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Subject: Re: TREE_SRCU slows hotplug by factor ~16
From: Mike Galbraith <efault@gmx.de>
To: paulmck@linux.vnet.ibm.com
Cc: LKML <linux-kernel@vger.kernel.org>
Date: Thu, 27 Apr 2017 05:43:59 +0200
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On Wed, 2017-04-26 at 20:12 +0200, Mike Galbraith wrote:
> On Wed, 2017-04-26 at 10:56 -0700, Paul E. McKenney wrote:
> 
> > > OK, I do need to do more work.  My current guess is that I should have
> > > set the default for srcutree.exp_holdoff to 25*1000 instead of 50*1000.
> > > But I am sure that further data will show me the error of my ways.  ;-)
> 
> I can give that a go tomorrow (too crispy now).

real    0m39.177s
user    0m0.225s
sys     0m5.344s

tadaaa  (tricorder noises... it's dead Jim)