Hi there, We tested TX performance of Virtio PMD by DPDK l2fwd, but found even at 60KPPS (720B packet length) TX rate, there is 1/1000 packet dropping rate. The log shows "No free tx descriptors to transmit" in Virtio PMD. Increasing TX queues by modifying DPDK l2fwd can decreases packet dropping rate, but can't ensure no packet dropping unless retransmitting packets that can't be sent successfully. Oppositely, RX rate can be 600KPPS without packet dropping.
Test Env - Host CPU: 4 cores, 2127.770MHz - Host Memory: 8G - Host OS: Linux dw-2 3.13.0-24-generic #46-Ubuntu SMP Thu Apr 10 19:11:08 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux - Guest CPU: 4 cores, 2127.770MHz - Guest Memory: 4G - Guest OS: fedora20 Anybody here face the same problem? -Tianlin
