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: Sun, 18 Mar 2007 02:45:12 -0700
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Cc: Nicolas Pitre <nico@cam.org>,
	Morten Welinder <mwelinder@gmail.com>,
	Git Mailing List <git@vger.kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
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	(Linus Torvalds's message of "Sat, 17 Mar 2007 20:06:24 -0700 (PDT)")
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Linus Torvalds <torvalds@linux-foundation.org> writes:

> This shaves off another ~5-10% from some loads that are very tree 
> intensive (notably doing commit filtering by a pathspec).
>
> Signed-off-by: Linus Torvalds  <torvalds@linux-foundation.org>"

With your 256-entry cache, Nico's reusing objects out of delta
base cache, and this strlen() patch

	git blame -C block/ll_rw_blk.c

gets these numbers:

(v1.5.0)
14.71user 0.26system 0:15.07elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+93622minor)pagefaults 0swaps

(master + three patches)
8.94user 0.14system 0:09.10elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+40075minor)pagefaults 0swaps

Just for fun, these are the same for the kernel history with tglx-history 
repository's history grafted behind it, i.e. with this grafts file:

$ cat .git/info/grafts
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 e7e173af42dbf37b1d946f9ee00219cb3b2bea6a

(v1.5.0)
73.80user 2.57system 1:16.40elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+773077minor)pagefaults 0swaps

(master + three patches)
65.14user 0.40system 1:05.55elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+125052minor)pagefaults 0swaps

In either case, it is showing drastic reduction of minor faults.