On Fri, Feb 3, 2023 at 4:21 PM Amit Kapila <amit.kapil...@gmail.com> wrote: > > On Fri, Feb 3, 2023 at 6:41 AM Peter Smith <smithpb2...@gmail.com> wrote: > > > > On Thu, Feb 2, 2023 at 7:21 PM Takamichi Osumi (Fujitsu) > > <osumi.takami...@fujitsu.com> wrote: > > > > > ... > > > > > > > > > > Besides, I am not sure it's a stable test to check the log. Is it > > > > possible that there's > > > > no such log on a slow machine? I modified the code to sleep 1s at the > > > > beginning > > > > of apply_dispatch(), then the new added test failed because the server > > > > log > > > > cannot match. > > > To get the log by itself is necessary to ensure > > > that the delay is conducted by the apply worker, because we emit the > > > diffms > > > only if it's bigger than 0 in maybe_apply_delay(). If we omit the step, > > > we are not sure the delay is caused by other reasons or the time-delayed > > > feature. > > > > > > As you mentioned, it's possible that no log is emitted on slow machine. > > > Then, > > > the idea to make the test safer for such machines should be to make the > > > delayed time longer. > > > But we shortened the delay time to 1 second to mitigate the long test > > > execution time of this TAP test. > > > So, I'm not sure if it's a good idea to make it longer again. > > > > I think there are a couple of things that can be done about this problem: > > > > 1. If you need the code/test to remain as-is then at least the test > > message could include some comforting text like "(this can fail on > > slow machines when the delay time is already exceeded)" so then a test > > failure will not cause undue alarm. > > > > 2. Try moving the DEBUG2 elog (in function maybe_apply_delay) so that > > it will *always* log the remaining wait time even if that wait time > > becomes negative. Then I think the test cases can be made > > deterministic instead of relying on good luck. This seems like the > > better option. > > > > I don't understand why we have to do any of this instead of using 3s > as min_apply_delay similar to what we are doing in > src/test/recovery/t/005_replay_delay. Also, I think we should use > exactly the same way to verify the test even though we want to keep > the log level as DEBUG2 to check logs in case of any failures. >
IIUC the reasons are due to conflicting requirements. e.g. - A longer delay like 3s might work better for testing this feature, but OTOH - A longer delay will also cause the whole BF execution to take longer ------ Kind Regards, Peter Smith. Fujitsu Australia.
