On Mon, 22 Feb 2021 17:56:25 GMT, Jonathan Gibbons <j...@openjdk.org> wrote:
> there is very little change in the utilization of the background writer as a > function of the question size Did you mean "queue size"? If so, then I also noticed that in my observation no. 2 under the results table here: https://github.com/openjdk/jdk/pull/2665#issuecomment-783503529 For me, utilization roughly stayed at the same 20% mark regardless of the number of queued tasks. To me, this indicates conflicting readings. On the one hand, we have 20% of "utilization". On the other hand, 1/4 of attempts to acquire a permit to hand over a task to the executor fail. Put differently, in 1/4 of the cases the producer waits for the consumer who works at 20% capacity. Why? I think we should use suitable tools (e.g. profilers) and/or ask experts in performance. If nothing else, this will help us diagnose such issues in the future. ------------- PR: https://git.openjdk.java.net/jdk/pull/2665
