From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: hosting git on a nfs
Date: Fri, 14 Nov 2008 12:14:23 -0800
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Cc: Brandon Casey <casey@nrlssc.navy.mil>,
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To: Linus Torvalds <torvalds@linux-foundation.org>
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In-Reply-To: <alpine.LFD.2.00.0811141109580.3468@nehalem.linux-foundation.org> (Linus
 Torvalds's message of "Fri, 14 Nov 2008 11:23:01 -0800 (PST)")
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Linus Torvalds <torvalds@linux-foundation.org> writes:

> I also think the thread cost was wrong: it did
>
> 	threads = index->cache_nr / 100;
>
> to give a first-order "how many threads do we want", but the thread 
> startup is likely to be higher than 100 lstat calls, so we probably want 
> fewer threads than that. It doesn't much matter for something like the 
> Linux kernel, where there are so many files that we'll end up maxing out 
> the threads anyway, but for smaller projects, I suspect a thread cost of 
> "one thread per 500 files" is more reasonable. You almost certainly don't 
> want to thread anything at all for fewer than a few hundred files.

If you have 1000 files in a single directory, do you still want 2 threads
following the "1/500" rule, or they would compete reading the same
directory and using a single thread is better off?