mongodb: balance.h Source File

00001 //@file balance.h
00002 
00019 #pragma once
00020 
00021 #include "../pch.h"
00022 #include "../util/background.h"
00023 #include "../client/dbclient.h"
00024 #include "balancer_policy.h"
00025 
00026 namespace mongo {
00027 
00037     class Balancer : public BackgroundJob {
00038     public:
00039         Balancer();
00040         virtual ~Balancer();
00041 
00042         // BackgroundJob methods
00043 
00044         virtual void run();
00045 
00046         virtual string name() const { return "Balancer"; }
00047 
00048     private:
00049         typedef BalancerPolicy::ChunkInfo CandidateChunk;
00050         typedef shared_ptr<CandidateChunk> CandidateChunkPtr;
00051 
00052         // hostname:port of my mongos
00053         string _myid;
00054 
00055         // time the Balancer started running
00056         time_t _started;
00057 
00058         // number of moved chunks in last round
00059         int _balancedLastTime;
00060 
00061         // decide which chunks to move; owned here.
00062         BalancerPolicy* _policy;
00063 
00071         bool _init();
00072 
00080         void _doBalanceRound( DBClientBase& conn, vector<CandidateChunkPtr>* candidateChunks );
00081 
00088         int _moveChunks( const vector<CandidateChunkPtr>* candidateChunks );
00089 
00095         void _ping( DBClientBase& conn );
00096 
00100         bool _checkOIDs();
00101 
00102     };
00103 
00104     extern Balancer balancer;
00105 }