Add shallow clone to hg
Issue #203 closed
Git and darcs offer a shallow clone option (--depth 1 for git and --lazy for darcs). Hg can accomplish a similar thing by running hg clone -r tip URL. This should be implemented following the same rules as shallow clones for git and darcs.
Shallow cloning is a performance improvement only. I would wait with implementing this until we have experience in parallel checkouts, which can conceivably improve speed by an order of magnitude.
Speed is not the only advantage of shallow clones. Smaller repository size is also something worth to consider.
I was actually incorrect about this. I misread the documentation of hg; -r tip will actually perform a full clone. It seems hg does not currently support shallow clones, but they are looking into it.
On another note, the parallel checkout (using -p) has been quite stable for me lately, and it does significantly reduce checkout/update times. I am considering making parallel mode the default if the user's Perl supports threads, or at least letting users decide how many threads to use (currently -p is locked at 4 threads).
I would advertise the feature first, and wait for a few months' worth of bug reports, before making this the default.