Messages in this thread | | | From | Andi Kleen <> | Subject | Re: [PATCH] Reduce vm_stat cacheline contention in __vm_enough_memory | Date | Thu, 13 Oct 2011 08:59:49 -0700 |
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Mel Gorman <mel@csn.ul.ie> writes: > > If vm_enough_memory is being heavily hit as well, it implies that this > workload is mmap-intensive which is pretty inefficient in itself. I
Saw it with tmpfs originally. No need to be mmap intensive. Just do lots of IOs on tmpfs.
> guess it would also apply to workloads that are malloc-intensive for > large buffers but I'd expect the cache line bounces to only dominate if > there was little or no computation on the resulting buffers.
I think you severly underestimate the costs of bouncing cache lines on >2S.
> As a result, I wonder how realistic is this test workload and who useful > fixing this problem is in general?
It's kind of bad if tmpfs doesn't scale.
-Andi
-- ak@linux.intel.com -- Speaking for myself only
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