Re: [RFC 03/18] memcontrol: present maximum used memory also for cgroup-v2

[Michal Hocko <mhocko@kernel.org>]

On Tue 14-06-16 17:15:06, Topi Miettinen wrote:
> On 06/14/16 16:04, Johannes Weiner wrote:
[...]
> > I didn't catch the coverletter, though. It makes sense to CC
> > recipients of any of those patches on the full series, including the
> > cover, since even though we are specialized in certain areas of the
> > code, many of us are interested in the whole picture of addressing a
> > problem, and not just the few bits in our area without more context.
> > 
> 
> Thank you for this nice explanation. I suppose "git send-email
> --cc-cmd=scripts/get_maintainer.pl" doesn't do this.

No it doesn't. What I do for this kind of series is the following. Put
an explicit CC (acked, reviews etc...) to each patch. git format-patch
$RANGE and then
$ git send-email --cc-cmd=./cc-cmd-only-cover.sh $DEFAULT_TO_CC --compose *.patch

$ cat cc-cmd-only-cover.sh
#!/bin/bash

if [[ $1 == *gitsendemail.msg* || $1 == *cover-letter* ]]; then
        grep '<.*@.*>' -h *.patch | sed 's/^.*: //' | sort | uniq
fi

A bit error prone because you have to cleanup any previous patch files
from the directory but works more or less well for me.

s 
> > As far as the memcg part of this series goes, one concern is that page
> > cache is trimmed back only when there is pressure, so in all but very
> > few cases the high watermark you are introducing will be pegged to the
> > configured limit. It doesn't give a whole lot of insight.
> > 
> 
> So using the high watermark would not give a very useful starting point
> for the user who wished to configure the memory limit? What else could
> be used instead?

we have an event notification mechanism. In v1 it is vmpressure and v2
you will get a notification when the high/max limit is hit or when we
hit the oom.
-- 
Michal Hocko
SUSE Labs