[ECOS] high bandwidth network problems

[ECOS] high bandwidth network problems

[Carl van Schaik]

Hi

I have my board connected to our backbone which has a huge ammount of
broadcast traffic continously (nearly 2000 machines), after a while, ecos
starts spewing out messages: and stops responding to network traffic.

warning: eth_recv out of MBUFs
setsoftnet

Can anyone tell me what the setsoftnet is supposed to do? Do I have to 
implement somthing in the network driver? What can I do to
prevent this from occuring?

thanks

Carl van Schaik   <carl@leg.uct.ac.za>
-----------------------------------------------------
Dept. Electrical Engineering, UCT

621 Menzies Building
University of Cape Town
Rondebosch   
Western Cape
7700
South Africa

Tel: +27 21 650-3467
Fax: +27 21 650-3465

RE: [ECOS] high bandwidth network problems

[Gary Thomas]

On 06-Sep-2000 Carl van Schaik wrote:
> Hi
> 
> I have my board connected to our backbone which has a huge ammount of
> broadcast traffic continously (nearly 2000 machines), after a while, ecos
> starts spewing out messages: and stops responding to network traffic.
> 
> warning: eth_recv out of MBUFs
> setsoftnet
> 
> Can anyone tell me what the setsoftnet is supposed to do? Do I have to 
> implement somthing in the network driver? What can I do to
> prevent this from occuring?
> 

Try increasing the number of mbufs.  Set the configuration parameter
CYGPKG_NET_MEM_USAGE to something larger (the default is 256*1024).

Do you have the latest code from CVS?  I seem to recall something in there
about an mbuf memory leak which was fixed recently.  This might help.

Re: [ECOS] high bandwidth network problems

[Andrew Lunn]

> Try increasing the number of mbufs.  Set the configuration parameter
> CYGPKG_NET_MEM_USAGE to something larger (the default is 256*1024).
> 
> Do you have the latest code from CVS?  I seem to recall something in there
> about an mbuf memory leak which was fixed recently.  This might help.

Increasing the memory is not the real solution. The code will cope
with running out of mbufs, its a normal occurance. Whats wrong is
printing these messages. Printing these messages is a classic denial
of service problem. What it should do is limit the number of times it
prints it, to a maximum of one per second, or even not at all.

        Andrew

Re: [ECOS] high bandwidth network problems

[Gary Thomas]

On 06-Sep-2000 Andrew Lunn wrote:
>> Try increasing the number of mbufs.  Set the configuration parameter
>> CYGPKG_NET_MEM_USAGE to something larger (the default is 256*1024).
>> 
>> Do you have the latest code from CVS?  I seem to recall something in there
>> about an mbuf memory leak which was fixed recently.  This might help.
> 
> Increasing the memory is not the real solution. The code will cope
> with running out of mbufs, its a normal occurance. Whats wrong is
> printing these messages. Printing these messages is a classic denial
> of service problem. What it should do is limit the number of times it
> prints it, to a maximum of one per second, or even not at all.
> 

A reasonable observation.  The messages are[were] there simply so we 
could see if the code was detecting such conditions and doing the right
thing.  If they messages themselves are getting in the way, just nuke 'em.