* Miroslav Lichvar: > On Tue, Jul 12, 2022 at 09:26:14AM +0200, Florian Weimer wrote: >> * Marius Schwarz: >> > and I don't think, this tasks needs to read the clock that often too. >> >> strace shouldn't see a system call here because clock_gettime should be >> handled in the vDSO. This suggests something is wrong with the system >> (unless it's some obscure variant that really doesn't have vDSO support). > > It doesn't necessarily have to be something wrong with the system. > The vDSO clock_gettime() works only with specific clocksources, > typically TSC on x86_64. On some older HW it's not reliable enough to > be selected by the kernel, or it could be a VM which doesn't have one > that would work with migrations, etc. True, but I suspect a Xeon E5-2620 v4 is recent enough to have a stable TSC (I see nonstop_tsc and constant_tsc in /proc/cpuinfo for some random lab system, for a start). So I suspect that virtualization is masking it, or otherwise interfering with the TSC. Thanks, Florian _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam on the list, report it: https://pagure.io/fedora-infrastructure
