From: Julian Phillips <julian@quantumfyre.co.uk>
Date: Tue, 17 Apr 2007 22:03:14 GMT
Subject: Re: [PATCH] refs.c: add a function to sort a ref list, rather then sorting on add
Message-ID: <Pine.LNX.4.64.0704172300170.16435@beast.quantumfyre.co.uk>
In-Reply-To: <Pine.LNX.4.64.0704171350000.5473@woody.linux-foundation.org>

On Tue, 17 Apr 2007, Linus Torvalds wrote:

>
>
> On Tue, 17 Apr 2007, Julian Phillips wrote:
>>
>> It's the tag auto-following code, I'm calling read_ref to see if I already
>> have that tag - and it appears that doing that a few thousand times takes a
>> while.
>
> Heh. I think we should probably call read_refs() just once to read them
> all (when most of them are packed, that's cheap), and then after that,
> have some way to just check for a match on the refs we have cached.

I had a look at the exclude_existing function in show-ref.  That uses 
for_each_ref to build a path_list, and path_list_has_path to do the 
filtering...

Using that I get (worst of 5, warm cache):
real    0m0.526s
user    0m0.302s
sys     0m0.176s

-- 
Julian

  ---
The descent to Hades is the same from every place.
 		-- Anaxagoras