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From Brian Pane <>
Subject Re: [PATCH] convert worker MPM to leader/followers design
Date Thu, 11 Apr 2002 19:07:34 GMT
Bill Stoddard wrote:

>>Right, the problem is that the listener needs to avoid doing the
>>accept if the queue is full.
>>That part is easy: add a "block_if_queue_full()" method on the
>>fd_queue class, and have the listener call it before doing an
>I am not an expert on the worker MPM but I don't think that is an accurate statement of
>the problem.  The accept thread uses ap_queue_push() to enqueue a socket for the worker
>threads. ap_queue_push() will block if the queue is full.

You're right.  The logic really needs to be: don't do the accept unless
there is an idle thread.


>The problem is that the queue can be EMPTY even when all the worker threads are busy
>handling connections.  The way the code is today, the queue can hold ap_threads_per_child
>elements. Now consider 2 x ap_threads_per_child connections comming into the server at
>once.. The first 1 x ap_threads_per_child connections will be accepted and handled by
>worker threads. The next ap_threads_per_child connections will get queued and this is
>precisely the problem...

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