kern.ipc.nmbclusters limit reached

[Ben Woods]

On Tuesday, June 30, 2015, Olivier Nicole <Olivier.Nicole at cs.ait.ac.th>
wrote:

> Hi,
>
> Since I updated my amanda server to 10.1, I cannot complete a back-up,
> the system will freeze in the middle of the dumps with bunches of error:
>
> Jun 30 09:37:16 amanda kernel: [zone: mbuf_cluster] kern.ipc.nmbclusters
> limit reached
>
>
> The kernel is:
>
> FreeBSD amanda.cs.ait.ac.th 10.1-RELEASE-p9 FreeBSD 10.1-RELEASE-p9 #0
> r282829: Wed May 13 14:31:30 ICT 2015     root at amanda.cs.ait.ac.th:/usr/obj/usr/src/sys/GENERIC
> amd64
>
> and
>
> sysctl kern.ipc.nmbclusters
> kern.ipc.nmbclusters: 253064
>
> This ipc.nmbcluster seems terribly high (like 0.5 GB memory), but that's
> the value set by the kernel by default!
>
> Something must be wrong there, but I don't know ehre to look.
>
> Thanks in advance for the help,
>
> olivier
> --
>

I guess you are using Intel igb(4) or em(4) network interface cards?

This is a known issue, and the work around proposed by the pfsense project
is to manually increased the nmbcluster limit:

Add the following to /boot/loader.conf:

kern.ipc.nmbclusters="1000000"



https://doc.pfsense.org/index.php/Tuning_and_Troubleshooting_Network_Cards#Intel_igb.284.29_and_em.284.29_Cards

Regards,
Ben


-- 

--
From: Benjamin Woods
woodsb02 at gmail.com