pf slows down the network

[Predrag Punosevac]

I am running 

backup1# uname -a
DragonFly backup1.int.autonlab.org 3.8-RELEASE DragonFly v3.8.1-RELEASE
#16: Mon Jun 16 21:36:15 PDT 2014
justin at pkgbox64.dragonflybsd.org:/usr/obj/build/home/justin/src/sys/X86_64_GENERIC
x86_64


After enabling PF network really slows down to the point that server is
unusable. ssh login hangs about a minute.  It looks very similar to this
thread

http://serverfault.com/questions/514046/pf-slows-traffic-extremely-down

and as a matter of fact I am using em driver. 

Has anybody else noticed this?

Predrag