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From Cliff Woolley <>
Subject Re: [PATCH] convert worker MPM to leader/followers design
Date Thu, 11 Apr 2002 23:28:37 GMT
On Thu, 11 Apr 2002, Aaron Bannert wrote:

>  Under typical conditions, long-running and short-running requests will
>  be distributed throughout the children. In order for this scenario to
>  occur, all M threads in a child would have to be in use by a long-lived
>  connection. Assuming a random distribution of these clients, I don't
>  see how this scenario can consistently occur except when all threads
>  across all children are already being occupied by long-lived connections.

Another thing of note is that this sort of problem will only happen (or
rather, will only be severe) when the server goes instantaneously from x
concurrent connections on average to x+y concurrent connections, where y
is large, which is what's happening when you suddenly ab pound a server,
because p_i_s_m doesn't have a chance to keep up.  Under production
circumstances, the number of concurrent connections would tend to have
less significant discontinuities.


   Cliff Woolley
   Charlottesville, VA

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