Deadly embrace between pthread_cond_wait and pthread_cond_signal

Robert Collins
Wed Jun 27 16:00:00 GMT 2001

----- Original Message -----
From: "Christopher Faylor" <>
> >>I bet it would improve even more if we replaced the VirtualQuery
> >>in, too.
> >
> >With Rob's new patch that does this,
> >there actually isn't very much difference
> >
> >real    7m10.729s
> >user    2m50.963s
> >sys     1m11.721s
> >
> >Thanks !
> Huh.  I wonder why it makes such a big difference for pthreads.

Volume of calls :}. openening files doesn't occur quite as often as (say)
locking a mutex.

I'd like to publicly thank Greg Smith for his excellent profiling work in
identifying the bottleneck here. I know how time consuming that can be :}.

Thanks Greg!


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