[darcs-users] darcs patch: add exception to haskell_policy.sh for D... (and 61 more)

David Roundy droundy at darcs.net
Thu Oct 30 17:17:47 UTC 2008

On Wed, Oct 29, 2008 at 07:50:32PM +0000, Eric Kow wrote:
> On Wed, Oct 29, 2008 at 10:30:12 -0700, Jason Dagit wrote:
> > I want to see benchmarks too, but I thought I would justify why we
> > expect this to be no slower than the previous code...Everything below
> > is stuff that we discussed during the Sprint.
> Well, attached is a second set of comparative timing tests, sorry, only
> run once and with no nice output yet.  Hopefully you can use a graphical
> diff tool to do side by side comparison.
> A nice little summariser script, maybe using the Haskell tabular
> library might be handy

Unless you've named them wrong, it looks like salvo-9b has on the an effect
of slowing darcs down, when it has any significant effect.  That doesn't
sound like a good optimization...  It'd also be good to test against
pre-salvo-8 with or without bytestring.

I don't strongly object to requiring bytestring, but given that we *know*
that it's not as efficient as it could be by at least 10% or 20% (unless
this is a timings error or a misnamed-files issue), it does seem worth
tracking down what went wrong while we've still got two similar versions of
darcs to test against.  I'll run some quick tests on my computer to see how
things look here.  Could you try doing a darcs check test? Darcs check
isn't a common operation, but it's commonly a slow operation, so it's a
pretty good canary for telling when certain operations are slowed down
(i.e. reading patches and applying them).  I notice that annotate is
particularly slow with the new bytestring, which suggests that perhaps
patch reading (either zlib interactions or maybe parsing) has been slowed
down disproportionately).


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