linux-kernel - Re: thousands of kworker processes with 4.7.x and 4.8-rc*

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Date:   Sun, 25 Sep 2016 20:22:29 +0200
From:   Mike Galbraith <umgwanakikbuti@...il.com>
To:     Tomasz Chmielewski <mangoo@...g.org>
Cc:     LKML <linux-kernel@...r.kernel.org>
Subject: Re: thousands of kworker processes with 4.7.x and 4.8-rc*

On Sun, 2016-09-25 at 19:21 +0200, Mike Galbraith wrote:
> On Sun, 2016-09-25 at 21:40 +0900, Tomasz Chmielewski wrote:
> 
> > The problem is the allocator.
> > 
> > -CONFIG_SLUB=y
> > +CONFIG_SLAB=y
> > 
> > 
> > With SLUB, I'm getting a handful of kworker processes, as expected.
> > 
> > With SLAB, I'm getting thousands of kworker processes.
> > 
> > 
> > Not sure if that's expected behaviour or not.
> 
> I seriously doubt 1500+ kworkers piling up is expected.
> 
> 4.7.0-rc4       47
> 4.7.0-rc5       1592
> 
> Presuming you didn't switch to SLAB and/or change userspace all around
> while testing, that would still indicate a kernel regression lurking
> between rc4 and rc5.

Nevermind, seems config change was how you met the thing.

FWIW, I turned on SLAB with a distro config here, and see no such
behavior.  If I could reproduce, I'd take the busted config back to
older kernels.

	-Mike