Re: Partitioned packs

On Tue, 3 Apr 2007, Chris Lee wrote:

Date: Tue, 3 Apr 2007 18:36:44 -0700
From: Chris Lee <redacted>
To: git@vger.kernel.org
Subject: Partitioned packs

I've been running some experiments, as hinted earlier by the
discussion about just how much git-index-pack sucks (which, really,
isn't much since the gaping memleak is gone now).

These experiments include trying to see if there's a noticeable
performance improvement by splitting out objects of different types
into different packs. So far, it definitely seems to make a
difference, though not the one I was initially expecting. For all of
these tests, I did 'sysctl -w vm.drop_caches=3' before running, to
effectively simulate a cold-cache run.

I wonder what order the packs ended up in. if git had to go through the wrong 
pack completely first before finding the pack that it needed, that coudl account 
for extra time.

is it worth makeing up single packs that order the three different types of 
object differently within the one pack to see what difference it makes to have 
to walk past all the blobs to get to the commits and trees?

David Lang