Bazaar on the slow track -- history notes

Posted Sep 12, 2012 5:06 UTC (Wed) by abentley (guest, #22064)
In reply to: Bazaar on the slow track -- history notes by martin.langhoff
Parent article: Bazaar on the slow track

Bazaar-NG was never a fork of Tom Lord's TLA. That fork was Baz, which was called "Bazaar" at the time. Bazaar-NG was always a from-scratch design intended to support lossless imports from Baz.

I don't think Martin considered Bazaar-NG's storage unreliable. Bazaar-NG was self-hosting in March after 3 months of development, and Martin wouldn't have done that if he didn't trust it. His original web site warned "This is pre-release unstable code. Keep backups of any important information.", but I think this was just an overabundance of caution.

One of the reasons Bazaar(-NG) didn't switch to git's core was because git didn't provide a library. And even if it had, it would have been in C, not Python. But we also wanted something that worked with our data model. We felt we could do at least as well as git in storing data, and I've never had reason to doubt the 2a format's efficiency.

Bazaar on the slow track -- history notes

Posted Sep 13, 2012 1:51 UTC (Thu) by martin.langhoff (subscriber, #61417) [Link] (2 responses)

My memory was fuzzy in the baz/bazaarNG distinction. Thanks for clarifying.

On whether the reliability of storage and Martin Pool's regard of it... I have an anecdote :-)

I was sitting at Martin Pool's presentation in linux.conf.au 2006 (Dunedin, NZ). From the back of the room, in the QA part of the session, someone asked: "so, is it ready for real work? You see, I have this large codebase that's been developed for 25+ years. After several VCS migrations, it's in CVS with a messy repo due to migrations. We are a widely distributed team, and we are hurting. Should I be migrating to bzr now?"

Martin looked rather uncomfortable with the question, and muttered something like "not really, not yet". He had already been less than reassuring when I had asked whether Bazaar storage was delta-centric (darcs-like) or snapshot centric (git-like).

The "is it ready for real workdd?" question had come from Jim Gettys, who I did not know personally at the time. After the talk I asked him whether he had been talking about X.org and whether he could give me access to those messy X.org CVS repos. I would try importing them into git, and we could see if he liked the outcome.

It was the start of a long hard road -- it led to many improvements to git- cvsimport, yet the migration was done with parsecvs (written by Keith Packard).

I was at linux.conf.au to run a workshop on git; Linus joined us, so it stretched from 2 to 4hs. We had a much smaller room assigned than Bazaar, but you could feel we were rocking and rolling :-) I believe Matt Mackall was there too, talking about Mercurial, but I missed it.

This happened long ago -- and this is how I remember it. Quotes are as best as I can recall.

In my view, 2006/2007 was the time where the overall trends in the DVCS space got established; x.org migrated to git, Mozilla ran high profile bakeoffs between DVCSs, etc. And at that time Bazaar was on unfortunately on unsure footing (bad timing!). As a result, Git and Mercurial generally stole the show...

Bazaar on the slow track -- history notes

Posted Sep 13, 2012 7:34 UTC (Thu) by mbp (subscriber, #2737) [Link] (1 responses)

I think my discomfort would have been about performance for the size of the tree and history they were talking about, not about reliability. bzr was not ready for big trees in 2006 that time.

bzr has always had snapshot storage and never been darcs-like.

I reject, and resent, the implication that I publicly advocated something I privately didn't think was reliable.

Bazaar on the slow track -- history notes

Posted Sep 13, 2012 13:50 UTC (Thu) by martin.langhoff (subscriber, #61417) [Link]

My apologies. I did not mean to cause offense. Time has its way of distorting memories, perhaps you or others have a different recollection?

My impression after your talk back then was that perhaps Bazaar-NG was performing or planning internal storage changes (or something like that) and that at that particular time those were awkward questions. Not that you did not trust or promote Bazaar, but that you were stating "not right now".