Re: [PATCH v2] tmpfs not interleaving properly

[Andrew Morton]

On Thu, 31 May 2012 09:39:17 -0500
Nathan Zimmer <nzimmer@xxxxxxx> wrote:

> When tmpfs has the memory policy interleaved it always starts allocating at each
> file at node 0.  When there are many small files the lower nodes fill up
> disproportionately.
> This patch attempts to spread out node usage by starting files at nodes other
> then 0.  I disturbed the addr parameter since alloc_pages_vma will only use it
> when the policy is MPOL_INTERLEAVE.  Random was picked over using another
> variable which would require some sort of contention management.

The patch title is a bit scummy ;) It describes a kernel problem, not
the patch.  I renamed it to "tmpfs: implement NUMA node interleaving".

It looks nice and simple

> Cc: stable@xxxxxxxxxxxxxxx

We could probably sneak this past Greg, but should we?  It's a feature
and a performance enhancement.  Such things are not normally added to
-stable.  If there were some nice performance improvements in workloads
which our users care about then I guess we could backport it.

But you've provided us with no measurements at all, hence no reason to
backport it.


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/