int Balancer::_moveChunks( const vector<CandidateChunkPtr>* candidateChunks , bool secondaryThrottle ) {
int movedCount = 0;
for ( vector<CandidateChunkPtr>::const_iterator it = candidateChunks->begin(); it != candidateChunks->end(); ++it ) {
const CandidateChunk& chunkInfo = *it->get();
DBConfigPtr cfg = grid.getDBConfig( chunkInfo.ns );
verify( cfg );
ChunkManagerPtr cm = cfg->getChunkManager( chunkInfo.ns );
verify( cm );
ChunkPtr c = cm->findChunk( chunkInfo.chunk.min );
if ( c->getMin().woCompare( chunkInfo.chunk.min ) || c->getMax().woCompare( chunkInfo.chunk.max ) ) {
// likely a split happened somewhere
cm = cfg->getChunkManager( chunkInfo.ns , true /* reload */);
verify( cm );
c = cm->findChunk( chunkInfo.chunk.min );
if ( c->getMin().woCompare( chunkInfo.chunk.min ) || c->getMax().woCompare( chunkInfo.chunk.max ) ) {
log() << "chunk mismatch after reload, ignoring will retry issue " << chunkInfo.chunk.toString() << endl;
continue;
}
}
BSONObj res;
if ( c->moveAndCommit( Shard::make( chunkInfo.to ) , Chunk::MaxChunkSize , secondaryThrottle , res ) ) {
movedCount++;
continue;
}
// the move requires acquiring the collection metadata's lock, which can fail
log() << "balancer move failed: " << res << " from: " << chunkInfo.from << " to: " << chunkInfo.to
<< " chunk: " << chunkInfo.chunk << endl;
if ( res["chunkTooBig"].trueValue() ) {
// reload just to be safe
cm = cfg->getChunkManager( chunkInfo.ns );
verify( cm );
c = cm->findChunk( chunkInfo.chunk.min );
log() << "forcing a split because migrate failed for size reasons" << endl;
res = BSONObj();
c->singleSplit( true , res );
log() << "forced split results: " << res << endl;
if ( ! res["ok"].trueValue() ) {
log() << "marking chunk as jumbo: " << c->toString() << endl;
c->markAsJumbo();
// we increment moveCount so we do another round right away
movedCount++;
}
}
}
return movedCount;
}
bool run(const string& , BSONObj& cmdObj, string& errmsg, BSONObjBuilder& result, bool) {
ShardConnection::sync();
string ns = cmdObj.firstElement().valuestrsafe();
if ( ns.size() == 0 ) {
errmsg = "no ns";
return false;
}
DBConfigPtr config = grid.getDBConfig( ns );
if ( ! config->isSharded( ns ) ) {
errmsg = "ns not sharded. have to shard before can split";
return false;
}
BSONObj find = cmdObj.getObjectField( "find" );
if ( find.isEmpty() ) {
find = cmdObj.getObjectField( "middle" );
if ( find.isEmpty() ) {
errmsg = "need to specify find or middle";
return false;
}
}
ChunkManagerPtr info = config->getChunkManager( ns );
ChunkPtr chunk = info->findChunk( find );
BSONObj middle = cmdObj.getObjectField( "middle" );
assert( chunk.get() );
log() << "splitting: " << ns << " shard: " << chunk << endl;
BSONObj res;
ChunkPtr p;
if ( middle.isEmpty() ) {
p = chunk->singleSplit( true /* force a split even if not enough data */ , res );
}
else {
// sanity check if the key provided is a valid split point
if ( ( middle == chunk->getMin() ) || ( middle == chunk->getMax() ) ) {
errmsg = "cannot split on initial or final chunk's key";
return false;
}
vector<BSONObj> splitPoints;
splitPoints.push_back( middle );
p = chunk->multiSplit( splitPoints , res );
}
if ( p.get() == NULL ) {
errmsg = "split failed";
result.append( "cause" , res );
return false;
}
return true;
}
int Balancer::_moveChunks( const vector<CandidateChunkPtr>* candidateChunks ) {
int movedCount = 0;
for ( vector<CandidateChunkPtr>::const_iterator it = candidateChunks->begin(); it != candidateChunks->end(); ++it ) {
const CandidateChunk& chunkInfo = *it->get();
DBConfigPtr cfg = grid.getDBConfig( chunkInfo.ns );
assert( cfg );
ChunkManagerPtr cm = cfg->getChunkManager( chunkInfo.ns );
assert( cm );
const BSONObj& chunkToMove = chunkInfo.chunk;
ChunkPtr c = cm->findChunk( chunkToMove["min"].Obj() );
if ( c->getMin().woCompare( chunkToMove["min"].Obj() ) || c->getMax().woCompare( chunkToMove["max"].Obj() ) ) {
// likely a split happened somewhere
cm = cfg->getChunkManager( chunkInfo.ns , true /* reload */);
assert( cm );
c = cm->findChunk( chunkToMove["min"].Obj() );
if ( c->getMin().woCompare( chunkToMove["min"].Obj() ) || c->getMax().woCompare( chunkToMove["max"].Obj() ) ) {
log() << "chunk mismatch after reload, ignoring will retry issue cm: "
<< c->getMin() << " min: " << chunkToMove["min"].Obj() << endl;
continue;
}
}
BSONObj res;
if ( c->moveAndCommit( Shard::make( chunkInfo.to ) , Chunk::MaxChunkSize , res ) ) {
movedCount++;
continue;
}
// the move requires acquiring the collection metadata's lock, which can fail
log() << "balacer move failed: " << res << " from: " << chunkInfo.from << " to: " << chunkInfo.to
<< " chunk: " << chunkToMove << endl;
if ( res["chunkTooBig"].trueValue() ) {
// reload just to be safe
cm = cfg->getChunkManager( chunkInfo.ns );
assert( cm );
c = cm->findChunk( chunkToMove["min"].Obj() );
log() << "forcing a split because migrate failed for size reasons" << endl;
res = BSONObj();
c->singleSplit( true , res );
log() << "forced split results: " << res << endl;
// TODO: if the split fails, mark as jumbo SERVER-2571
}
}
return movedCount;
}
int Balancer::_moveChunks(const vector<CandidateChunkPtr>* candidateChunks,
bool secondaryThrottle,
bool waitForDelete)
{
int movedCount = 0;
for ( vector<CandidateChunkPtr>::const_iterator it = candidateChunks->begin(); it != candidateChunks->end(); ++it ) {
const CandidateChunk& chunkInfo = *it->get();
// Changes to metadata, borked metadata, and connectivity problems should cause us to
// abort this chunk move, but shouldn't cause us to abort the entire round of chunks.
// TODO: Handle all these things more cleanly, since they're expected problems
try {
DBConfigPtr cfg = grid.getDBConfig( chunkInfo.ns );
verify( cfg );
// NOTE: We purposely do not reload metadata here, since _doBalanceRound already
// tried to do so once.
ChunkManagerPtr cm = cfg->getChunkManager( chunkInfo.ns );
verify( cm );
ChunkPtr c = cm->findIntersectingChunk( chunkInfo.chunk.min );
if ( c->getMin().woCompare( chunkInfo.chunk.min ) || c->getMax().woCompare( chunkInfo.chunk.max ) ) {
// likely a split happened somewhere
cm = cfg->getChunkManager( chunkInfo.ns , true /* reload */);
verify( cm );
c = cm->findIntersectingChunk( chunkInfo.chunk.min );
if ( c->getMin().woCompare( chunkInfo.chunk.min ) || c->getMax().woCompare( chunkInfo.chunk.max ) ) {
log() << "chunk mismatch after reload, ignoring will retry issue " << chunkInfo.chunk.toString() << endl;
continue;
}
}
BSONObj res;
if (c->moveAndCommit(Shard::make(chunkInfo.to),
Chunk::MaxChunkSize,
secondaryThrottle,
waitForDelete,
0, /* maxTimeMS */
res)) {
movedCount++;
continue;
}
// the move requires acquiring the collection metadata's lock, which can fail
log() << "balancer move failed: " << res << " from: " << chunkInfo.from << " to: " << chunkInfo.to
<< " chunk: " << chunkInfo.chunk << endl;
if ( res["chunkTooBig"].trueValue() ) {
// reload just to be safe
cm = cfg->getChunkManager( chunkInfo.ns );
verify( cm );
c = cm->findIntersectingChunk( chunkInfo.chunk.min );
log() << "forcing a split because migrate failed for size reasons" << endl;
res = BSONObj();
c->singleSplit( true , res );
log() << "forced split results: " << res << endl;
if ( ! res["ok"].trueValue() ) {
log() << "marking chunk as jumbo: " << c->toString() << endl;
c->markAsJumbo();
// we increment moveCount so we do another round right away
movedCount++;
}
}
}
catch( const DBException& ex ) {
warning() << "could not move chunk " << chunkInfo.chunk.toString()
<< ", continuing balancing round" << causedBy( ex ) << endl;
}
}
return movedCount;
}
