Re: [PATCH mm-unstable v1 0/2] Track pages allocated for struct

From: Roman Gushchin
Date: Wed Nov 13 2024 - 14:18:54 EST


On Thu, Oct 31, 2024 at 04:06:04PM -0700, Andrew Morton wrote:
> hm.
>
> On Thu, 31 Oct 2024 22:45:49 +0000 Kinsey Ho <kinseyho@xxxxxxxxxx> wrote:
>
> > We noticed high overhead for pages allocated for struct swap_cgroup in
> > our fleet.
>
> This is scanty. Please describe the problem further.
>
> > This patchset adds the number of pages allocated for struct
> > swap_cgroup to vmstat. This can be a useful metric for identifying
> > unneeded overhead on systems which configure swap.
>
> Possibly dumb question: can we switch swap_cgroup_prepare to kmalloc()
> (or kmem-cache_alloc()) and use slab's accounting to satisfy this
> requirement?

Or vzalloc/kvmalloc(), which are used for allocating the rest of swap-related
meta-data.