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Date:   Wed, 27 Jan 2021 12:27:03 +0100
From:   Michal Hocko <mhocko@suse.com>
To:     Christian =?iso-8859-1?Q?K=F6nig?= <christian.koenig@amd.com>
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Subject: Re: [PATCH] procfs/dmabuf: Add /proc/<pid>/task/<tid>/dmabuf_fds
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On Wed 27-01-21 12:01:55, Christian K?nig wrote:
[...]
> Some years ago I've proposed an change to improve the OOM killer to take
> into account how much memory is reference through special file descriptors
> like device drivers or DMA-buf.
> 
> But that never want anywhere because of concerns that this would add to much
> overhead to the OOM killer.

I have to admit I do not remember such a discussion. There were many on
the related topic, concerns were mostly about a proper accounting of
shared resources or locking required to gain the information. I do not
remember overhead as being the main concern as oom is a real cold path.

Anyway, if you want to revamp those patches then feel free to CC me and
we can discuss further. I do not want to hijack this thread by an
unrelated topic.
-- 
Michal Hocko
SUSE Labs