Need for cleanup of idle winbindd child processes...

[Volker Lendecke]

On Fri, Apr 25, 2014 at 03:31:24PM +0000, Ravindra Channabasappa wrote:
> I had kept the cleanup interval high (3*60) and by that
> time load test was finishing and the child winbindd were
> cleaned up after the load test.
> When I decreased the cleanup interval to 5 seecs I could
> see the multiple problems. Child winbindd processes were
> exiting immediately after handling auth requests.
> In effect many processes were spawned and exited during
> the load test.
> 
> I have re worked the patch and attaching with this mail.
> Now cleanup handler is installed in the parent winbindd
> (winbind.c).
> The handler iterates through all domains, all the child
> processes for each domain, checks if the child queue is
> empty, then if empty send SIGTERM signal to child.
> 
> This I tested with 5 secs interval under load. It seems to
> work as expected. For reference I am attaching the debug
> output (pertaining to the handler only).

Ok, this looks better, thanks. The DEBUG(0 in the non-error
case should be set a bit higher though.

Just an idea: With this patch the queue_length check only
looks at one specific snapshot in time. Would it be
beneficial and doable with little effort to always save the
last response time from a winbind child and check if the
child has been idle for, say, 1/3 of the timeout time? This
way restarting a child that is just very briefly idle could
be avoided.

With best regards,

Volker Lendecke

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