From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Rafael J. Wysocki" <rjw@sisk.pl>
Subject: Re: [PATCH 3/9] PM: suspend_block: Abort task freezing
	if a suspend_blocker is active.
Date: Tue, 12 May 2009 18:55:36 +0200
Message-ID: <200905121855.37585.rjw@sisk.pl>
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To: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <ncunningham@crca.org.au>, u.luckas@road.de, swetland@google.com, linux-pm@lists.linux-foundation.org
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On Tuesday 12 May 2009, Pavel Machek wrote:
> On Sat 2009-05-09 01:01:01, Rafael J. Wysocki wrote:
> > On Saturday 09 May 2009, Nigel Cunningham wrote:
> > > Hi.
> > > 
> > > On Fri, 2009-05-08 at 16:40 +0200, Rafael J. Wysocki wrote:
> > > > The timeout is actually a workaround for the problem that we don't
> > > > really
> > > > know if tasks are going to react to our freeze requests and how much time it is
> > > > going to take.  The current value of 20 s was chosen after a number of
> > > > experiments showing that in some cases the freezing _was_ going to take so
> > > > much time.  Of course the question is whether it makes sense to give up earlier
> > > > even if tasks would eventually freeze, but that's a different issue.
> > > 
> > > What were the circumstances in which freezing could take 20s?
> > 
> > Compiling the kernel with "make -j<big number>" on a dual core system IIRC.
> 
> IIRC the number happened because I saw up to 5sec under some heavy
> overload, and added some "safety margin".

No, it appeared after a number of experiments I carried out a couple of years
ago. :-)

Best,
Rafael