David Roundy wrote: > On Thu, Feb 07, 2008 at 03:26:09PM +0000, Simon Marlow wrote: >> Incedentally, I'm doing a get on this repository right now, and darcs2 has >> been silent (no progress info at all) for a couple of minutes, even though >> I can see it downloading stuff... oh, now it says "Identifying repository". > > This is rather a tricky scenario: the hashed_inventory of this repository > takes 36s to download on my computer using wget. Our current assumption in > the progress-reporting code is that any given download will be fast, and > the result is that this particular operation is going to take a minimum of > 36 seconds with no change in progress output. As it turns out, we download > hashed_inventory twice when we only need download it once, so that slows > things down dramatically. > > I can easily get rid of one of these downloads (which is just checking the > format of the repository, something that can more easily be done with a > check of _darcs/format, which always exists for hashed and darcs-2 > repositories). I'd actually also like to cache the contents of > hashed_inventory, in a way that would enable us to guarantee that it's only > downloaded once, which is good both for efficiency and for atomicity (to > make sure we don't use two versions of the remote repository but assume > they're the same). > > I'm testing (and planning to push) a patch now that'll cut 36 seconds on > this get for me, by avoiding one download of hashed_inventory, but I don't > see how to avoid a 36s wait with no new progress report without very > dramatically rewriting our libwww/libcurl bindings.
Ok, sounds reasonable. But perhaps there should be a progress message before the download starts, something like "getting http://darcs.haskell.org/ghc-darcs2/_darcs/hashed_inventory...";? Cheers, Simon _______________________________________________ darcs-devel mailing list darcs-devel@darcs.net http://lists.osuosl.org/mailman/listinfo/darcs-devel
