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Date: Wed, 4 Apr 2018 12:13:26 -0400
From: Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [PATCH] ring-buffer: Add set/clear_current_oom_origin() during
 allocations
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To: Joel Fernandes <joelaf@google.com>
Cc: LKML <linux-kernel@vger.kernel.org>, Michal Hocko <mhocko@kernel.org>, Zhaoyang Huang <huangzhaoyang@gmail.com>, Ingo Molnar <mingo@kernel.org>, kernel-patch-test@lists.linaro.org, Andrew Morton <akpm@linux-foundation.org>, "open list:MEMORY MANAGEMENT" <linux-mm@kvack.org>, Vlastimil Babka <vbabka@suse.cz>

On Wed, 4 Apr 2018 09:03:47 -0700
Joel Fernandes <joelaf@google.com> wrote:


> > for the tests. Note, without this, I tried to allocate all memory
> > (bisecting it with allocations that failed and allocations that
> > succeeded), and couldn't trigger an OOM :-/  
> 
> I guess you need to have something *else* other than the write to
> buffer_size_kb doing the GFP_KERNEL allocations but unfortunately gets
> OOM killed?

Yeah, for some reason, my test box seems to always have something doing
that, because I trigger an OOM about 2 out of every 3 tries.

Here's the tasks that trigger it:

 lvmetad, crond, systemd-journal, abrt-dump-journ, chronyd,

I guess my system is rather busy even when idle :-/

> 
> Also, I agree with the new patch and its nice idea to do that.

Thanks, want to give it a test too?

-- Steve