em0 NIC slow on 8.2-p1 amd64?
Michael W. Lucas
mwlucas at blackhelicopters.org
Thu Jul 21 14:10:16 UTC 2011
On Wed, Jul 20, 2011 at 09:32:27PM +0200, Eduardo Morras wrote:
> At 21:16 20/07/2011, Michael W. Lucas wrote:
>
> >It's at gigabit:
> >
> >em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
> >
> >options=219b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,TSO4,WOL_MAGIC>
> > ether 00:15:17:31:c8:fe
> > inet xxxxxxx
> > media: Ethernet autoselect (1000baseT <full-duplex>)
> > status: active
>
> All seems to be ok, try a netstat -I em0 -d (it's a capital 'i') to
> get statistics. If too much packets are dropped recheck cables.
>
> Other options:
>
> a) 30 MB/s looks very strange, do you have pf or similar with a filter rule?
> b) Have you checked your disk i/o performance?
> c) If you generate the data dinamically, may be your producer app is
> the problem.
>
> About the em specific problem under 8.2 you cite, others can guide
> better than me.
>
> HTH
No obvious errors on netstat:
netstat -I em0 -d
Name Mtu Network Address Ipkts Ierrs Idrop Opkts Oerrs Coll Drop
em0 1500 <Link#1> 00:15:17:31:c8:fe 11709782 0 0 6855755 0 0 0
em0 1500 139.171.199.0 data5-vm 9546994 - - 7584135 - - -
PF is running, but disabling it makes no difference in throughput.
Disk is mostly idle... not saying it can't be disk, mind you, but
local disk-to-disk copies go much more quickly. I'm testing by copying
an ISO.
And as far as me knowing "many more things," well, if I knew what the
problem was, I wouldn't be begging for help like any other user. :-)
Thanks,
==ml
--
Michael W. Lucas
http://www.MichaelWLucas.com/, http://blather.MichaelWLucas.com/
Latest book: Network Flow Analysis http://www.networkflowanalysis.com/
mwlucas at BlackHelicopters.org, Twitter @mwlauthor
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