From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: Performance issue of 'git branch'
Date: Wed, 22 Jul 2009 22:13:33 -0700
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Cc: "Carlos R. Mafra" <crmafra2@gmail.com>,
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 (Linus Torvalds's message of "Wed\, 22 Jul 2009 21\:10\:49 -0700 \(PDT\)")
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Linus Torvalds <torvalds@linux-foundation.org> writes:

> On Wed, 22 Jul 2009, Linus Torvalds wrote:
>> 
>> But I'll see if I can dig up my non-binary-search patch and see if I can 
>> make it go faster. My machine is fast, but not so fast that I can't 
>> measure it ;)
>
> Oh. We actually merged a fixed version of it. I'd completely forgotten.

As the commit message of 628522e (sha1-lookup: more memory efficient
search in sorted list of SHA-1, 2007-12-29) shows, it didn't get any great
performance improvements, even though it did make the probing quite a lot
less memory intensive.

Perhaps you can spot obvious inefficiency in the code that I failed to
see, just like you recently did for "show --cc" codepath?