Messages in this thread | | | Date | Wed, 6 Oct 2004 12:39:59 -0700 | From | Andrew Morton <> | Subject | Re: Default cache_hot_time value back to 10ms |
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"Chen, Kenneth W" <kenneth.w.chen@intel.com> wrote: > > Andrew Morton wrote on Tuesday, October 05, 2004 9:51 PM > > > Nick Piggin <nickpiggin@yahoo.com.au> wrote: > > > I'd say it is probably too low level to be a useful tunable (although > > > for testing I guess so... but then you could have *lots* of parameters > > > tunable). > > > > This tunable caused an 11% performance difference in (I assume) TPCx. > > That's a big deal, and people will want to diddle it. > > > > If one number works optimally for all machines and workloads then fine. > > > > But yes, avoiding a tunable would be nice, but we need a tunable to work > > out whether we can avoid making it tunable ;) > > > > Not that I'm soliciting patches or anything. I'll duck this one for now. > > Andrew, can I safely interpret this response as you are OK with having > cache_hot_time set to 10 ms for now?
I have a lot of scheduler changes queued up and I view this change as being not very high priority. If someone sends a patch to update -mm then we can run with that, however Ingo's auto-tuning seems a far preferable approach.
> And you will merge this change for 2.6.9?
I was not planning on doing so, but could be persuaded, I guess.
It's very, very late for this and subtle CPU scheduler regressions tend to take a long time (weeks or months) to be identified. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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