Messages in this thread | | | Date | Thu, 19 Mar 2015 10:59:08 -0700 | Subject | Re: [PATCH v2] sched, timer: Use atomics for thread_group_cputimer to improve scalability | From | Linus Torvalds <> |
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On Thu, Mar 19, 2015 at 10:21 AM, Jason Low <jason.low2@hp.com> wrote: > > I tested this patch on a 32 bit ARM system with 4 cores. Using the > generic 64 bit atomics, I did not see any performance change with this > patch, and the relevant functions (account_group_*_time(), ect...) don't > show up in perf reports.
Ok.
> One factor might be because locking/cacheline contention isn't as > apparent on smaller systems to begin with, and lib/atomic64.c also > mentions that "this is expected to used on systems with small numbers of > CPUs (<= 4 or so)".
Yeah, that's probably a valid argument anyway - 32-bit systems aren't really going to be multi-node big systems any more.
So I'm ok with the patch,
Linus
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