refactor: Optimize IndexedPriorityQueue::addOrUpdate 20 times faster #11955
+368
−318
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Summary:
Optimize
IndexedPriorityQueue
to use more compact data structures (binary heap) to leverage cache locality and avoid unnecessary memory allocations.addOrUpdate
is now about 20 times faster for large data (~1 million elements). This allows us to replace the custom heap implementation inApproxMostFrequentStreamSummary
withIndexedPriorityQueue
.Note that
pop
becomes about twice slower in the new version. This is expected because we shift some of the reordering cost from insertion time to pop time. This shall be good because for eachpop
, we have at least one correspondingaddOrUpdate
which guarantees net performance gain, and in most of the case we donot even have
pop
on critical path (e.g. in case ofApproxMostFrequentStreamSummary
).Differential Revision: D67626564