From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <junkio@cox.net>
Subject: Re: [PATCH 3/2] Avoid unnecessary strlen() calls
Date: Mon, 19 Mar 2007 22:44:08 -0700
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Cc: "Shawn O. Pearce" <spearce@spearce.org>,
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To: Linus Torvalds <torvalds@linux-foundation.org>
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	(Linus Torvalds's message of "Mon, 19 Mar 2007 21:11:08 -0700 (PDT)")
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Linus Torvalds <torvalds@linux-foundation.org> writes:

> Dscho's bigger patch probably helps more on an in-order architecture, and 
> should be equally good on a P4 (or Opteron). On Core 2, neither of the 
> patches seem to make a huge difference.

Because hoisting stable test outside loop is always better for
any architecture, I thought picking between Gitte and Gitney
patches is a no brainer, and I didn't bother to compare-bench,
but I got curious.

(plain)
7.89user 0.15system 0:08.08elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+41608minor)pagefaults 0swaps
7.93user 0.18system 0:08.14elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+41608minor)pagefaults 0swaps

(gitte -- separate function for slow path)
6.98user 0.18system 0:07.17elapsed 100%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+41606minor)pagefaults 0swaps
7.14user 0.12system 0:07.26elapsed 100%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+41607minor)pagefaults 0swaps

(gitney -- cheap test first before isspace)
7.23user 0.18system 0:07.42elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+41608minor)pagefaults 0swaps
7.32user 0.14system 0:07.48elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+41607minor)pagefaults 0swaps

So it does not seem to make much difference on Athlon 64x2 either.

Will apply the "stupid hashcmp() removal" and Dscho's patch and
call it a day.