[darcs-users] Darcs 2.4 - performance testing (stage 0)

Max Battcher me at worldmaker.net
Wed Jan 13 03:52:17 UTC 2010

On 1/12/2010 22:10, Jason Dagit wrote:
>     Obviously the darcs-stats file is in pretty high demand and
>     darcs-benchmark doesn't seem to be waiting long enough between runs
>     to close the file correctly (or otherwise doesn't have the proper
>     sharing permissions setup for the file).
> The haskell run-time created it for the duration that darcs is executing
> and I bet darcs tried to access while it was running.  I think there are
> essentially two solutions:
> 1) Create the file elsewhere
> 2) make it a non-fatal error

It's not a fatal error for the benchmark, it keeps on going. I think 
that is directly and indirectly related to the later issues (such as the 
second one I posted). darcs-benchmark probably needs some sort of: 
"failed with error? then sleep a few seconds and retry".

It's not in the repository, its in darcs-benchmark's "_playground" 
parent directory. The error is from the haskell run-time, even it looks 
like it might be darcs reporting it (what my earlier snippet didn't show 
is that its followed immediately by GHC dumping its RTS options help 

It seems that GHC itself is fighting for access rights to that file. I'm 
not sure if its worth reporting as a GHC bug, but it the easy solution 
is probably some sort of "cooldown" in darcs-benchmark between darcs 
calls to help insure that GHC has relinquished that file between 

>     Well, that's also interesting because it couldn't find darcs-2.3.1
>     in its place in Haskell's bin directory (despite accessibility in
>     PATH), but it found this other Bin directory in my PATH.
> Is it possible that the order of your paths is interfering?

Well, now that I think of it, one is in my account PATH (which works 
from darcs-benchmark) and one in the system-wide PATH (which apparently 
doesn't work).

>     Anyway, it doesn't look like darcs-benchmark wants to run correctly
>     on Windows Vista just yet.
> I'm still troubleshooting the OS X case too.  Thanks for trying to
> figure this out!

Interestingly enough, I gave it some time to get further in the process 
and it seems to hit the same "hanging" issue that you've seen, appearing 
to just fall asleep upon hitting the second big get test.

It would probably be helpful if darcs-benchmark run --verbose would 
pass-through darcs' progress reports.

--Max Battcher--

More information about the darcs-users mailing list