Re: [PATCH v1] ringbuffer: Don't choose the process with adj equal OOM_SCORE_ADJ_MIN

From: Steven Rostedt <rostedt@goodmis.org>
To: Michal Hocko <mhocko@kernel.org>
Cc: Zhaoyang Huang <huangzhaoyang@gmail.com>,
	Ingo Molnar <mingo@kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Joel Fernandes <joelaf@google.com>
Subject: Re: [PATCH v1] ringbuffer: Don't choose the process with adj equal OOM_SCORE_ADJ_MIN
Date: Tue, 10 Apr 2018 08:36:25 -0400	[thread overview]
Message-ID: <20180410083625.2c904ab2@gandalf.local.home> (raw)
In-Reply-To: <20180410122706.GH21835@dhcp22.suse.cz>

On Tue, 10 Apr 2018 14:27:06 +0200
Michal Hocko <mhocko@kernel.org> wrote:

> I would rather that the code outside of MM not touch implementation
> details like OOM_SCORE_ADJ_MIN. It is really hard to get rid of abusers
> whenever you try to change something in MM then. Especially when the
> usecase is quite dubious.

Fair enough. I was reluctant to use the OOM_SCORE_ADJ_MIN in this case.

Perhaps I can create an option that lets users decide how they want to
allocate.

For people like Joel, it will try hard (by default) and set oom_origin,
but the user could also set an option "no_mem_reclaim", where it will
not set oom_origin, but will also use NORETRY as well, where it wont
trigger OOM and will not be the designated victim of OOM. But it will
likely not allocate memory if the system is under heavy use. Then for
Zhaoyang's tests, all he has to do is to set that option (or clear it,
if the option is "mem_reclaim", which is what I'll probably call it).

-- Steve