Networking: Still waiting for mbuf cluster
Thomas.Doerfler at imd-systems.de
Fri Oct 24 07:43:40 UTC 2003
the RTEMS networking stack produces this message, when it ran
out of mbuf clusters. During startup, the stack allocates a
certain amount of memory as mbufs. You can increase that
amount with the 4. and 5. parameter of the
"rtems_bsdnet_config" data structure.
But I guess that this will only delay your problem. Maybe your
application does not free the received mbufs after it has
processed them? Or you have another mbuf leak in your system.
> My RTEMS application communicates with a Linux-PC via connectionless UDP
> receiving and replying UDP packets every ~20 milliseconds.
> After a few minutes the application stops communicating.
> The application is still running, but no more UDP packets are received.
> From time to time a message is displayed at the console:
> "Still waiting for mbuf cluster."
> With [ethereal] I see that correct UDP packets are coming from the PC.
> Additionally the PC is sending ARP requests:
> "Who has 192.168.0.100 ? Tell 192.168.0.1"
> which are also not answered by RTEMS.
> What does this mean ?
> How can the UDP communication be restarted ?
> Any suggestions are highly appreciated.
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email: Thomas.Doerfler at imd-systems.de
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