Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   valdis.kletnieks@vt.edu
To:     Jan Kara <jack@suse.cz>
cc:     Pavel Machek <pavel@ucw.cz>,
        Mel Gorman <mgorman@techsingularity.net>,
        kernel list <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@osdl.org>, vbabka@suse.cz,
        aarcange@redhat.com, rientjes@google.com, mhocko@kernel.org,
        zi.yan@cs.rutgers.edu, hannes@cmpxchg.org
Subject: Re: [regression -next0117] What is kcompactd and why is he eating 100% of my cpu?
In-reply-to: <20190128091627.GA27972@quack2.suse.cz>
References: <20190126200005.GB27513@amd> <12171.1548557813@turing-police.cc.vt.edu> <20190127141556.GB9565@techsingularity.net> <20190127160027.GA9340@amd> <13417.1548624994@turing-police.cc.vt.edu>
 <20190128091627.GA27972@quack2.suse.cz>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Date:   Tue, 29 Jan 2019 20:06:39 -0500
Message-ID: <14875.1548810399@turing-police.cc.vt.edu>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Mon, 28 Jan 2019 10:16:27 +0100, Jan Kara said:

> So my buffer_migrate_page_norefs() is certainly buggy in its current
> incarnation (as a result block device page cache is not migratable at all).
> I've sent Andrew a patch over week ago but so far it got ignored. The patch
> is attached, can you give it a try whether it changes something for you?
> Thanks!

Been running with the patch for about 24 hours, haven't seen kcompactd
misbehave.  I even fired up a Chrome with a lot of tabs open, a Firefox, and a
kernel build, intentionally drove the system into swapping, and kcompactd
didn't make it into the top 10 on 'top'.

I'm willing to say put a "tested-by:" on that one,  it looks fixed from here.
If there's any remaining bugs, they're ones I can't seem to trigger...