No buffer space available

[Nikolay Pavlov]

On Monday, 23 April 2007 at  4:06:10 -0700, Jeremy Chadwick wrote:
> On Sat, Apr 07, 2007 at 08:20:58PM -0300, Marc G. Fournier wrote:
> > - --On Saturday, April 07, 2007 20:12:00 +0100 Chris <chrcoluk at gmail.com> wrote:
> > > Also to add I now have a 2nd box using 6.2 STABLE few days old code,
> > > had to use it because of broadcom 5755 nic card, I plan to use large
> > > tcp window sizes so will be interesting to see if this also suffers
> > > from the problem.
> > 
> > I've got 8 servers on the same network, 3 are almost identical, but one of them 
> > (the one with the problem) is using software RAID vs hardware ... but, if you 
> > are seeing it without using software RAID, then that is obviously not the 
> > culprit :(
> 
> May be a red herring...
> 
> I'm able to reproduce the "No buffer space available" message when
> setting net.inet.tcp.(send|recv)space to non-default values.  All I've
> tried is the following, with a kernel dated 2007/04/22:
> 
>   # sysctl net.inet.tcp.sendspace=131072
>   # sysctl net.inet.tcp.recvspace=262144
> 
> Example session:
> 
> $ su2
> # sysctl net.inet.tcp.sendspace=131072
> net.inet.tcp.sendspace: 32768 -> 131072
> # sysctl net.inet.tcp.recvspace=262144
> net.inet.tcp.recvspace: 65536 -> 262144
> # logout
> $ ssh medusa
> socket: No buffer space available
> ssh: connect to host medusa port 22: No buffer space available
> $ su2
> # sysctl net.inet.tcp.sendspace=32768
> net.inet.tcp.sendspace: 131072 -> 32768
> # sysctl net.inet.tcp.recvspace=65536
> net.inet.tcp.recvspace: 262144 -> 65536
> # logout
> $ ssh medusa
> Last login: Mon Apr 23 03:45:45 2007 from ...
> 
> I assume this is because the maximum size of a TCP datagram is 65536
> bytes, but as I'm not familiar enough with TCP on such a low level,
> this may be speculation on my part.
> 
> Just something worth checking/tinkering with.
> 

Try to adjust kern.ipc.maxsockbuf value.

-- 
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- Best regards, Nikolay Pavlov. <<<-----------------------------------    
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