[dpdk-users] KNI Very Slow

[Cliff Burdick]

Hi, I've been playing around with the sample KNI app, and for some reason
it's extremely slow to respond to pings after the application starts. I'm
starting it with:

 ./build/kni -c 0xf0 -n 4 -- -p 0x3 -P --config="(0,4,6),(1,5,7)"

and after it starts up, I'm able to ifconfig vEth0 with an IP without
issues. However, when I start to ping from another machine, it takes about
45 seconds of continuous pings before anything comes back. I added a couple
printfs to the kni app after rte_kni_tx_burst is called, and
after rte_kni_rx_burst. When each ping arrives, I see rte_kni_tx_burst
sending the packets to Linux. However, the printf after rte_kni_rx_burst
has a long period of time where nothing is coming out. Only after the 45
seconds does it reach some kind of "steady state" where the pings work
continuously, and the kni tx/rx are happening immediately. Has anyone seen
this behavior?