Ejemplo n.º 1
0
    void Balancer::_doBalanceRound( DBClientBase& conn, vector<CandidateChunkPtr>* candidateChunks ) {
        verify( candidateChunks );

        //
        // 1. Check whether there is any sharded collection to be balanced by querying
        // the ShardsNS::collections collection
        //

        auto_ptr<DBClientCursor> cursor = conn.query( ShardNS::collection , BSONObj() );
        vector< string > collections;
        while ( cursor->more() ) {
            BSONObj col = cursor->nextSafe();

            // sharded collections will have a shard "key".
            if ( ! col["key"].eoo() && ! col["noBalance"].trueValue() ){
                collections.push_back( col["_id"].String() );
            }
            else if( col["noBalance"].trueValue() ){
                LOG(1) << "not balancing collection " << col["_id"].String() << ", explicitly disabled" << endl;
            }

        }
        cursor.reset();

        if ( collections.empty() ) {
            LOG(1) << "no collections to balance" << endl;
            return;
        }

        //
        // 2. Get a list of all the shards that are participating in this balance round
        // along with any maximum allowed quotas and current utilization. We get the
        // latter by issuing db.serverStatus() (mem.mapped) to all shards.
        //
        // TODO: skip unresponsive shards and mark information as stale.
        //

        vector<Shard> allShards;
        Shard::getAllShards( allShards );
        if ( allShards.size() < 2) {
            LOG(1) << "can't balance without more active shards" << endl;
            return;
        }
        
        ShardInfoMap shardInfo;
        for ( vector<Shard>::const_iterator it = allShards.begin(); it != allShards.end(); ++it ) {
            const Shard& s = *it;
            ShardStatus status = s.getStatus();
            shardInfo[ s.getName() ] = ShardInfo( s.getMaxSize(),
                                                  status.mapped(),
                                                  s.isDraining(),
                                                  status.hasOpsQueued(),
                                                  s.tags()
                                                  );
        }

        //
        // 3. For each collection, check if the balancing policy recommends moving anything around.
        //

        for (vector<string>::const_iterator it = collections.begin(); it != collections.end(); ++it ) {
            const string& ns = *it;

            map< string,vector<BSONObj> > shardToChunksMap;
            cursor = conn.query( ShardNS::chunk , QUERY( "ns" << ns ).sort( "min" ) );
            while ( cursor->more() ) {
                BSONObj chunk = cursor->nextSafe();
                if ( chunk["jumbo"].trueValue() )
                    continue;
                vector<BSONObj>& chunks = shardToChunksMap[chunk["shard"].String()];
                chunks.push_back( chunk.getOwned() );
            }
            cursor.reset();

            if (shardToChunksMap.empty()) {
                LOG(1) << "skipping empty collection (" << ns << ")";
                continue;
            }
            
            for ( vector<Shard>::iterator i=allShards.begin(); i!=allShards.end(); ++i ) {
                // this just makes sure there is an entry in shardToChunksMap for every shard
                Shard s = *i;
                shardToChunksMap[s.getName()].size();
            }

            DistributionStatus status( shardInfo, shardToChunksMap );
            
            // load tags
            conn.ensureIndex( ShardNS::tags, BSON( "ns" << 1 << "min" << 1 ), true );
            cursor = conn.query( ShardNS::tags , QUERY( "ns" << ns ).sort( "min" ) );
            while ( cursor->more() ) {
                BSONObj tag = cursor->nextSafe();
                uassert( 16356 , str::stream() << "tag ranges not valid for: " << ns ,
                         status.addTagRange( TagRange( tag["min"].Obj().getOwned(), 
                                                       tag["max"].Obj().getOwned(), 
                                                       tag["tag"].String() ) ) );
                    
            }
            cursor.reset();
            
            CandidateChunk* p = _policy->balance( ns, status, _balancedLastTime );
            if ( p ) candidateChunks->push_back( CandidateChunkPtr( p ) );
        }
    }
Ejemplo n.º 2
0
    void Balancer::_doBalanceRound( DBClientBase& conn, vector<CandidateChunkPtr>* candidateChunks ){
        assert( candidateChunks );

        //
        // 1. Check whether there is any sharded collection to be balanced by querying
        // the ShardsNS::database collection
        //
        // { "_id" : "test", "partitioned" : true, "primary" : "shard0",
        //   "sharded" : {
        //       "test.images" : { "key" : { "_id" : 1 }, "unique" : false },
        //       ...  
        //   }
        // }
        //

        auto_ptr<DBClientCursor> cursor = conn.query( ShardNS::database , BSON( "partitioned" << true ) );
        vector< string > collections;
        while ( cursor->more() ){
            BSONObj db = cursor->next();

            // A database may be partitioned but not yet have a sharded collection. 
            // 'cursor' will point to docs that do not contain the "sharded" key. Since 
            // there'd be nothing to balance, we want to skip those here.

            BSONElement shardedColls = db["sharded"];
            if ( shardedColls.eoo() ){
                log(2) << "balancer: skipping database with no sharded collection (" 
                      << db["_id"].str() << ")" << endl;
                continue;
            }
            
            BSONObjIterator i( shardedColls.Obj() );
            while ( i.more() ){
                BSONElement e = i.next();
                collections.push_back( e.fieldName() );
            }
        }
        cursor.reset();

        if ( collections.empty() ) {
            log(1) << "balancer: no collections to balance" << endl;
            return;
        }

        //
        // 2. Get a list of all the shards that are participating in this balance round
        // along with any maximum allowed quotas and current utilization. We get the
        // latter by issuing db.serverStatus() (mem.mapped) to all shards.
        //
        // TODO: skip unresponsive shards and mark information as stale.
        //
 
        vector<Shard> allShards;
        Shard::getAllShards( allShards );
        if ( allShards.size() < 2) {
            log(1) << "balancer: can't balance without more active shards" << endl;
            return;
        }

        map< string, BSONObj > shardLimitsMap; 
        for ( vector<Shard>::const_iterator it = allShards.begin(); it != allShards.end(); ++it ){
            const Shard& s = *it;
            ShardStatus status = s.getStatus();

            BSONObj limitsObj = BSON( ShardFields::maxSize( s.getMaxSize() ) << 
                                      ShardFields::currSize( status.mapped() ) <<
                                      ShardFields::draining( s.isDraining()) );

            shardLimitsMap[ s.getName() ] = limitsObj;
        }

        //
        // 3. For each collection, check if the balancing policy recommends moving anything around.
        //

        for (vector<string>::const_iterator it = collections.begin(); it != collections.end(); ++it ) {
            const string& ns = *it;

            map< string,vector<BSONObj> > shardToChunksMap;
            cursor = conn.query( ShardNS::chunk , QUERY( "ns" << ns ).sort( "min" ) );
            while ( cursor->more() ){
                BSONObj chunk = cursor->next();
                vector<BSONObj>& chunks = shardToChunksMap[chunk["shard"].String()];
                chunks.push_back( chunk.getOwned() );
            }
            cursor.reset();

            if (shardToChunksMap.empty()) {
                log(1) << "balancer: skipping empty collection (" << ns << ")";
                continue;
            }
                
            for ( vector<Shard>::iterator i=allShards.begin(); i!=allShards.end(); ++i ){
                // this just makes sure there is an entry in shardToChunksMap for every shard
                Shard s = *i;
                shardToChunksMap[s.getName()].size();
            }

            CandidateChunk* p = _policy->balance( ns , shardLimitsMap , shardToChunksMap , _balancedLastTime );
            if ( p ) candidateChunks->push_back( CandidateChunkPtr( p ) );
        }
    }
Ejemplo n.º 3
0
    void Balancer::_doBalanceRound( DBClientBase& conn, vector<CandidateChunkPtr>* candidateChunks ) {
        assert( candidateChunks );

        //
        // 1. Check whether there is any sharded collection to be balanced by querying
        // the ShardsNS::collections collection
        //

        auto_ptr<DBClientCursor> cursor = conn.query( ShardNS::collection , BSONObj() );
        vector< string > collections;
        while ( cursor->more() ) {
            BSONObj col = cursor->nextSafe();

            // sharded collections will have a shard "key".
            if ( ! col["key"].eoo() )
                collections.push_back( col["_id"].String() );
        }
        cursor.reset();

        if ( collections.empty() ) {
            LOG(1) << "no collections to balance" << endl;
            return;
        }

        //
        // 2. Get a list of all the shards that are participating in this balance round
        // along with any maximum allowed quotas and current utilization. We get the
        // latter by issuing db.serverStatus() (mem.mapped) to all shards.
        //
        // TODO: skip unresponsive shards and mark information as stale.
        //

        vector<Shard> allShards;
        Shard::getAllShards( allShards );
        if ( allShards.size() < 2) {
            LOG(1) << "can't balance without more active shards" << endl;
            return;
        }

        map< string, BSONObj > shardLimitsMap;
        for ( vector<Shard>::const_iterator it = allShards.begin(); it != allShards.end(); ++it ) {
            const Shard& s = *it;
            ShardStatus status = s.getStatus();

            BSONObj limitsObj = BSON( ShardFields::maxSize( s.getMaxSize() ) <<
                                      LimitsFields::currSize( status.mapped() ) <<
                                      ShardFields::draining( s.isDraining() )  <<
                                      LimitsFields::hasOpsQueued( status.hasOpsQueued() )
                                    );

            shardLimitsMap[ s.getName() ] = limitsObj;
        }

        //
        // 3. For each collection, check if the balancing policy recommends moving anything around.
        //

        for (vector<string>::const_iterator it = collections.begin(); it != collections.end(); ++it ) {
            const string& ns = *it;

            map< string,vector<BSONObj> > shardToChunksMap;
            cursor = conn.query( ShardNS::chunk , QUERY( "ns" << ns ).sort( "min" ) );
            while ( cursor->more() ) {
                BSONObj chunk = cursor->nextSafe();
                if ( chunk["jumbo"].trueValue() )
                    continue;
                vector<BSONObj>& chunks = shardToChunksMap[chunk["shard"].String()];
                chunks.push_back( chunk.getOwned() );
            }
            cursor.reset();

            if (shardToChunksMap.empty()) {
                LOG(1) << "skipping empty collection (" << ns << ")";
                continue;
            }

            for ( vector<Shard>::iterator i=allShards.begin(); i!=allShards.end(); ++i ) {
                // this just makes sure there is an entry in shardToChunksMap for every shard
                Shard s = *i;
                shardToChunksMap[s.getName()].size();
            }

            CandidateChunk* p = _policy->balance( ns , shardLimitsMap , shardToChunksMap , _balancedLastTime );
            if ( p ) candidateChunks->push_back( CandidateChunkPtr( p ) );
        }
    }
Ejemplo n.º 4
0
    void Balancer::_doBalanceRound( DBClientBase& conn, vector<CandidateChunkPtr>* candidateChunks ) {
        verify( candidateChunks );

        //
        // 1. Check whether there is any sharded collection to be balanced by querying
        // the ShardsNS::collections collection
        //

        auto_ptr<DBClientCursor> cursor = conn.query(CollectionType::ConfigNS, BSONObj());

        if ( NULL == cursor.get() ) {
            warning() << "could not query " << CollectionType::ConfigNS
                      << " while trying to balance" << endl;
            return;
        }

        vector< string > collections;
        while ( cursor->more() ) {
            BSONObj col = cursor->nextSafe();

            // sharded collections will have a shard "key".
            if ( ! col[CollectionType::keyPattern()].eoo() &&
                 ! col[CollectionType::noBalance()].trueValue() ){
                collections.push_back( col[CollectionType::ns()].String() );
            }
            else if( col[CollectionType::noBalance()].trueValue() ){
                LOG(1) << "not balancing collection " << col[CollectionType::ns()].String()
                       << ", explicitly disabled" << endl;
            }

        }
        cursor.reset();

        if ( collections.empty() ) {
            LOG(1) << "no collections to balance" << endl;
            return;
        }

        //
        // 2. Get a list of all the shards that are participating in this balance round
        // along with any maximum allowed quotas and current utilization. We get the
        // latter by issuing db.serverStatus() (mem.mapped) to all shards.
        //
        // TODO: skip unresponsive shards and mark information as stale.
        //

        ShardInfoMap shardInfo;
        Status loadStatus = DistributionStatus::populateShardInfoMap(&shardInfo);

        if (!loadStatus.isOK()) {
            warning() << "failed to load shard metadata" << causedBy(loadStatus) << endl;
            return;
        }

        if (shardInfo.size() < 2) {
            LOG(1) << "can't balance without more active shards" << endl;
            return;
        }

        OCCASIONALLY warnOnMultiVersion( shardInfo );

        //
        // 3. For each collection, check if the balancing policy recommends moving anything around.
        //

        for (vector<string>::const_iterator it = collections.begin(); it != collections.end(); ++it ) {
            const string& ns = *it;

            OwnedPointerMap<string, OwnedPointerVector<ChunkType> > shardToChunksMap;
            cursor = conn.query(ChunkType::ConfigNS,
                                QUERY(ChunkType::ns(ns)).sort(ChunkType::min()));

            set<BSONObj> allChunkMinimums;

            while ( cursor->more() ) {
                BSONObj chunkDoc = cursor->nextSafe().getOwned();

                auto_ptr<ChunkType> chunk(new ChunkType());
                string errmsg;
                if (!chunk->parseBSON(chunkDoc, &errmsg)) {
                    error() << "bad chunk format for " << chunkDoc
                            << ": " << errmsg << endl;
                    return;
                }

                allChunkMinimums.insert(chunk->getMin().getOwned());
                OwnedPointerVector<ChunkType>*& chunkList =
                        shardToChunksMap.mutableMap()[chunk->getShard()];

                if (chunkList == NULL) {
                    chunkList = new OwnedPointerVector<ChunkType>();
                }

                chunkList->mutableVector().push_back(chunk.release());
            }
            cursor.reset();

            if (shardToChunksMap.map().empty()) {
                LOG(1) << "skipping empty collection (" << ns << ")";
                continue;
            }

            for (ShardInfoMap::const_iterator i = shardInfo.begin(); i != shardInfo.end(); ++i) {
                // this just makes sure there is an entry in shardToChunksMap for every shard
                OwnedPointerVector<ChunkType>*& chunkList =
                        shardToChunksMap.mutableMap()[i->first];

                if (chunkList == NULL) {
                    chunkList = new OwnedPointerVector<ChunkType>();
                }
            }

            DistributionStatus status(shardInfo, shardToChunksMap.map());

            // load tags
            Status result = clusterCreateIndex(TagsType::ConfigNS,
                                               BSON(TagsType::ns() << 1 << TagsType::min() << 1),
                                               true, // unique
                                               WriteConcernOptions::AllConfigs,
                                               NULL);

            if ( !result.isOK() ) {
                warning() << "could not create index tags_1_min_1: " << result.reason() << endl;
                continue;
            }

            cursor = conn.query(TagsType::ConfigNS,
                                QUERY(TagsType::ns(ns)).sort(TagsType::min()));

            vector<TagRange> ranges;

            while ( cursor->more() ) {
                BSONObj tag = cursor->nextSafe();
                TagRange tr(tag[TagsType::min()].Obj().getOwned(),
                            tag[TagsType::max()].Obj().getOwned(),
                            tag[TagsType::tag()].String());
                ranges.push_back(tr);
                uassert(16356,
                        str::stream() << "tag ranges not valid for: " << ns,
                        status.addTagRange(tr) );

            }
            cursor.reset();

            DBConfigPtr cfg = grid.getDBConfig( ns );
            if ( !cfg ) {
                warning() << "could not load db config to balance " << ns << " collection" << endl;
                continue;
            }

            // This line reloads the chunk manager once if this process doesn't know the collection
            // is sharded yet.
            ChunkManagerPtr cm = cfg->getChunkManagerIfExists( ns, true );
            if ( !cm ) {
                warning() << "could not load chunks to balance " << ns << " collection" << endl;
                continue;
            }

            // loop through tags to make sure no chunk spans tags; splits on tag min. for all chunks
            bool didAnySplits = false;
            for ( unsigned i = 0; i < ranges.size(); i++ ) {
                BSONObj min = ranges[i].min;

                min = cm->getShardKey().extendRangeBound( min, false );

                if ( allChunkMinimums.count( min ) > 0 )
                    continue;

                didAnySplits = true;

                log() << "ns: " << ns << " need to split on "
                      << min << " because there is a range there" << endl;

                ChunkPtr c = cm->findIntersectingChunk( min );

                vector<BSONObj> splitPoints;
                splitPoints.push_back( min );

                BSONObj res;
                if ( !c->multiSplit( splitPoints, res ) ) {
                    error() << "split failed: " << res << endl;
                }
                else {
                    LOG(1) << "split worked: " << res << endl;
                }
                break;
            }

            if ( didAnySplits ) {
                // state change, just wait till next round
                continue;
            }

            CandidateChunk* p = _policy->balance( ns, status, _balancedLastTime );
            if ( p ) candidateChunks->push_back( CandidateChunkPtr( p ) );
        }
    }
Ejemplo n.º 5
0
    void Balancer::_doBalanceRound( DBClientBase& conn, vector<CandidateChunkPtr>* candidateChunks ) {
        verify( candidateChunks );

        //
        // 1. Check whether there is any sharded collection to be balanced by querying
        // the ShardsNS::collections collection
        //

        auto_ptr<DBClientCursor> cursor = conn.query(CollectionType::ConfigNS, BSONObj());
        vector< string > collections;
        while ( cursor->more() ) {
            BSONObj col = cursor->nextSafe();

            // sharded collections will have a shard "key".
            if ( ! col[CollectionType::keyPattern()].eoo() &&
                 ! col[CollectionType::noBalance()].trueValue() ){
                collections.push_back( col[CollectionType::ns()].String() );
            }
            else if( col[CollectionType::noBalance()].trueValue() ){
                LOG(1) << "not balancing collection " << col[CollectionType::ns()].String()
                       << ", explicitly disabled" << endl;
            }

        }
        cursor.reset();

        if ( collections.empty() ) {
            LOG(1) << "no collections to balance" << endl;
            return;
        }

        //
        // 2. Get a list of all the shards that are participating in this balance round
        // along with any maximum allowed quotas and current utilization. We get the
        // latter by issuing db.serverStatus() (mem.mapped) to all shards.
        //
        // TODO: skip unresponsive shards and mark information as stale.
        //

        vector<Shard> allShards;
        Shard::getAllShards( allShards );
        if ( allShards.size() < 2) {
            LOG(1) << "can't balance without more active shards" << endl;
            return;
        }
        
        ShardInfoMap shardInfo;
        for ( vector<Shard>::const_iterator it = allShards.begin(); it != allShards.end(); ++it ) {
            const Shard& s = *it;
            ShardStatus status = s.getStatus();
            shardInfo[ s.getName() ] = ShardInfo( s.getMaxSize(),
                                                  status.mapped(),
                                                  s.isDraining(),
                                                  status.hasOpsQueued(),
                                                  s.tags()
                                                  );
        }

        //
        // 3. For each collection, check if the balancing policy recommends moving anything around.
        //

        for (vector<string>::const_iterator it = collections.begin(); it != collections.end(); ++it ) {
            const string& ns = *it;

            map< string,vector<BSONObj> > shardToChunksMap;
            cursor = conn.query(ChunkType::ConfigNS,
                                QUERY(ChunkType::ns(ns)).sort(ChunkType::min()));

            set<BSONObj> allChunkMinimums;

            while ( cursor->more() ) {
                BSONObj chunk = cursor->nextSafe().getOwned();
                vector<BSONObj>& chunks = shardToChunksMap[chunk[ChunkType::shard()].String()];
                allChunkMinimums.insert( chunk[ChunkType::min()].Obj() );
                chunks.push_back( chunk );
            }
            cursor.reset();

            if (shardToChunksMap.empty()) {
                LOG(1) << "skipping empty collection (" << ns << ")";
                continue;
            }

            for ( vector<Shard>::iterator i=allShards.begin(); i!=allShards.end(); ++i ) {
                // this just makes sure there is an entry in shardToChunksMap for every shard
                Shard s = *i;
                shardToChunksMap[s.getName()].size();
            }

            DistributionStatus status( shardInfo, shardToChunksMap );

            // load tags
            conn.ensureIndex(TagsType::ConfigNS,
                             BSON(TagsType::ns() << 1 << TagsType::min() << 1),
                             true);

            cursor = conn.query(TagsType::ConfigNS,
                                QUERY(TagsType::ns(ns)).sort(TagsType::min()));

            vector<TagRange> ranges;

            while ( cursor->more() ) {
                BSONObj tag = cursor->nextSafe();
                TagRange tr(tag[TagsType::min()].Obj().getOwned(),
                            tag[TagsType::max()].Obj().getOwned(),
                            tag[TagsType::tag()].String());
                ranges.push_back(tr);
                uassert(16356,
                        str::stream() << "tag ranges not valid for: " << ns,
                        status.addTagRange(tr) );

            }
            cursor.reset();

            DBConfigPtr cfg = grid.getDBConfig( ns );
            verify( cfg );
            ChunkManagerPtr cm = cfg->getChunkManager( ns );
            verify( cm );

            // loop through tags to make sure no chunk spans tags; splits on tag min. for all chunks
            bool didAnySplits = false;
            for ( unsigned i = 0; i < ranges.size(); i++ ) {
                BSONObj min = ranges[i].min;

                min = cm->getShardKey().extendRangeBound( min, false );

                if ( allChunkMinimums.count( min ) > 0 )
                    continue;

                didAnySplits = true;

                log() << "ns: " << ns << " need to split on "
                      << min << " because there is a range there" << endl;

                ChunkPtr c = cm->findIntersectingChunk( min );

                vector<BSONObj> splitPoints;
                splitPoints.push_back( min );

                BSONObj res;
                if ( !c->multiSplit( splitPoints, res ) ) {
                    error() << "split failed: " << res << endl;
                }
                else {
                    LOG(1) << "split worked: " << res << endl;
                }
                break;
            }

            if ( didAnySplits ) {
                // state change, just wait till next round
                continue;
            }

            CandidateChunk* p = _policy->balance( ns, status, _balancedLastTime );
            if ( p ) candidateChunks->push_back( CandidateChunkPtr( p ) );
        }
    }