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Date: Tue, 7 Apr 2015 03:58:24 +1000 (EST)
From: Bruce Evans <brde@optusnet.com.au>
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To: Adrian Chadd <adrian@freebsd.org>
Subject: Re: svn commit: r281103 - head/sys/amd64/amd64
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On Mon, 6 Apr 2015, Adrian Chadd wrote:

> Hi Bruce,
>
> There's been a bunch of research into that field lately.
>
> Eg: http://daim.idi.ntnu.no/masteroppgaver/009/9231/masteroppgave.pdf
>
> The best part (imho)- the length of your USER environment string
> influencing code runtime costs. :)

I fix the latter in an FP benchmark by aligning the stack to a page
boundary, and further adjusting it by a magic amount of a few hundred.
This only works for microbenchmarks, since in general the stack pointer
is too variable for a single adjustment to keep it from hitting things.

Bruce