em0 freezes on ZFS server

[Willem Jan Withagen]

On 26-2-2010 16:07, Daniel Braniss wrote:
>> On Fri, 26 Feb 2010 15:04:37 +0200 Daniel Braniss<danny at cs.huji.ac.il>
>> wrote about Re: em0 freezes on ZFS server :
>>
>> DB>  >  At least in my case I found out what is eating the buffers: nfsd
>> DB>  >  does! The buffers stop increasing as soon as I stop nfsd. However,
>> DB>  >  they start increasing as soon as I start nfsd again.
>> DB>  >  Are there any ideas how to fix this? Downgrading back to 7-stable is
>> DB>  >  not really an easy task as far as I know, and I need the server to
>> DB>  >  run without having to reboot it once for twice a day...
>>
>> DB>  I want to add some spices to this stew: :-)
>>
>> You're welcome. :-)
>>
>> DB>  Some few day later it hung, and it's now hanging every few days.
>> DB>  Most of the hangs are because there is no network, but the NIC is bce
>> DB>  not em! I doubled kern.ipc.nmbclusters and lets see what happens ...
>>
>> Do you have nfsd running and serving clients? If so, we should maybe
>> change the topic to something like "possible nfs mbuf leakage"...
>>
> it's only purpose in life is a nfs server.
> but I wouldn't exclude zfs from the equation yet.
> I have othere nfs servers, not doing zfs and I don't see this.
>
>> DB>  23066/6634/29700 mbufs in use (current/cache/total)
>>
>> My server is at 22k now, and the buffer number is still increasing every
>> few seconds...
>> Can you monitor your mbuf usage and report if it grows?
>>
> I am, and in the last 2hs. it grew by about 300, it does oscilate, i.e. it
> grows some, then
> it goes down, but it seems that the low always increases.
>
> when I have enough data i'll plot it.

Same here, from the odd samples I make.

If I don't run my compiles, but just let the server sit.
It just oscilates +- 500 mbufs.

Once I start compiling, mbufs starts growing. I'm now at 22K

Main network (NFS) traffic is than
	postfix writing Maildir
	dovecot - Maildir work

Next to that it is also Samba server, but that doesn't seem to matter that 
much.....

--WjW