Messages in this thread | | | Date | Tue, 6 Dec 2016 15:20:55 +1100 | From | Paul Mackerras <> | Subject | Re: [PATCH 00/10] vtime: Delay cputime accounting to tick |
| |
On Tue, Dec 06, 2016 at 03:32:13AM +0100, Frederic Weisbecker wrote: > This follows up Martin Schwidefsky's patch which propose to delay > cputime accounting to the tick in order to minimize the calls to > account_system_time() and alikes as these functions can carry quite some > overhead: > > http://lkml.kernel.org/r/20161121111728.13a0a3db@mschwide > > The set includes Martin's patch, rebased on top of tip:sched/core and > latest s390 changes, and extends it to the other implementations of > CONFIG_VIRT_CPU_ACCOUNTING_NATIVE (powerpc and ia64) along with a few > core changes to adapt the whole. > > Only built-tested though as I don't have access to any of these archs.
The patches look reasonable at a quick look. I assume that to test them, we would want to run a guest in an overcommitted system, so as to get some steal time. Do you have any more specific suggestions as to what to run as a test? Just run some benchmark and see if the user/system/irq times look reasonable? Or do you have something more quantitative?
Paul.
| |