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SubjectRe: [PATCH] Reduce vm_stat cacheline contention in __vm_enough_memory
Mel Gorman <> 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.


-- -- Speaking for myself only

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