kern.ipc.nmbclusters limit reached

[Olivier Nicole]

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
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