int run() {
Client::initThread( "oplogreplay" );
toolInfoLog() << "going to connect" << std::endl;
OplogReader r;
r.setTailingQueryOptions( QueryOption_SlaveOk | QueryOption_AwaitData );
r.connect(mongoOplogGlobalParams.from);
toolInfoLog() << "connected" << std::endl;
OpTime start(time(0) - mongoOplogGlobalParams.seconds, 0);
toolInfoLog() << "starting from " << start.toStringPretty() << std::endl;
r.tailingQueryGTE(mongoOplogGlobalParams.ns.c_str(), start);
int num = 0;
while ( r.more() ) {
BSONObj o = r.next();
if (logger::globalLogDomain()->shouldLog(logger::LogSeverity::Debug(2))) {
toolInfoLog() << o << std::endl;
}
if ( o["$err"].type() ) {
toolError() << "error getting oplog" << std::endl;
toolError() << o << std::endl;
return -1;
}
bool print = ++num % 100000 == 0;
if (print) {
toolInfoLog() << num << "\t" << o << std::endl;
}
if ( o["op"].String() == "n" )
continue;
BSONObjBuilder b( o.objsize() + 32 );
BSONArrayBuilder updates( b.subarrayStart( "applyOps" ) );
updates.append( o );
updates.done();
BSONObj c = b.obj();
BSONObj res;
bool ok = conn().runCommand( "admin" , c , res );
if (!ok) {
toolError() << res << std::endl;
} else if (print) {
toolInfoLog() << res << std::endl;
}
}
return 0;
}
void BackgroundSync::produce() {
// this oplog reader does not do a handshake because we don't want the server it's syncing
// from to track how far it has synced
OplogReader r;
OpTime lastOpTimeFetched;
// find a target to sync from the last op time written
getOplogReader(r);
// no server found
{
boost::unique_lock<boost::mutex> lock(_mutex);
if (_currentSyncTarget == NULL) {
lock.unlock();
sleepsecs(1);
// if there is no one to sync from
return;
}
lastOpTimeFetched = _lastOpTimeFetched;
}
r.tailingQueryGTE(rsoplog, lastOpTimeFetched);
// if target cut connections between connecting and querying (for
// example, because it stepped down) we might not have a cursor
if (!r.haveCursor()) {
return;
}
uassert(1000, "replSet source for syncing doesn't seem to be await capable -- is it an older version of mongodb?", r.awaitCapable() );
if (isRollbackRequired(r)) {
stop();
return;
}
while (!inShutdown()) {
if (!r.moreInCurrentBatch()) {
// Check some things periodically
// (whenever we run out of items in the
// current cursor batch)
int bs = r.currentBatchMessageSize();
if( bs > 0 && bs < BatchIsSmallish ) {
// on a very low latency network, if we don't wait a little, we'll be
// getting ops to write almost one at a time. this will both be expensive
// for the upstream server as well as potentially defeating our parallel
// application of batches on the secondary.
//
// the inference here is basically if the batch is really small, we are
// "caught up".
//
dassert( !Lock::isLocked() );
sleepmillis(SleepToAllowBatchingMillis);
}
if (theReplSet->gotForceSync()) {
return;
}
// If we are transitioning to primary state, we need to leave
// this loop in order to go into bgsync-pause mode.
if (isAssumingPrimary() || theReplSet->isPrimary()) {
return;
}
// re-evaluate quality of sync target
if (shouldChangeSyncTarget()) {
return;
}
{
//record time for each getmore
TimerHolder batchTimer(&getmoreReplStats);
// This calls receiveMore() on the oplogreader cursor.
// It can wait up to five seconds for more data.
r.more();
}
networkByteStats.increment(r.currentBatchMessageSize());
if (!r.moreInCurrentBatch()) {
// If there is still no data from upstream, check a few more things
// and then loop back for another pass at getting more data
{
boost::unique_lock<boost::mutex> lock(_mutex);
if (_pause ||
!_currentSyncTarget ||
!_currentSyncTarget->hbinfo().hbstate.readable()) {
return;
}
}
r.tailCheck();
if( !r.haveCursor() ) {
LOG(1) << "replSet end syncTail pass" << rsLog;
return;
}
continue;
}
}
// At this point, we are guaranteed to have at least one thing to read out
// of the oplogreader cursor.
BSONObj o = r.nextSafe().getOwned();
opsReadStats.increment();
{
boost::unique_lock<boost::mutex> lock(_mutex);
_appliedBuffer = false;
}
OCCASIONALLY {
LOG(2) << "bgsync buffer has " << _buffer.size() << " bytes" << rsLog;
}
// the blocking queue will wait (forever) until there's room for us to push
_buffer.push(o);
bufferCountGauge.increment();
bufferSizeGauge.increment(getSize(o));
{
boost::unique_lock<boost::mutex> lock(_mutex);
_lastH = o["h"].numberLong();
_lastOpTimeFetched = o["ts"]._opTime();
LOG(3) << "replSet lastOpTimeFetched: "
<< _lastOpTimeFetched.toStringPretty() << rsLog;
}
}
}
bool ReplSetImpl::_initialSyncOplogApplication(OplogReader& r, const Member *source,
const OpTime& applyGTE, const OpTime& minValid) {
const string hn = source->fullName();
OplogReader missingObjReader;
try {
r.tailingQueryGTE( rsoplog, applyGTE );
if ( !r.haveCursor() ) {
log() << "replSet initial sync oplog query error" << rsLog;
return false;
}
{
if( !r.more() ) {
sethbmsg("replSet initial sync error reading remote oplog");
log() << "replSet initial sync error remote oplog (" << rsoplog << ") on host " << hn << " is empty?" << rsLog;
return false;
}
bo op = r.next();
OpTime t = op["ts"]._opTime();
r.putBack(op);
if( op.firstElementFieldName() == string("$err") ) {
log() << "replSet initial sync error querying " << rsoplog << " on " << hn << " : " << op.toString() << rsLog;
return false;
}
uassert( 13508 , str::stream() << "no 'ts' in first op in oplog: " << op , !t.isNull() );
if( t > applyGTE ) {
sethbmsg(str::stream() << "error " << hn << " oplog wrapped during initial sync");
log() << "replSet initial sync expected first optime of " << applyGTE << rsLog;
log() << "replSet initial sync but received a first optime of " << t << " from " << hn << rsLog;
return false;
}
sethbmsg(str::stream() << "initial oplog application from " << hn << " starting at "
<< t.toStringPretty() << " to " << minValid.toStringPretty());
}
}
catch(DBException& e) {
log() << "replSet initial sync failing: " << e.toString() << rsLog;
return false;
}
/* we lock outside the loop to avoid the overhead of locking on every operation. */
writelock lk("");
// todo : use exhaust
OpTime ts;
time_t start = time(0);
unsigned long long n = 0;
while( 1 ) {
try {
if( !r.more() )
break;
BSONObj o = r.nextSafe(); /* note we might get "not master" at some point */
ts = o["ts"]._opTime();
{
if( (source->state() != MemberState::RS_PRIMARY &&
source->state() != MemberState::RS_SECONDARY) ||
replSetForceInitialSyncFailure ) {
int f = replSetForceInitialSyncFailure;
if( f > 0 ) {
replSetForceInitialSyncFailure = f-1;
log() << "replSet test code invoked, replSetForceInitialSyncFailure" << rsLog;
throw DBException("forced error",0);
}
log() << "replSet we are now primary" << rsLog;
throw DBException("primary changed",0);
}
if( ts >= applyGTE ) { // optimes before we started copying need not be applied.
bool failedUpdate = syncApply(o);
if( failedUpdate ) {
// we don't have the object yet, which is possible on initial sync. get it.
log() << "replSet info adding missing object" << endl; // rare enough we can log
if( !missingObjReader.connect(hn) ) { // ok to call more than once
log() << "replSet initial sync fails, couldn't connect to " << hn << endl;
return false;
}
const char *ns = o.getStringField("ns");
BSONObj query = BSONObjBuilder().append(o.getObjectField("o2")["_id"]).obj(); // might be more than just _id in the update criteria
BSONObj missingObj;
try {
missingObj = missingObjReader.findOne(
ns,
query );
} catch(...) {
log() << "replSet assertion fetching missing object" << endl;
throw;
}
if( missingObj.isEmpty() ) {
log() << "replSet missing object not found on source. presumably deleted later in oplog" << endl;
log() << "replSet o2: " << o.getObjectField("o2").toString() << endl;
log() << "replSet o firstfield: " << o.getObjectField("o").firstElementFieldName() << endl;
}
else {
Client::Context ctx(ns);
try {
DiskLoc d = theDataFileMgr.insert(ns, (void*) missingObj.objdata(), missingObj.objsize());
assert( !d.isNull() );
} catch(...) {
log() << "replSet assertion during insert of missing object" << endl;
throw;
}
// now reapply the update from above
bool failed = syncApply(o);
if( failed ) {
log() << "replSet update still fails after adding missing object " << ns << endl;
assert(false);
}
}
}
}
_logOpObjRS(o); /* with repl sets we write the ops to our oplog too */
}
if ( ++n % 1000 == 0 ) {
time_t now = time(0);
if (now - start > 10) {
// simple progress metering
log() << "replSet initialSyncOplogApplication applied " << n << " operations, synced to "
<< ts.toStringPretty() << rsLog;
start = now;
}
}
if ( ts > minValid ) {
break;
}
getDur().commitIfNeeded();
}
catch (DBException& e) {
// skip duplicate key exceptions
if( e.getCode() == 11000 || e.getCode() == 11001 ) {
continue;
}
// handle cursor not found (just requery)
if( e.getCode() == 13127 ) {
log() << "replSet requerying oplog after cursor not found condition, ts: " << ts.toStringPretty() << endl;
r.resetCursor();
r.tailingQueryGTE(rsoplog, ts);
if( r.haveCursor() ) {
continue;
}
}
// TODO: handle server restart
if( ts <= minValid ) {
// didn't make it far enough
log() << "replSet initial sync failing, error applying oplog : " << e.toString() << rsLog;
return false;
}
// otherwise, whatever
break;
}
}
return true;
}
bool replset::InitialSync::oplogApplication(OplogReader& r, const Member* source,
const OpTime& applyGTE, const OpTime& minValid) {
const string hn = source->fullName();
try {
r.tailingQueryGTE( rsoplog, applyGTE );
if ( !r.haveCursor() ) {
log() << "replSet initial sync oplog query error" << rsLog;
return false;
}
{
if( !r.more() ) {
sethbmsg("replSet initial sync error reading remote oplog");
log() << "replSet initial sync error remote oplog (" << rsoplog << ") on host " << hn << " is empty?" << rsLog;
return false;
}
bo op = r.next();
OpTime t = op["ts"]._opTime();
r.putBack(op);
if( op.firstElementFieldName() == string("$err") ) {
log() << "replSet initial sync error querying " << rsoplog << " on " << hn << " : " << op.toString() << rsLog;
return false;
}
uassert( 13508 , str::stream() << "no 'ts' in first op in oplog: " << op , !t.isNull() );
if( t > applyGTE ) {
sethbmsg(str::stream() << "error " << hn << " oplog wrapped during initial sync");
log() << "replSet initial sync expected first optime of " << applyGTE << rsLog;
log() << "replSet initial sync but received a first optime of " << t << " from " << hn << rsLog;
return false;
}
sethbmsg(str::stream() << "initial oplog application from " << hn << " starting at "
<< t.toStringPretty() << " to " << minValid.toStringPretty());
}
}
catch(DBException& e) {
log() << "replSet initial sync failing: " << e.toString() << rsLog;
return false;
}
/* we lock outside the loop to avoid the overhead of locking on every operation. */
writelock lk("");
// todo : use exhaust
OpTime ts;
time_t start = time(0);
unsigned long long n = 0;
int fails = 0;
while( ts < minValid ) {
try {
// There are some special cases with initial sync (see the catch block), so we
// don't want to break out of this while until we've reached minvalid. Thus, we'll
// keep trying to requery.
if( !r.more() ) {
OCCASIONALLY log() << "replSet initial sync oplog: no more records" << endl;
sleepsecs(1);
r.resetCursor();
r.tailingQueryGTE(rsoplog, theReplSet->lastOpTimeWritten);
if ( !r.haveCursor() ) {
if (fails++ > 30) {
log() << "replSet initial sync tried to query oplog 30 times, giving up" << endl;
return false;
}
}
continue;
}
BSONObj o = r.nextSafe(); /* note we might get "not master" at some point */
ts = o["ts"]._opTime();
{
if( (source->state() != MemberState::RS_PRIMARY &&
source->state() != MemberState::RS_SECONDARY) ||
replSetForceInitialSyncFailure ) {
int f = replSetForceInitialSyncFailure;
if( f > 0 ) {
replSetForceInitialSyncFailure = f-1;
log() << "replSet test code invoked, replSetForceInitialSyncFailure" << rsLog;
throw DBException("forced error",0);
}
log() << "replSet we are now primary" << rsLog;
throw DBException("primary changed",0);
}
applyOp(o, applyGTE);
}
if ( ++n % 1000 == 0 ) {
time_t now = time(0);
if (now - start > 10) {
// simple progress metering
log() << "replSet initialSyncOplogApplication applied " << n << " operations, synced to "
<< ts.toStringPretty() << rsLog;
start = now;
}
}
getDur().commitIfNeeded();
}
catch (DBException& e) {
// Skip duplicate key exceptions.
// These are relatively common on initial sync: if a document is inserted
// early in the clone step, the insert will be replayed but the document
// will probably already have been cloned over.
if( e.getCode() == 11000 || e.getCode() == 11001 || e.getCode() == 12582) {
continue;
}
// handle cursor not found (just requery)
if( e.getCode() == 13127 ) {
log() << "replSet requerying oplog after cursor not found condition, ts: " << ts.toStringPretty() << endl;
r.resetCursor();
r.tailingQueryGTE(rsoplog, ts);
if( r.haveCursor() ) {
continue;
}
}
// TODO: handle server restart
if( ts <= minValid ) {
// didn't make it far enough
log() << "replSet initial sync failing, error applying oplog : " << e.toString() << rsLog;
return false;
}
// otherwise, whatever, we'll break out of the loop and catch
// anything that's really wrong in syncTail
}
}
return true;
}
