Info Q article on DVCS - a request and some feedback

[Jelmer Vernooij]

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Ian Clatworthy wrote:
> AUVRAY Sebastien wrote:
>> Hi Ian,
>>
>> With: /cd mozilla.bzr bzr clone master my-fix/ I get better
>> times: 117sec, which is nearly twice faster than without shared
>> repository but still a lot higher than competitors.
>
> OK. Could you please update your graph (and supporting data) in
> your article accordingly?
>
> Given the slowness you're seeing vs my earlier benchmarks, I'm
> guessing we're slowing down badly in this case as history grows.
> This may well be because we validate everything as we create a new
> branch. In Bazaar, clone is more than just "copy" - it also
> prevents any corruptions in the source being propagated.
>
> While we don't openly document it, you can always use 'cp -a' to
> clone a Bazaar branch inside a shared repository. Because of our
> storage architecture (where the revisions are stored in the shared
> repo), this is space efficient (without the need for hardlinking).
>
> Anyhow, thanks for the updated measurement. I'll raise a bug about
> this issue.
I wonder if we should have a "benchmark mode", i.e. some flag you can
set to say "I want performance, not  correctness" that would turn off
some of this checking. git and mercurial seem to prefer performance in
most cases and allow extra options for extra correctness (checking).
I.e. you can check the repository manually after it's been copied with
git/mercurial. Another example I ran into a while ago:
http://jelmer.vernstok.nl/blog/archives/216-Git-cutting-corners.html

Maybe --turbo? :-)

Cheers,

Jelmer
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