mad commented on PR #245: URL: https://github.com/apache/commons-pool/pull/245#issuecomment-1739285348
I'll try to explain why this is required. Some database have transactions; in transactions, entities are created that can be reused in case of multithreading (cursors). To minimize the number of cursors (and their creation), a pool of objects is used In the case of a large number of transactions, the cost of initializing the stack trace becomes noticeable. The external pool is not convenient to hold, because its lifetime is equal to the transaction lifetime Benchmark result (https://gist.github.com/mad/91e7b587cd7677ef04139d805219e318) ``` Benchmark (withStackTrace) Mode Cnt Score Error Units PoolBench.bench true thrpt 87312.389 ops/s PoolBench.bench:·stack true thrpt NaN --- PoolBench.bench false thrpt 350373.113 ops/s PoolBench.bench:·stack false thrpt NaN --- ``` Profiling ``` w/ stacktrace ....[Thread state: RUNNABLE]........................................................................ 25.0% 33.3% <stack is empty, everything is filtered?> 25.0% 33.3% com.intellij.rt.execution.application.AppMainV2$1.run 15.6% 20.9% org.apache.commons.pool3.impl.BaseGenericObjectPool.getStackTrace 5.1% 6.8% org.apache.commons.pool3.impl.BaseGenericObjectPool$StatsStore.<init> 2.8% 3.7% org.apache.commons.pool3.impl.BaseGenericObjectPool.<init> 1.2% 1.6% org.apache.commons.pool3.impl.BaseGenericObjectPool.setEvictionPolicy 0.1% 0.1% org.apache.commons.pool3.impl.LinkedBlockingDeque.interuptTakeWaiters 0.0% 0.1% org.apache.commons.pool3.impl.BaseGenericObjectPool.setEvictionPolicyClassName 0.0% 0.1% org.apache.commons.pool3.impl.BaseGenericObjectPool$StatsStore.lambda$new$0 0.0% 0.0% com.bic.jmh.PoolBench.bench 0.1% 0.1% <other> w/o stacktrace ....[Thread state: RUNNABLE]........................................................................ 25.0% 33.3% <stack is empty, everything is filtered?> 25.0% 33.3% com.intellij.rt.execution.application.AppMainV2$1.run 19.9% 26.5% org.apache.commons.pool3.impl.BaseGenericObjectPool$StatsStore.<init> 4.0% 5.4% org.apache.commons.pool3.impl.BaseGenericObjectPool.setEvictionPolicy 0.6% 0.9% com.bic.jmh.PoolBench.bench 0.2% 0.3% org.apache.commons.pool3.impl.BaseGenericObjectPool.setEvictionPolicyClassName 0.2% 0.2% org.apache.commons.pool3.impl.BaseGenericObjectPool$StatsStore.lambda$new$0 0.0% 0.0% com.bic.jmh.generated.PoolBench_bench_jmhTest.bench_thrpt_jmhStub 0.0% 0.0% org.apache.commons.pool3.impl.GenericObjectPoolConfig.<init> 0.0% 0.0% org.apache.commons.pool3.impl.GenericObjectPool.<init> ``` -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
