public WALCountersHolder pushWALCounters ( WALCountersHolder holder ) { if ( snapshot == null ) return holder ; if ( snapshot . walCountersHolder == null ) return holder ; if ( holder == null ) holder = new WALCountersHolder ( ) ; snapshot . walCountersHolder . pushData ( holder ) ; return holder ; }
Takes write ahead log data from last snapshot and aggregates them with data passed inside method as parameter . Result of aggregation of performance data is returned inside of passed in performance data and as result of this method call .