snapshots.h

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// snapshots.h

#pragma once
#include "../../pch.h"
#include "../jsobj.h"
#include "top.h"
#include "../../util/background.h"

namespace mongo {

    class SnapshotThread;

    class SnapshotData {
        void takeSnapshot();

        unsigned long long _created;
        Top::CollectionData _globalUsage;
        unsigned long long _totalWriteLockedTime; // micros of total time locked
        Top::UsageMap _usage;

        friend class SnapshotThread;
        friend class SnapshotDelta;
        friend class Snapshots;
    };

    class SnapshotDelta {
    public:
        SnapshotDelta( const SnapshotData& older , const SnapshotData& newer );

        unsigned long long start() const {
            return _older._created;
        }

        unsigned long long elapsed() const {
            return _elapsed;
        }

        unsigned long long timeInWriteLock() const {
            return _newer._totalWriteLockedTime - _older._totalWriteLockedTime;
        }
        double percentWriteLocked() const {
            double e = (double) elapsed();
            double w = (double) timeInWriteLock();
            return w/e;
        }

        Top::CollectionData globalUsageDiff();
        Top::UsageMap collectionUsageDiff();

    private:
        const SnapshotData& _older;
        const SnapshotData& _newer;

        unsigned long long _elapsed;
    };

    class Snapshots {
    public:
        Snapshots(int n=100);

        const SnapshotData* takeSnapshot();

        int numDeltas() const { return _stored-1; }

        const SnapshotData& getPrev( int numBack = 0 );
        auto_ptr<SnapshotDelta> computeDelta( int numBack = 0 );


        void outputLockInfoHTML( stringstream& ss );
    private:
        mongo::mutex _lock;
        int _n;
        boost::scoped_array<SnapshotData> _snapshots;
        int _loc;
        int _stored;
    };

    class SnapshotThread : public BackgroundJob {
    public:
        virtual string name() const { return "snapshot"; }
        void run();
    };

    extern Snapshots statsSnapshots;
    extern SnapshotThread snapshotThread;


}

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mongodb
Author(s): Nate Koenig
autogenerated on Fri Jan 11 12:15:19 2013