Chelsio T520-SO-CR low performance (netmap tested) for RX

[Marcus Cenzatti]

hello,

I am testing a chelsio t520-so-cr connected to a Intel card with ix(4) driver, I can get the ncxl0 interface to transmit at 14Mpps to another chelsio or to a Intel card. However I can only get 800Kpps-1Mpps for RX tests from both chelsio or Intel.

I have test with both FreeBSD 11 and FreeBSD 10.3-PRERELEASE.

I tested it untuned first and later I have applied tuning recommendations I found on BSDRP[1] website. Results still ranging from 800Kpps to 1Mpps for RX.

Tests are done w/ with pkt-gen in netmap mode on ncxl interface with both IP address and MAC address source/dest.

I have tested ix-ix and I can confirm 14Mpps for both RX and TX directions. I have tested with two different chelsio T520 and both have the very same results.

What particular loader/sysctl or ifconfig options I should investigate?

I also tested disabling txcsum, rxcsum and TSO. Results are different but still on the much lower mentioned 800K-1M pps rate.

thank you

[1]http://bsdrp.net/documentation/examples/forwarding_performance_lab_of_a_hp_proliant_dl360p_gen8_with_10-gigabit_with_10-gigabit_chelsio_t540-cr