Thanks for the timings. Alas, I'm leaving in the morning for vacation, so I'm not sure when I'll have time to profile these operations. And I'm still puzzling over how to speed up darcs get (i.e. the long discussion of http pipelining, which will not, of course, do anything to help the poor folks stuck with ssh...). The 100x slower pull is indeed a bit puzzling. I can't help but wonder if it's the hash-checking (but that seems very unlikely)... David On Mon, Dec 17, 2007 at 12:29:20PM +0000, Simon Marlow wrote:
Continuing my performance tests, I tried unpulling and re-pulling a bunch of patches in a GHC tree. I'm unpulling about 400 patches using --from-tag, and then pulling them again from a local repo. Summary: darcs2 is about 10x slower than darcs1 on unpull, and on pull it is 100x slower in user time but only 20x slower in elapsed time.
In both cases, the repository was on an NFS filesystem. In the darcs2 case, the repository I was pulling from was on the local disk, and I'm also using a cache (NFS-mounted). The darcs2 repository has been optimized, but the darcs1 repository has not (at lesat, not recently). I did all of these a couple of times to eliminate the effects of cache preloading etc., the times reported are from the second run.
------- darcs 1:
$ time darcs unpull --from-tag 2007-09-25 -a Finished unpulling. 35.17s real 5.77s user 1.00s system 19% darcs unpull --from-tag 2007-09-25 -a
$ time darcs pull ~/ghc-HEAD -a Pulling from "/home/simonmar/ghc-HEAD"... 33.51s real 3.62s user 1.05s system 13% darcs pull ~/ghc-HEAD -a
------- darcs 2:
$ time darcs2 unpull --from-tag 2007-09-25 -a Finished unpulling. 385.22s real 52.18s user 12.62s system 16% darcs2 unpull --from-tag 2007-09-25 -a
$ time darcs2 pull /64playpen/simonmar/ghc-darcs2 -a Finished pulling and applying. 668.75s real 290.74s user 15.03s system 45% darcs2 pull /64playpen/simonmar/ghc-darcs2 -a
-- David Roundy Department of Physics Oregon State University