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Matthias Pohl commented on FLINK-32410: --------------------------------------- [~srichter] is this an ongoing effort? Looks like the PR made it into master and release-1.18 with [ab9445ac|https://github.com/apache/flink/commit/ab9445ac] and we could set the fixVersion to 1.18.0 and close this issue? > Allocate hash-based collections with sufficient capacity for expected size > -------------------------------------------------------------------------- > > Key: FLINK-32410 > URL: https://issues.apache.org/jira/browse/FLINK-32410 > Project: Flink > Issue Type: Improvement > Reporter: Stefan Richter > Assignee: Stefan Richter > Priority: Major > Labels: pull-request-available, stale-assigned > Fix For: 1.19.0 > > > The JDK API to create hash-based collections for a certain capacity is > arguable misleading because it doesn't size the collections to "hold a > specific number of items" like you'd expect it would. Instead it sizes it to > hold load-factor% of the specified number. > For the common pattern to allocate a hash-based collection with the size of > expected elements to avoid rehashes, this means that a rehash is essentially > guaranteed. > We should introduce helper methods (similar to Guava's > `Maps.newHashMapWithExpectedSize(int)`) for allocations for expected size and > replace the direct constructor calls with those. -- This message was sent by Atlassian Jira (v8.20.10#820010)