Message-ID: <487FD1D9.9020100@kernel.org>
Date: Thu, 17 Jul 2008 16:12:25 -0700
From: "H. Peter Anvin" <hpa@kernel.org>
Organization: Linux Kernel Organization, Inc.
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To: Denys Vlasenko <vda.linux@googlemail.com>
CC: Ingo Molnar <mingo@elte.hu>, x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86: do not grow initial process stack so much
References: <200807162332.37741.vda.linux@googlemail.com>
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Denys Vlasenko wrote:
> 
> I do not see, though, why this can be useful for x86. The pages
> are not mapped anyway, so accessing them still causes page faults.
> No speedup for, say, rapidly spawning processes which need ~60k
> of stack right away. They will still fault in kernel, right?
> 

They will fault in the kernel, but only to fill the page tables, so it 
would cut down on latency.

I do *NOT* believe we should make this an x86-only change.  If it should 
be architecture-dependent I'd rather find the architectures that do need it.

However, before changing this I really want to see some of the history 
about why it's that way in the first place.

	-hpa
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