On Fri, Jan 6, 2012 at 8:55 AM, Akemi Yagi <[email protected]> wrote: > On Fri, Jan 6, 2012 at 8:55 AM, Robin Price II <[email protected]> wrote: >> Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=765720 >> >> This is private due to private information from customer use cases. If you >> need further details, I would highly encourage you to contact Red Hat >> support or your TAM. >> >> Here is the initial information opened in the BZ: >> >> "The following patch is in urgent fix for Linus branch, which avoid the >> unnecessary overflow in sched_clock otherwise kernel will crash after >> 209~250 days. >> >> http://git.kernel.org/?p=linux/kernel/git/tip/tip.git;a=patch;h=4cecf6d401a01d054afc1e5f605bcbfe553cb9b9 >> >> In hundreds of days, the __cycles_2_ns calculation in sched_clock >> has an overflow. cyc * per_cpu(cyc2ns, cpu) exceeds 64 bits, causing the >> final value to become zero. We can solve this without losing any precision. >> We can decompose TSC into quotient and remainder of division by the scale >> factor, and then use this to convert TSC into nanoseconds." >> >> ~rp > > Thank you for this post to let us know that Red Hat is now taking care > of this issue.
Just a note to add that there is a KB article for this issue: https://access.redhat.com/kb/docs/DOC-69254 "sched_clock() overflow after 208.5 days in Linux Kernel" Akemi _______________________________________________ rhelv6-list mailing list [email protected] https://www.redhat.com/mailman/listinfo/rhelv6-list
