On 04/10/2017 11:50 AM, Jarod Wilson wrote:
On 2017-04-08 7:33 PM, Jarod Wilson wrote:
I'm digging into some bug reports covering performance issues with balance-rr,
and discovered something even worse than the reporter. My test setup has a pair
of NICs, one e1000e, one e1000 (but dual e1000e seems the same). When I do a
test run in LNST with bonding mode balance-rr and either miimon or arpmon, the
throughput of the UDP_STREAM netperf test is absolutely horrible:
TCP: 941.19 +-0.88 mbits/sec
UDP: 45.42 +-4.59 mbits/sec
I figured I'd try LNST's packet capture mode, so exact same test, add the -p
flag and I get:
TCP: 941.21 +-0.82 mbits/sec
UDP: 961.54 +-0.01 mbits/sec
Uh. What? So yeah. I can't capture the traffic in the bad case, but I guess
that gives some potential insight into what's not happening correctly in either
the bonding driver or the NIC drivers... More digging forthcoming, but first I
have a flooded basement to deal with, so if in the interim, anyone has some
insight, I'd be happy to hear it. :)
Okay, ignore the bit about bonding, I should have eliminated the bond from the
picture entirely. I think the traffic simply ended up on the e1000 on the
non-capture test and on the e1000e for the capture test, as those numbers match
perfectly with straight NIC to NIC testing, no bond involved. That said, really
odd that the e1000 is so severely crippled for UDP, while TCP is still
respectable. Not sure if I have a flaky NIC or what...
For reference, e1000 to e1000e netperf:
TCP_STREAM: Measured rate was 849.95 +-1.32 mbits/sec
UDP_STREAM: Measured rate was 44.73 +-5.73 mbits/sec
Maybe check that you have re-ordering issues? I ran into that with igb
recently and it took a while to realize my problem!
Thanks,
Ben
--
Ben Greear <gree...@candelatech.com>
Candela Technologies Inc http://www.candelatech.com
