pf deadly slow

[J David]

On Fri, Oct 4, 2013 at 6:20 PM, Daniel Ballenger <lpmusix at gmail.com> wrote:
> For what it's worth I'm running Freebsd 9.2-RELEASE on top of proxmox with
> the virtio network driver and don't have this issue (easily pushes over
> 100Mbps, doing over 60Mbps at the moment)

Have a look at your /var/log/kern.log, /var/log/messages, and
/var/log/syslog on the proxmox host.

If you enable TSO and PF on a FreeBSD KVM virtual machine with virtio
network drivers, PF will turn silently disable checksum offloading,
and the Linux side will complain about improper checksums with
complete kernel stack traces *on* *every* *packet*, to each file.
Your network throughput then becomes a function of your disk I/O
performance. :-/

The proxmox guys were going to patch out the log message, but even if
they have now done that, it only masks the problem, it doesn't solve
it.

It does sound like you may have this issue because before a local
kernel hack, we were also seeing about 100Mbps with TSO enabled.
Post-hack performance is approaching 700Mbps.  Not bad for a virtual
machine.