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Date: Tue, 25 Dec 2012 12:40:12 +0600
From: Tsaregorodtsev Denis <telemat@extrim.it>
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To: Ryan Stone <rysto32@gmail.com>
Subject: Re: 'no buffer space available' after switch goes down on freeBSD 7.3
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On 25.12.2012 07:01, Ryan Stone wrote:
>
> I don't believe that this is fixed in later versions of the driver. 
> The problem is that when the interface loses link the transmit queue 
> can fill up. Once that happens the driver never gets any more calls 
> from the network stack to make it send packets. Pinging the interface 
> fixes it because the driver processes rx.and tx from the same context, 
> so when it receives a packet it starts transmitting again.
>
> The patch that I sent fixes the problem by forcing the driver to 
> process the tx queue when ever links goes from down to up.
>
but on my production machine, when i see 'no buffer space available', 
pinging the interface does not fixes it. Last time I tried to ping, ssh 
to the machine, but machine stayed unavailable. Only `/etc/rc.d/netif 
restart` from local console helped.
I will try to reproduce the situation on test machine. if this happens, 
I will try the patch.
Thanks