public final class Generic2AggPooledTopNScannerPrototype extends Object implements Generic2AggPooledTopNScanner
Constructor and Description |
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Generic2AggPooledTopNScannerPrototype() |
Modifier and Type | Method and Description |
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long |
scanAndAggregate(DimensionSelector dimensionSelector,
BufferAggregator aggregator1,
int aggregator1Size,
BufferAggregator aggregator2,
int aggregator2Size,
Cursor cursor,
int[] positions,
ByteBuffer resultsBuffer)
Any changes to this method should be coordinated with
TopNUtils , PooledTopNAlgorithm.computeSpecializedScanAndAggregateImplementations() and downstream methods. |
public Generic2AggPooledTopNScannerPrototype()
public long scanAndAggregate(DimensionSelector dimensionSelector, BufferAggregator aggregator1, int aggregator1Size, BufferAggregator aggregator2, int aggregator2Size, Cursor cursor, int[] positions, ByteBuffer resultsBuffer)
TopNUtils
, PooledTopNAlgorithm.computeSpecializedScanAndAggregateImplementations()
and downstream methods.
It should be checked with a tool like https://github.com/AdoptOpenJDK/jitwatch that C2 compiler output for this
method doesn't have any method calls in the while loop, i. e. all method calls are inlined. To be able to see
assembly of this method in JITWatch and other similar tools, PooledTopNAlgorithm.specializeGeneric2AggPooledTopN
should be turned off. Note that in this case the benchmark
should be "naturally monomorphic", i. e. execute this method always with the same runtime shape.
If the while loop contains not inlined method calls, it should be considered as a performance bug.scanAndAggregate
in interface Generic2AggPooledTopNScanner
aggregator1Size
- number of bytes required by aggregator1 for a single aggregationaggregator2Size
- number of bytes required by aggregator2 for a single aggregationpositions
- a cache for positions in resultsBuffer, where specific (indexed) dimension values are aggregatedCopyright © 2011–2018. All rights reserved.