[darcs-users] darcs patch: refactor Slurpy to common up name compon... (and 9 more)

[David Roundy]

On Sun, Nov 02, 2008 at 10:39:07PM +0000, Ganesh Sittampalam wrote:
> On Sun, 2 Nov 2008, David Roundy wrote:
> >On Thu, Oct 30, 2008 at 09:31:31PM +0000, Ganesh Sittampalam wrote:
> >>On Wed, 29 Oct 2008, Ganesh Sittampalam wrote:
> >>
> >>>OK, I've now benchmarked this work on the GHC repo in kowey's
> >>>zoo, and the overall picture suggests significant speedups (20% or
> >>>so) on most of the tests (get, pull, unpull, record, unrecord,
> >>>revert), with possible slowdowns in whatsnew and get-lazy of
> >>>about 10%.
> >>
> >>My apologies for lazy benchmarking. This is all complete rubbish, as I
> >>should have realised if I stopped to think about what was getting faster
> >>and whether it was plausible.
> >>
> >>After some more careful runs thanks to kowey's scripts, the basic
> >>conclusion is that there isn't any obvious (>5%) difference in performance
> >>either way, although in general the new code is probably a bit faster than
> >>the old code.
> >
> >Do you still think this code is worth putting in? I lean against it, if it
> >has no measurable performance impact.  On the other hand, using a map does
> >seem like a good idea, so if you think this should go in, I'll go ahead and
> >review it.
> 
> Sorry, I was unclear. It still has a huge impact on 'whatnew -sl' on the 
> articifial repo with 1000 new files that I've been testing with (quadratic 
> -> something a lot better, probably n log n). It's just the testing on 
> "normal" repos like ghc etc that shows no noticeable difference; which is 
> at it should be really, I was benchmarking to ensure there was no slowdown 
> there, and got carried away by results showing a speedup across the board 
> without really thinking about them.
> 
> So I do think this should go in.

Ah, okay, that's good to hear.  It did seem like they should be an
improvement... do you have any suggestions for a possible subportion that
would be worth reviewing separately, as this looks a bit daunting to finish
this evening?
-- 
David Roundy
http://www.darcs.net