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From Greg Ames <>
Subject Re: timeout queues in event mpm
Date Mon, 14 Nov 2011 17:00:34 GMT
On Mon, Nov 14, 2011 at 11:12 AM, Paul Querna <> wrote:

> The problem became that in trunk, we had to told the lock for the
> timeout queues while we were doing the pollset operation.   The
> pollset already had its own internal mutex too, for its own rings.  So
> we were double locking a piece of fairly high used code.

> In regards to reducing latency, I'm thinking about using the
> apr_pollset_wakeup API, which uses an internal pipe under the covers.

So it's a tradeoff: the cost of double locking vs. the cost of the extra
syscalls and extra context switch.  I will take a look at the double
locking in trunk.  It sure would be nice to have our cake and eat it too.


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