Re: [PATCH 1/3] memcg: extract memcg_vmstats from struct mem_cgroup

From: Shakeel Butt
Date: Fri Sep 09 2022 - 12:12:13 EST


On Thu, Sep 8, 2022 at 5:26 PM Michal Koutný <mkoutny@xxxxxxxx> wrote:
>
> Hi.
>
> On Wed, Sep 07, 2022 at 04:35:35AM +0000, Shakeel Butt <shakeelb@xxxxxxxxxx> wrote:
> > This is a preparatory patch to reduce the memory overhead of memory
> > cgroup. The struct memcg_vmstats is the largest object embedded into the
> > struct mem_cgroup.
> > This patch extracts struct memcg_vmstats from struct
> > mem_cgroup to ease the following patches in reducing the size of struct
> > memcg_vmstats.
>
> Is the reason for the extraction just moving things away from the header
> file?
> Or is the separate allocation+indirection somehow beneficial wrt, e.g.
> fragmentation?
>

The main reason was to move away from the head file. I have not yet
measured the performance impact of these changes. I am planning to
rearrange struct mem_cgroup and will do some performance tests after
that.