From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Sun, 30 Dec 2007 19:58:02 GMT
Subject: Re: [PATCH WIP] sha1-lookup: make selection of 'middle' less aggressive
Message-ID: <alpine.LFD.1.00.0712301150120.32517@woody.linux-foundation.org>
In-Reply-To: <7vtzm08l9w.fsf@gitster.siamese.dyndns.org>



On Sun, 30 Dec 2007, Junio C Hamano wrote:
> 
> With this patch, we actually see slight improvements in
> execution time as well.  In the same partial kde repository
> (3.0GB pack, 95MB idx; the numbers are from the same machine as
> before, best of 5 runs):

Ok, I tried this a year ago, and never got any real improvement. And mine 
was buggy. See

	http://marc.info/?l=git&m=117537594112450&w=2

and I decided it wasn't worth it. Yours looks much better, and seems to 
get a real performance improvement, so go for it, but I doubt that the 
actual object lookup is really ever the main issue. I've never seen it 
stand out in the real profiles, although if it is able to cut down on IO 
(and your minor fault numbers are promising!), it might be more important 
than I'd otherwise think.

		Linus