpsAppliedStats();
return status;
} MONGO_WRITE_CONFLICT_RETRY_LOOP_END(txn, "syncApply_command", ns);
}
auto applyOp = [&](Database* db) {
// For non-initial-sync, we convert updates to upserts
// to suppress errors when replaying oplog entries.
txn->setReplicatedWrites(false);
DisableDocumentValidation validationDisabler(txn);
Status status = applyOperationInLock(txn, db, op, convertUpdateToUpsert);
incrementOpsAppliedStats();
return status;
};
if (isNoOp ||
(opType[0] == 'i' && nsToCollectionSubstring( ns ) == "system.indexes")) {
auto opStr = isNoOp ? "syncApply_noop" : "syncApply_indexBuild";
MONGO_WRITE_CONFLICT_RETRY_LOOP_BEGIN {
Lock::DBLock dbLock(txn->lockState(), nsToDatabaseSubstring(ns), MODE_X);
OldClientContext ctx(txn, ns);
return applyOp(ctx.db());
} MONGO_WRITE_CONFLICT_RETRY_LOOP_END(txn, opStr, ns);
}
if (isCrudOpType(opType)) {
MONGO_WRITE_CONFLICT_RETRY_LOOP_BEGIN {
// DB lock always acquires the global lock
std::unique_ptr<Lock::DBLock> dbLock;
std::unique_ptr<Lock::CollectionLock> collectionLock;
std::unique_ptr<OldClientContext> ctx;
auto dbName = nsToDatabaseSubstring(ns);
auto resetLocks = [&](LockMode mode) {
collectionLock.reset();
dbLock.reset(new Lock::DBLock(txn->lockState(), dbName, mode));
collectionLock.reset(new Lock::CollectionLock(txn->lockState(), ns, mode));
};
resetLocks(MODE_IX);
if (!dbHolder().get(txn, dbName)) {
// need to create database, try again
resetLocks(MODE_X);
ctx.reset(new OldClientContext(txn, ns));
}
else {
ctx.reset(new OldClientContext(txn, ns));
if (!ctx->db()->getCollection(ns)) {
// uh, oh, we need to create collection
// try again
ctx.reset();
resetLocks(MODE_X);
ctx.reset(new OldClientContext(txn, ns));
}
}
return applyOp(ctx->db());
} MONGO_WRITE_CONFLICT_RETRY_LOOP_END(txn, "syncApply_CRUD", ns);
}
// unknown opType
str::stream ss;
ss << "bad opType '" << opType << "' in oplog entry: " << op.toString();
error() << std::string(ss);
return Status(ErrorCodes::BadValue, ss);
}
Status SyncTail::syncApply(OperationContext* txn,
const BSONObj &op,
bool convertUpdateToUpsert) {
return syncApply(txn,
op,
convertUpdateToUpsert,
applyOperation_inlock,
applyCommand_inlock,
stdx::bind(&Counter64::increment, &opsAppliedStats, 1ULL));
}
namespace {
// The pool threads call this to prefetch each op
void prefetchOp(const BSONObj& op) {
initializePrefetchThread();
const char *ns = op.getStringField("ns");
if (ns && (ns[0] != '\0')) {
try {
// one possible tweak here would be to stay in the read lock for this database
// for multiple prefetches if they are for the same database.
OperationContextImpl txn;
AutoGetCollectionForRead ctx(&txn, ns);
Database* db = ctx.getDb();
if (db) {
prefetchPagesForReplicatedOp(&txn, db, op);
}
}
catch (const DBException& e) {
LOG(2) << "ignoring exception in prefetchOp(): " << e.what() << endl;
}
catch (const std::exception& e) {
log() << "Unhandled std::exception in prefetchOp(): " << e.what() << endl;
fassertFailed(16397);
}
}
}
// Doles out all the work to the reader pool threads and waits for them to complete
void prefetchOps(const std::deque<BSONObj>& ops,
threadpool::ThreadPool* prefetcherPool) {
invariant(prefetcherPool);
for (std::deque<BSONObj>::const_iterator it = ops.begin();
it != ops.end();
++it) {
prefetcherPool->schedule(&prefetchOp, *it);
}
prefetcherPool->join();
}
// Doles out all the work to the writer pool threads and waits for them to complete
void applyOps(const std::vector< std::vector<BSONObj> >& writerVectors,
threadpool::ThreadPool* writerPool,
SyncTail::MultiSyncApplyFunc func,
SyncTail* sync) {
TimerHolder timer(&applyBatchStats);
for (std::vector< std::vector<BSONObj> >::const_iterator it = writerVectors.begin();
it != writerVectors.end();
++it) {
if (!it->empty()) {
writerPool->schedule(func, boost::cref(*it), sync);
}
}
writerPool->join();
}
void fillWriterVectors(const std::deque<BSONObj>& ops,
std::vector< std::vector<BSONObj> >* writerVectors) {
for (std::deque<BSONObj>::const_iterator it = ops.begin();
it != ops.end();
++it) {
const BSONElement e = it->getField("ns");
verify(e.type() == String);
const char* ns = e.valuestr();
int len = e.valuestrsize();
uint32_t hash = 0;
MurmurHash3_x86_32( ns, len, 0, &hash);
const char* opType = it->getField( "op" ).valuestrsafe();
if (getGlobalServiceContext()->getGlobalStorageEngine()->supportsDocLocking() &&
isCrudOpType(opType)) {
BSONElement id;
switch (opType[0]) {
case 'u':
id = it->getField("o2").Obj()["_id"];
break;
case 'd':
case 'i':
id = it->getField("o").Obj()["_id"];
break;
}
const size_t idHash = BSONElement::Hasher()( id );
MurmurHash3_x86_32(&idHash, sizeof(idHash), hash, &hash);
}
(*writerVectors)[hash % writerVectors->size()].push_back(*it);
}
}
} // namespace
// Doles out all the work to the writer pool threads and waits for them to complete
// static
OpTime SyncTail::multiApply(OperationContext* txn,
const OpQueue& ops,
threadpool::ThreadPool* prefetcherPool,
threadpool::ThreadPool* writerPool,
MultiSyncApplyFunc func,
SyncTail* sync,
bool supportsWaitingUntilDurable) {
invariant(prefetcherPool);
invariant(writerPool);
invariant(func);
invariant(sync);
if (getGlobalServiceContext()->getGlobalStorageEngine()->isMmapV1()) {
// Use a ThreadPool to prefetch all the operations in a batch.
prefetchOps(ops.getDeque(), prefetcherPool);
}
std::vector< std::vector<BSONObj> > writerVectors(replWriterThreadCount);
fillWriterVectors(ops.getDeque(), &writerVectors);
LOG(2) << "replication batch size is " << ops.getDeque().size() << endl;
// We must grab this because we're going to grab write locks later.
// We hold this mutex the entire time we're writing; it doesn't matter
// because all readers are blocked anyway.
SimpleMutex::scoped_lock fsynclk(filesLockedFsync);
// stop all readers until we're done
Lock::ParallelBatchWriterMode pbwm(txn->lockState());
ReplicationCoordinator* replCoord = getGlobalReplicationCoordinator();
if (replCoord->getMemberState().primary() &&
!replCoord->isWaitingForApplierToDrain()) {
severe() << "attempting to replicate ops while primary";
fassertFailed(28527);
}
applyOps(writerVectors, writerPool, func, sync);
if (inShutdown()) {
return OpTime();
}
const bool mustWaitUntilDurable = replCoord->isV1ElectionProtocol() &&
supportsWaitingUntilDurable;
if (mustWaitUntilDurable) {
txn->recoveryUnit()->goingToWaitUntilDurable();
}
OpTime lastOpTime = writeOpsToOplog(txn, ops.getDeque());
if (mustWaitUntilDurable) {
txn->recoveryUnit()->waitUntilDurable();
}
ReplClientInfo::forClient(txn->getClient()).setLastOp(lastOpTime);
replCoord->setMyLastOptime(lastOpTime);
setNewTimestamp(lastOpTime.getTimestamp());
BackgroundSync::get()->notify(txn);
return lastOpTime;
}
void SyncTail::oplogApplication(OperationContext* txn, const OpTime& endOpTime) {
_applyOplogUntil(txn, endOpTime);
}
/* applies oplog from "now" until endOpTime using the applier threads for initial sync*/
void SyncTail::_applyOplogUntil(OperationContext* txn, const OpTime& endOpTime) {
unsigned long long bytesApplied = 0;
unsigned long long entriesApplied = 0;
while (true) {
OpQueue ops;
while (!tryPopAndWaitForMore(txn, &ops, getGlobalReplicationCoordinator())) {
// nothing came back last time, so go again
if (ops.empty()) continue;
// Check if we reached the end
const BSONObj currentOp = ops.back();
const OpTime currentOpTime = extractOpTime(currentOp);
// When we reach the end return this batch
if (currentOpTime == endOpTime) {
break;
}
else if (currentOpTime > endOpTime) {
severe() << "Applied past expected end " << endOpTime << " to " << currentOpTime
<< " without seeing it. Rollback?";
fassertFailedNoTrace(18693);
}
// apply replication batch limits
if (ops.getSize() > replBatchLimitBytes)
break;
if (ops.getDeque().size() > replBatchLimitOperations)
break;
};
if (ops.empty()) {
severe() << "got no ops for batch...";
fassertFailedNoTrace(18692);
}
const BSONObj lastOp = ops.back().getOwned();
// Tally operation information
bytesApplied += ops.getSize();
entriesApplied += ops.getDeque().size();
const OpTime lastOpTime = multiApply(txn,
ops,
&_prefetcherPool,
&_writerPool,
_applyFunc,
this,
supportsWaitingUntilDurable());
if (inShutdown()) {
return;
}
// if the last op applied was our end, return
if (lastOpTime == endOpTime) {
LOG(1) << "SyncTail applied " << entriesApplied
<< " entries (" << bytesApplied << " bytes)"
<< " and finished at opTime " << endOpTime;
return;
}
} // end of while (true)
}
namespace {
void tryToGoLiveAsASecondary(OperationContext* txn, ReplicationCoordinator* replCoord) {
if (replCoord->isInPrimaryOrSecondaryState()) {
return;
}
ScopedTransaction transaction(txn, MODE_S);
Lock::GlobalRead readLock(txn->lockState());
if (replCoord->getMaintenanceMode()) {
// we're not actually going live
return;
}
// Only state RECOVERING can transition to SECONDARY.
MemberState state(replCoord->getMemberState());
if (!state.recovering()) {
return;
}
OpTime minvalid = getMinValid(txn);
if (minvalid > replCoord->getMyLastOptime()) {
return;
}
bool worked = replCoord->setFollowerMode(MemberState::RS_SECONDARY);
if (!worked) {
warning() << "Failed to transition into " << MemberState(MemberState::RS_SECONDARY)
<< ". Current state: " << replCoord->getMemberState();
}
}
}
/* tail an oplog. ok to return, will be re-called. */
void SyncTail::oplogApplication() {
ReplicationCoordinator* replCoord = getGlobalReplicationCoordinator();
while(!inShutdown()) {
OpQueue ops;
OperationContextImpl txn;
Timer batchTimer;
int lastTimeChecked = 0;
do {
int now = batchTimer.seconds();
// apply replication batch limits
if (!ops.empty()) {
if (now > replBatchLimitSeconds)
break;
if (ops.getDeque().size() > replBatchLimitOperations)
break;
}
// occasionally check some things
// (always checked in the first iteration of this do-while loop, because
// ops is empty)
if (ops.empty() || now > lastTimeChecked) {
BackgroundSync* bgsync = BackgroundSync::get();
if (bgsync->getInitialSyncRequestedFlag()) {
// got a resync command
return;
}
lastTimeChecked = now;
// can we become secondary?
// we have to check this before calling mgr, as we must be a secondary to
// become primary
tryToGoLiveAsASecondary(&txn, replCoord);
}
const int slaveDelaySecs = replCoord->getSlaveDelaySecs().count();
if (!ops.empty() && slaveDelaySecs > 0) {
const BSONObj lastOp = ops.back();
const unsigned int opTimestampSecs = lastOp["ts"].timestamp().getSecs();
// Stop the batch as the lastOp is too new to be applied. If we continue
// on, we can get ops that are way ahead of the delay and this will
// make this thread sleep longer when handleSlaveDelay is called
// and apply ops much sooner than we like.
if (opTimestampSecs > static_cast<unsigned int>(time(0) - slaveDelaySecs)) {
break;
}
}
// keep fetching more ops as long as we haven't filled up a full batch yet
} while (!tryPopAndWaitForMore(&txn, &ops, replCoord) && // tryPopAndWaitForMore returns
// true when we need to end a
// batch early
(ops.getSize() < replBatchLimitBytes) &&
!inShutdown());
// For pausing replication in tests
while (MONGO_FAIL_POINT(rsSyncApplyStop)) {
sleepmillis(0);
}
if (ops.empty()) {
continue;
}
const BSONObj lastOp = ops.back();
handleSlaveDelay(lastOp);
// Set minValid to the last op to be applied in this next batch.
// This will cause this node to go into RECOVERING state
// if we should crash and restart before updating the oplog
setMinValid(&txn, extractOpTime(lastOp));
multiApply(&txn,
ops,
&_prefetcherPool,
&_writerPool,
_applyFunc,
this,
supportsWaitingUntilDurable());
}
}
// Copies ops out of the bgsync queue into the deque passed in as a parameter.
// Returns true if the batch should be ended early.
// Batch should end early if we encounter a command, or if
// there are no further ops in the bgsync queue to read.
// This function also blocks 1 second waiting for new ops to appear in the bgsync
// queue. We can't block forever because there are maintenance things we need
// to periodically check in the loop.
bool SyncTail::tryPopAndWaitForMore(OperationContext* txn,
SyncTail::OpQueue* ops,
ReplicationCoordinator* replCoord) {
BSONObj op;
// Check to see if there are ops waiting in the bgsync queue
bool peek_success = peek(&op);
if (!peek_success) {
// if we don't have anything in the queue, wait a bit for something to appear
if (ops->empty()) {
if (replCoord->isWaitingForApplierToDrain()) {
BackgroundSync::get()->waitUntilPaused();
if (peek(&op)) {
// The producer generated a last batch of ops before pausing so return
// false so that we'll come back and apply them before signaling the drain
// is complete.
return false;
}
replCoord->signalDrainComplete(txn);
}
// block up to 1 second
_networkQueue->waitForMore();
return false;
}
// otherwise, apply what we have
return true;
}
const char* ns = op["ns"].valuestrsafe();
// check for commands
if ((op["op"].valuestrsafe()[0] == 'c') ||
// Index builds are acheived through the use of an insert op, not a command op.
// The following line is the same as what the insert code uses to detect an index build.
( *ns != '\0' && nsToCollectionSubstring(ns) == "system.indexes" )) {
if (ops->empty()) {
// apply commands one-at-a-time
ops->push_back(op);
_networkQueue->consume();
}
// otherwise, apply what we have so far and come back for the command
return true;
}
// check for oplog version change
BSONElement elemVersion = op["v"];
int curVersion = 0;
if (elemVersion.eoo())
// missing version means version 1
curVersion = 1;
else
curVersion = elemVersion.Int();
if (curVersion != OPLOG_VERSION) {
severe() << "expected oplog version " << OPLOG_VERSION << " but found version "
<< curVersion << " in oplog entry: " << op;
fassertFailedNoTrace(18820);
}
// Copy the op to the deque and remove it from the bgsync queue.
ops->push_back(op);
_networkQueue->consume();
// Go back for more ops
return false;
}
void SyncTail::handleSlaveDelay(const BSONObj& lastOp) {
ReplicationCoordinator* replCoord = getGlobalReplicationCoordinator();
int slaveDelaySecs = replCoord->getSlaveDelaySecs().count();
// ignore slaveDelay if the box is still initializing. once
// it becomes secondary we can worry about it.
if( slaveDelaySecs > 0 && replCoord->getMemberState().secondary() ) {
const Timestamp ts = lastOp["ts"].timestamp();
long long a = ts.getSecs();
long long b = time(0);
long long lag = b - a;
long long sleeptime = slaveDelaySecs - lag;
if( sleeptime > 0 ) {
uassert(12000, "rs slaveDelay differential too big check clocks and systems",
sleeptime < 0x40000000);
if( sleeptime < 60 ) {
sleepsecs((int) sleeptime);
}
else {
warning() << "slavedelay causing a long sleep of " << sleeptime
<< " seconds";
// sleep(hours) would prevent reconfigs from taking effect & such!
long long waitUntil = b + sleeptime;
while(time(0) < waitUntil) {
sleepsecs(6);
// Handle reconfigs that changed the slave delay
if (replCoord->getSlaveDelaySecs().count() != slaveDelaySecs)
break;
}
}
}
} // endif slaveDelay
}
void SyncTail::setHostname(const std::string& hostname) {
_hostname = hostname;
}
BSONObj SyncTail::getMissingDoc(OperationContext* txn, Database* db, const BSONObj& o) {
OplogReader missingObjReader; // why are we using OplogReader to run a non-oplog query?
const char *ns = o.getStringField("ns");
// capped collections
Collection* collection = db->getCollection(ns);
if ( collection && collection->isCapped() ) {
log() << "missing doc, but this is okay for a capped collection (" << ns << ")";
return BSONObj();
}
const int retryMax = 3;
for (int retryCount = 1; retryCount <= retryMax; ++retryCount) {
if (retryCount != 1) {
// if we are retrying, sleep a bit to let the network possibly recover
sleepsecs(retryCount * retryCount);
}
try {
bool ok = missingObjReader.connect(HostAndPort(_hostname));
if (!ok) {
warning() << "network problem detected while connecting to the "
<< "sync source, attempt " << retryCount << " of "
<< retryMax << endl;
continue; // try again
}
}
catch (const SocketException&) {
warning() << "network problem detected while connecting to the "
<< "sync source, attempt " << retryCount << " of "
<< retryMax << endl;
continue; // try again
}
// might be more than just _id in the update criteria
BSONObj query = BSONObjBuilder().append(o.getObjectField("o2")["_id"]).obj();
BSONObj missingObj;
try {
missingObj = missingObjReader.findOne(ns, query);
}
catch (const SocketException&) {
warning() << "network problem detected while fetching a missing document from the "
<< "sync source, attempt " << retryCount << " of "
<< retryMax << endl;
continue; // try again
}
catch (DBException& e) {
error() << "assertion fetching missing object: " << e.what() << endl;
throw;
}
// success!
return missingObj;
}
// retry count exceeded
msgasserted(15916, str::stream() <<
"Can no longer connect to initial sync source: " << _hostname);
}
bool SyncTail::shouldRetry(OperationContext* txn, const BSONObj& o) {
const NamespaceString nss(o.getStringField("ns"));
MONGO_WRITE_CONFLICT_RETRY_LOOP_BEGIN {
// Take an X lock on the database in order to preclude other modifications.
// Also, the database might not exist yet, so create it.
AutoGetOrCreateDb autoDb(txn, nss.db(), MODE_X);
Database* const db = autoDb.getDb();
// we don't have the object yet, which is possible on initial sync. get it.
log() << "adding missing object" << endl; // rare enough we can log
BSONObj missingObj = getMissingDoc(txn, db, o);
if( missingObj.isEmpty() ) {
log() << "missing object not found on source."
" presumably deleted later in oplog";
log() << "o2: " << o.getObjectField("o2").toString();
log() << "o firstfield: " << o.getObjectField("o").firstElementFieldName();
return false;
}
else {
WriteUnitOfWork wunit(txn);
Collection* const coll = db->getOrCreateCollection(txn, nss.toString());
invariant(coll);
StatusWith<RecordId> result = coll->insertDocument(txn, missingObj, true);
uassert(15917,
str::stream() << "failed to insert missing doc: "
<< result.getStatus().toString(),
result.isOK() );
LOG(1) << "inserted missing doc: " << missingObj.toString() << endl;
wunit.commit();
return true;
}
} MONGO_WRITE_CONFLICT_RETRY_LOOP_END(txn, "InsertRetry", nss.ns());
// fixes compile errors on GCC - see SERVER-18219 for details
MONGO_UNREACHABLE;
}
static AtomicUInt32 replWriterWorkerId;
static void initializeWriterThread() {
// Only do this once per thread
if (!ClientBasic::getCurrent()) {
Client::initThreadIfNotAlready();
AuthorizationSession::get(cc())->grantInternalAuthorization();
}
}
// This free function is used by the writer threads to apply each op
void multiSyncApply(const std::vector<BSONObj>& ops, SyncTail* st) {
initializeWriterThread();
OperationContextImpl txn;
txn.setReplicatedWrites(false);
DisableDocumentValidation validationDisabler(&txn);
// allow us to get through the magic barrier
txn.lockState()->setIsBatchWriter(true);
bool convertUpdatesToUpserts = true;
for (std::vector<BSONObj>::const_iterator it = ops.begin();
it != ops.end();
++it) {
try {
if (!SyncTail::syncApply(&txn, *it, convertUpdatesToUpserts).isOK()) {
fassertFailedNoTrace(16359);
}
}
catch (const DBException& e) {
error() << "writer worker caught exception: " << causedBy(e)
<< " on: " << it->toString();
if (inShutdown()) {
return;
}
fassertFailedNoTrace(16360);
}
}
}
// This free function is used by the initial sync writer threads to apply each op
void multiInitialSyncApply(const std::vector<BSONObj>& ops, SyncTail* st) {
initializeWriterThread();
OperationContextImpl txn;
txn.setReplicatedWrites(false);
DisableDocumentValidation validationDisabler(&txn);
// allow us to get through the magic barrier
txn.lockState()->setIsBatchWriter(true);
bool convertUpdatesToUpserts = false;
for (std::vector<BSONObj>::const_iterator it = ops.begin();
it != ops.end();
++it) {
try {
if (!SyncTail::syncApply(&txn, *it, convertUpdatesToUpserts).isOK()) {
if (st->shouldRetry(&txn, *it)) {
if (!SyncTail::syncApply(&txn, *it, convertUpdatesToUpserts).isOK()) {
fassertFailedNoTrace(15915);
}
}
// If shouldRetry() returns false, fall through.
// This can happen if the document that was moved and missed by Cloner
// subsequently got deleted and no longer exists on the Sync Target at all
}
}
catch (const DBException& e) {
error() << "writer worker caught exception: " << causedBy(e)
<< " on: " << it->toString();
if (inShutdown()) {
return;
}
fassertFailedNoTrace(16361);
}
}
}
} // namespace repl
} // namespace mongo
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