diff options
| -rw-r--r-- | src/mongo/s/d_migrate.cpp | 33 |
1 files changed, 32 insertions, 1 deletions
diff --git a/src/mongo/s/d_migrate.cpp b/src/mongo/s/d_migrate.cpp index a391cbcb8cb..7a784746a58 100644 --- a/src/mongo/s/d_migrate.cpp +++ b/src/mongo/s/d_migrate.cpp @@ -611,6 +611,11 @@ namespace mongo { _cloneLocs.erase( dl ); } + std::size_t cloneLocsRemaining() { + scoped_spinlock lk( _trackerLocks ); + return _cloneLocs.size(); + } + long long mbUsed() const { return _memoryUsed / ( 1024 * 1024 ); } bool getInCriticalSection() const { scoped_lock l(_m); return _inCriticalSection; } @@ -1054,13 +1059,19 @@ namespace mongo { timing.done( 3 ); // 4. + + // Track last result from TO shard for sanity check + BSONObj res; for ( int i=0; i<86400; i++ ) { // don't want a single chunk move to take more than a day verify( !Lock::isLocked() ); + sleepsecs( 1 ); + scoped_ptr<ScopedDbConnection> conn( ScopedDbConnection::getScopedDbConnection( toShard.getConnString() ) ); - BSONObj res; + bool ok; + res = BSONObj(); try { ok = conn->get()->runCommand( "admin" , BSON( "_recvChunkStatus" << 1 ) , res ); res = res.getOwned(); @@ -1106,6 +1117,26 @@ namespace mongo { timing.done(4); // 5. + + // Before we get into the critical section of the migration, let's double check + // that the docs have been cloned + log() << "About to check if it is safe to enter critical section" << endl; + + // Ensure all cloned docs have actually been transferred + std::size_t locsRemaining = migrateFromStatus.cloneLocsRemaining(); + if ( locsRemaining != 0 ) { + + errmsg = + str::stream() << "moveChunk cannot enter critical section before all data is" + << " cloned, " << locsRemaining << " locs were not transferred" + << " but to-shard reported " << res; + + // Should never happen, but safe to abort before critical section + error() << errmsg << migrateLog; + dassert( false ); + return false; + } + { // 5.a // we're under the collection lock here, so no other migrate can change maxVersion or ShardChunkManager state |