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From: John Baldwin <jhb@freebsd.org>
To: "Justin T. Gibbs" <gibbs@scsiguy.com>
Subject: Re: libthr and main thread stack size
Date: Mon, 22 Sep 2014 15:18:54 -0400
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 (bigwig.baldwin.cx); Mon, 22 Sep 2014 15:22:03 -0400 (EDT)
Cc: Konstantin Belousov <kostikbel@gmail.com>,
 "Ivan A. Kosarev" <ivan@ivan-labs.com>, freebsd-current@freebsd.org,
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On Sunday, September 21, 2014 09:36:25 PM Justin T. Gibbs wrote:
> On Sep 20, 2014, at 11:06 AM, Konstantin Belousov <kostikbel@gmail.com> 
wrote:
> > On Fri, Sep 19, 2014 at 03:27:25PM -0400, John Baldwin wrote:
> >> I suspect it was done out of reasons of being overly conservative in
> >> interpreting RLIMIT_STACK. I think it is quite surprising behavior
> >> though and would rather we make your option the default and implement
> >> what the Open Group says above.
> > 
> > Ok, below is the patch.  I felt bad about adding yet another magic and
> > undocumented tunable to our libthr.  Since there seems to be no
> > alternative than a tunable to enforce old behaviour, I documented
> > the quirks I am aware of.
> 
> Why do we need to support the old behavior?  Any program that ran in the old
> model will run in the new.  In the unlikely event that someone was using
> the old scheme for administrative control, there are other mechanisms for
> this already available that we can point them to instead.

I agree with this.  In my experience the issue it has always been the opposite 
(people having issues with the main stack shrinking).

-- 
John Baldwin