Problems with jumbo frames on nfe

Pascal Braun pascal.braun at
Tue May 19 13:14:42 UTC 2009

Pyun YongHyeon wrote:
> On Tue, May 19, 2009 at 11:31:02AM +0200, Pascal Braun wrote:
>> Hi,
>> I'm currently testing jumbo frames on a Sunfire 4540 running with 
>> FreeBSD 8-Current (build on April 8th). While using the nfe driver I'm 
>> having some unexpected problems if i try to bring up the interface with 
>> MTU sizes greater than 1970 bytes.
>> The error message (in dmesg) is:
>> nfe2: initialization failed: no memory for rx buffers
> It means you've run out of jumbo clusters. Check the output of
> "netstat -m" and see how many jumbo cluster requests were denied.

771/1149/1920 mbufs in use (current/cache/total)
770/680/1450/25600 mbuf clusters in use (current/cache/total/max)
770/510 mbuf+clusters out of packet secondary zone in use (current/cache)
0/9/9/12800 4k (page size) jumbo clusters in use (current/cache/total/max)
0/0/0/16384 9k jumbo clusters in use (current/cache/total/max)
0/0/0/3200 16k jumbo clusters in use (current/cache/total/max)
1732K/1683K/3416K bytes allocated to network (current/cache/total)
0/0/0 requests for mbufs denied (mbufs/clusters/mbuf+clusters)
0/0/0 requests for jumbo clusters denied (4k/9k/16k)
0/0/0 sfbufs in use (current/peak/max)
0 requests for sfbufs denied
0 requests for sfbufs delayed
0 requests for I/O initiated by sendfile
0 calls to protocol drain routines

There are no denied requests. MTU size was about 1800.
But I have to add, that i cant even get the interface up if the mtu size 
is above 1970.

>> Does anyone have any ideas how to get jumbo frames working?
> How about increasing 9K jumbo clusters(kern.ipc.nmbjumbo9) with
> sysctl(8)?

sunfire# sysctl -a | grep jumbo
kern.ipc.nmbjumbo16: 3200
kern.ipc.nmbjumbo9: 16384
kern.ipc.nmbjumbop: 12800

I increased kern.ipc.nmbjumbo9 to 16384 (was 6400) but that didn't seem 
to help. Do you have another idea?


More information about the freebsd-current mailing list