[ https://issues.apache.org/jira/browse/HARMONY-5396?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12568067#action_12568067 ] 

Aleksey Shipilev commented on HARMONY-5396:
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I think the performance of ValueProfiler is only influence cold methods since hot recompiled methods have no value profiling. And so, we should only care about fast startup workloads, where code is relatively cold to be influenced with value profiling. That mean, we really don't care about long benchmarks.

Even though we care about short benchmarks, several subsequent branches is better than locking on mutex or atomic. 
May be we might try to measure Eclipse startup time in -Xem:server to have strict data.

> [drlvm][em] excess ValueProfiler locking causes degradation on JITted code with profiling
> -----------------------------------------------------------------------------------------
>
>                 Key: HARMONY-5396
>                 URL: https://issues.apache.org/jira/browse/HARMONY-5396
>             Project: Harmony
>          Issue Type: Improvement
>          Components: DRLVM
>            Reporter: Aleksey Shipilev
>            Assignee: Egor Pasko
>         Attachments: 0001-ValueProfileCollector-refactoring-to-separate-FirstN-and-Divided-methods.txt, 0002-value-profiling-options-locked-flagged_all-flagged_insert-unsafe.txt, 0002-ValueProfileCollector-implementing-locking-strategies.txt, 0003-value-profiling-options-locked-flagged_all-flagged_insert-unsafe.txt, HARMONY-5396-syncTie.patch
>
>
> During investigation of serious slowdown in some microbenchmark, excess locking in ValueProfiler was identified. 
> Please see Harmony-dev thread for the details: http://markmail.org/message/tatsfbyb7eb3q3rr

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