If it works as advertised, Arch should be significantly better for
OpenACS use than SubVersion, due to Arch's direct support for
distributed development (rather like BitKeeper's).
This February 2003
Linux Kernel list thread on version control
had some interesting info. From that, it seems likely that Arch is
still, at least currently, noticeably inferior to BitKeeper.
E.g., Olivier Galibert said, "Hell, arch is still at the
update-before-commit level. I'd have hoped PRCS would have cured that
particular sickness in SCM design ages ago." which sounds interesting,
although I don't know what that means exactly. (But Tom Lord thinks
it mostly
meaningless drivel,
and explains why.)
And Linus Torvalds mentioned, "Give it up. BitKeeper is simply
superior to CVS/SVN, and will stay that way indefinitely since most
people don't seem to even understand _why_ it is superior."
It is not clear to me whether Arch's (assumed) inferiority to
BitKeeper is fundamental, or Simply a Matter of Programming. Lacking
any additional information, I would tentatively conlude the latter -
Arch can catch up (eventually even surpass?) BitKeeper - but that
doing so is probably hard.
Even so, that doesn't matter to OpenACS, as we've been
getting along ok with CVS, which is much, much more inferior
to BitKeeper than Arch could be! So if Arch is judged to be, useful,
currently a substantial improvement over CVS, well-designed, likely to
undergo regular further improvement and maintainence, and a better
choice for OpenACS than other competing Open Source revision control
tools, then OpenACS should use it.
Note that above I said competing Open Source tools. What
about closed source tools, like BitKeeper? The Linux kernel project
uses BitKeeper. The Linux kernel is an extreme case of
needing the best distributed version control system you can get, and
needing it right away. Linus obviously decided that this need was so
compelling and immediate that it overroad any concerns over
BitKeeper's non-open-source license. OpenACS is not in that
situation; we have no such extreme and overriding needs. Therefore it
should be easy and best to simply side-step all the huge acrimonious
licensing flamewars that the kernel folks have gone through, by simply
going with the best Open Source tool, and looking at closed-source
tools primarily only in order to better understand and evaluate the
open source ones.
Perforce? It's closed source of course, and I've never heard
any arguments on why it's better than BitKeeper. My guess is
it isn't, at all. If we were going to go with a closed source tool
(bad idea), I think it'd be hard to come up with any good reasons to
use anything other than what the Linux kernel folks already went with
- BitKeeper.
Tom Lord (original author of Arch) made some fairly insightful
criticisms of SubVersion
back in February 2003. Basically, he thinks the SubVersion project is
fundamentlly a failure, and is interested in understanding why and
how.
Roberto, I would be very interested in seeing your stuff on OpenACS
switching to Gnu Arch!
