We recently got some results running Couchbase's key/value benchmark test with OpenOnload. Results are pretty wicked: Sub 20us for 99% centile SET and GET operations.
./memcachetest -h <server_ip>:8091 -L 5 -t [1|8|higher] -i <at_least_10k> -c <at_least_100k> -M <size of objects...range it from 512 to 16k> -F
Point the benchmark at the local Moxi port and away you go. Kernel is version 2.6.39.2, Membase is version 1.7.1.1 and OpenOnload is version 201104. Platform is 2x X5677 3.4 Ghz Westmere CPU / 6GB RAM. Here's the data:
As an aside, some of you might have seen the Facebook/Tilera paper on memcached performance. The absolute numbers we're hitting with Onload are soooo much better it isn't even funny.