if_bridge turns off checksum offload of members?

Greetings,

I just noticed, that when I add em network card to bridge the checksum offload is turned off.
I even put in my rc.conf:
ifconfig_em0="rxcsum up"
ifconfig_em1="rxcsum up"
but after reboot both em0 and em1 have this feature disabled.

Is this expected behavior? Should I care about csum in bridge mode?
I noticed that enabling checksum offload manually improve things little btw.

Also I'm experimenting with bridge performance and with today's 7-stable I can't reach
the results from my previous test with 7-current (before few months)

The best that bridge can do today is just 720kpps (just incoming) vs 1000kpps with sources from few months ago.
I'm using the same hardware and same configuration so I'm not sure why -stable is slower.

--

Best Wishes,
Stefan Lambrev
ICQ# 24134177

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