Re: Emacs repository benchmark: bzr and git (rerun)

[James Westby]

On Wed, 2008-03-19 at 13:37 +0200, Teemu Likonen wrote:
> Hey! I realised that the emacs bzr repository was not fully optimized 
> with "bzr pack" command. By running this command it really improves the 
> performance of bzr; now I'm getting similar numbers as some of you. I 
> really apologise for the misleading information I have spread. I want 
> to correct my mistakes by running my tests again (see below).
> 
> This raises questions though. I had downloaded the premade emacs bzr 
> repo from <http://bzr.notengoamigos.org/> and it seems to have its repo 
> pretty much optimized since it performs much better than my previous 
> benchmark. I had done almost nothing with the repository after that, 
> just some bzr-pulls and performance tests. How come the emacs bzr 
> repository slows down so much and so quickly? My experience is that you 
> definitely want to run "bzr pack" quite often.

Hi,

Thanks for updating us.

I wanted to point out that bzr automatically repacks on commit
every so often, this means that the performance degredation should
be bounded, but yes, you will often be able to speed it up by
running "pack" manually.

In recent versions (I don't know which exactly, sorry) git has
also added the auto-repack on commit. I don't know how their
strategy differs from bzr's, but they should both ensure that
it never gets really bad.

I do think the effects of repacking bzr are very drastic, so it
is probably worth investigating where the slowdown was.

Do you still have your .bzr/repository/ from the old tests?
Is there anything in .bzr/repository/obsolete_packs/ ? That would
let us know just how many packs you were running with.

Thanks,

James