From: Johan Herland <johan@herland.net>
Date: Thu, 19 Jun 2008 08:58:58 GMT
Subject: Re: What's cooking in git.git (topics)
Message-ID: <200806191058.58074.johan@herland.net>
In-Reply-To: <7v3anb19n7.fsf@gitster.siamese.dyndns.org>

On Wednesday 18 June 2008, Junio C Hamano wrote:
> [New Topics]
>
> * jh/clone-packed-refs (Sun Jun 15 16:06:16 2008 +0200) 4 commits
>  - Teach "git clone" to pack refs
>  - Prepare testsuite for a "git clone" that packs refs
>  - Move pack_refs() and friends into libgit
>  - Incorporate fetched packs in future object traversal
>
> Would be helpful cloning from a repository with insanely large number of
> refs.

The first 3 patches (i.e. the bottom 3 in the above list) might be 
considered general cleanup patches, and are independent of each other (i.e. 
you might want to include them on their own merit, independently of patch 
#4).

The final patch doesn't make any difference for "regular" repos (e.g. 
git.git with ~200 refs) on Linux (see below). But once the number of refs 
increase, the difference becomes obvious.

Here are some numbers to give some more context:

All tests done on 64-bit quad-core Linux, cloning locally (hard-linked):

~200 refs (git.git):
current next:    0.2s
w/above patches: 0.2s

~1000 refs (test repo):
current next:    0.16s
w/above patches: 0.05s

~11000 refs (test repo):
current next:    1.3s
w/above patches: 0.3s

~26000 refs (actual repo at $dayjob):
current next:    3.2s
w/above patches: 0.8s


Regards,

...Johan

-- 
Johan Herland, <johan@herland.net>
www.herland.net