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Message-ID: <1474634362.4025.23.camel@gmail.com>
Subject: Re: [RFC][PATCH] dm: Remove dm_bufio_cond_resched()
From: Mike Galbraith <umgwanakikbuti@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
        Mikulas Patocka <mpatocka@redhat.com>,
        Mike Snitzer <snitzer@redhat.com>, Alasdair Kergon <agk@redhat.com>,
        Ingo Molnar <mingo@kernel.org>, linux-kernel@vger.kernel.org,
        dm-devel@redhat.com, Joe Thornber <ejt@redhat.com>
Date: Fri, 23 Sep 2016 14:39:22 +0200
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On Fri, 2016-09-23 at 14:26 +0200, Peter Zijlstra wrote:
> On Fri, Sep 23, 2016 at 02:17:10PM +0200, Mike Galbraith wrote:
> > On Fri, 2016-09-23 at 10:00 +0200, Thomas Gleixner wrote:
> > > On Fri, 23 Sep 2016, Peter Zijlstra wrote:
> > 
> > > > Is anybody still using PREEMPT_NONE? Most workloads also care
> > > > about
> > > > latency to some extend. Lots of code has explicit
> > > > cond_resched() and
> > > > doesn't worry.
> > > 
> > > Dunno. But I bet there are workloads which love it.
> > 
> > SUSE definitely uses it.  I had presumed that was enterprise
> > standard.
> 
> Hmm, I thought most distros defaulted to PREEMPT_VOLUNTARY.

I use PREEMPT_VOLUNTARY for my desktop, that offering much better
performance than the PREEMPT desktop targeted kernels (ick), but
workhorses run PREEMPT_NONE for maximum throughput.

	-Mike