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Date: Mon, 15 Dec 2003 16:42:59 -0500 (EST)
From: Garrett Wollman <wollman@khavrinen.lcs.mit.edu>
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To: Barry Bouwsma <freebsd-misuser@remove-NOSPAM-to-reply.NOSPAM.dyndns.dk>
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Subject: ENOBUFS and DNS...
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<<On Mon, 15 Dec 2003 22:17:53 +0100 (CET), Barry Bouwsma <freebsd-misuser@remove-NOSPAM-to-reply.NOSPAM.dyndns.dk> said:

> If I were to tweak the sysctl net.inet.ip.intr_queue_maxlen from its
> default of 50 up, would that possibly help named?

No, it will not have any effect on your problem.  The IP input queue
is only on receive, and your problem is on transmit.

The only thing that could possibly help your problem is increasing
your output queue length, and it is already quite substantial; doing
this will probably hurt as much as it helps, since the output queue is
serviced in strict FIFO order and there is no way to ``call back'' a
packet once it makes it there.  Something like ALTQ might help if you
are able to use a WFQ discipline and assign a high weight to DNS
traffic.

-GAWollman