On Sat, Mar 07, 2020 at 10:46:34AM -0500, Tom Lane wrote: > Julien Rouhaud <rjuju...@gmail.com> writes: > > On Sat, Mar 07, 2020 at 10:41:42AM +0900, Michael Paquier wrote: > >> On Fri, Mar 06, 2020 at 02:15:47PM +0100, Julien Rouhaud wrote: > >>> Here's a patch to add an optional "timeout val" clause to > >>> isolationtester's > >>> step definition. When used, isolationtester will actively wait on the > >>> query > >>> rather than continuing with the permutation next step, and will issue a > >>> cancel > >>> once the defined timeout is reached. > > >> One problem with this approach is that it does address the stability > >> of the test on very slow machines, and there are some of them in the > >> buildfarm. > > > Looking at timeouts.spec and e.g. a7921f71a3c, it seems that we already > > chose > > to fix this problem by having a timeout long enough to statisfy the slower > > buildfarm members, even when running on fast machines, so I assumed that the > > same approach could be used here. > > The arbitrarily-set timeouts that exist in some of the isolation tests > are horrid kluges that have caused us lots of headaches in the past > and no doubt will again in the future. Aside from occasionally failing > when a machine is particularly overloaded, they cause the tests to > take far longer than necessary on decently-fast machines.
Yeah, I have no doubt that it has been a pain, and this patch is clearly not a bullet-proof solution. > So ideally > we'd get rid of those entirely in favor of some more-dynamic approach. > Admittedly, I have no proposal for what that would be. The fault injection framework that was previously discussed would cover most of the usecase I can think of, but that's a way bigger project. > But adding yet > more ways to set a (guaranteed-to-be-wrong) timeout seems like the > wrong direction to be going in. Fair enough, I'll mark the patch as rejected then. > What's the actual need that you're trying to deal with? Testing the correct behavior of non trivial commands, such as CIC/reindex concurrently, that fails during the execution.
