fix: evict stale upstream countMap entries in LeastActiveLoadBalance - #6900
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fix: evict stale upstream countMap entries in LeastActiveLoadBalance #6900juicewcode wants to merge 1 commit into
juicewcode wants to merge 1 commit into
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…pache#6891) The countMap in LeastActiveLoadBalance accumulates an entry for every upstream domain ever observed, but had no removal path: when an upstream was removed from the list, its entry lingered indefinitely, leaking memory proportionally to historical upstream churn and adding O(n) scan overhead to every doSelect call. Now stale entries whose domains are absent from the current upstream list are removed before the least active domain is selected.
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Fixes #6891
LeastActiveLoadBalance.countMap. Previously entries were only added and never removed, so an upstream's entry lingered forever after it was taken out of the list, causing unbounded memory growth proportional to historical upstream churn and O(n) scan overhead on every selection. Now stale entries whose domains are absent from the current upstream list are evicted viacountMap.keySet().retainAll(domainMap.keySet())before selection.testRemoveStaleCountMapEntriestoLeastActiveLoadBalanceTest. It registers two upstreams, removes one, and asserts the removed upstream'scountMapentry is cleaned up while the remaining one is kept.Make sure that:
./mvnw clean install -Dmaven.javadoc.skip=true.