event: closing keepalive conn on activity

I've had two relatively recent and relatively painful investigations
come down to this closure of keepalive connections on activity when an
individual child process has no idle workers:

https://github.com/apache/httpd/blob/trunk/server/mpm/event/event.c#L2190

This is worse than a typical keepalive race because the closure is
really in response to the poll seeing the activity.

Does it warrant a WARNING level message? It is nice to at least get
the connection details into the log. Or an option to queue/block for a
worker?


-- 
Eric Covener
[email protected]