On Fri, 30 Sep 2022 09:10:05 GMT, Jaikiran Pai <[email protected]> wrote:
> Can I please get a review for this test-only change which proposes to improve > the test run duration of `java/net/vthread/HttpALot.java` test, on Linux? > This relates to https://bugs.openjdk.org/browse/JDK-8294610 > > Experiments have shown that on Linux, due to delayed TCP ACKs from the client > (for some previous sent data/packet), the server sent response waits for the > ACKs before sending the response data (in a TCP packet). Each delayed ACK is > 40 milli seconds and given the number of requests this test (intentionally) > issues, the delay accumulates causing the test to take longer duration. > > With the change in this PR, the test completes in around 6 to 8 seconds on a > Linux system as compared to 60 odd seconds previously on the same setup. This > change hasn't shown any negative impact on macos (which continues to run this > test in around 5 to 6 seconds like previously). I will trigger some runs in > our CI setup to make sure this works as expected in all other OS too. > > As noted in the linked JBS issue, additional experiments to see if anything > can be improved in the JDK network layer will be carried out separately, > outside the context of this test. Good sleuthing Jaikiran! LGTM. TIL; jtreg has an `@comment` tag! ------------- Marked as reviewed by dfuchs (Reviewer). PR: https://git.openjdk.org/jdk/pull/10504
