DPDK usage discussions
 help / color / mirror / Atom feed
* [dpdk-users] Possibly wrong RX statistics reported by virtio driver (TRex generator)
@ 2018-10-31  8:29 Nikos Anastopoulos
  2018-10-31 15:25 ` Stephen Hemminger
  0 siblings, 1 reply; 2+ messages in thread
From: Nikos Anastopoulos @ 2018-10-31  8:29 UTC (permalink / raw)
  To: users

Hi list,



The TRex traffic generator's folks recommended us to contact you for an issue that might relate to DPDK virtio driver (https://groups.google.com/forum/#!topic/trex-tgn/LxtTV7G43AE).



Specifically, our scenario involves running TRex inside a KVM instance with 2 vhost-user ports, which are connected in loopback mode via an OVS-DPDK (i.e. whatever sent through port1 goes to port2, and vice versa). We observe that the received traffic volume reported by TRex is much less than the transmitted (it is constantly 4B per packet), whereas:

1) the count of the received packets is the same

2) the contents of the received packets, as captured _inside_ the VM, are the same with the transmitted



Specifically, we experimented with different packet sizes being transmitted, i.e. 64B, 150B, 1000B, yet in the receive path the reported incoming volume corresponded constantly to 4B-per-packet, for all cases.



The TRex engineers suggested that it seems like an RX counters issues in virtio driver.



Experimental setup:

- TRex v2.45 (uses DPDK 17.11 AFAIK), within a QEMU v2.12

- on the host: OVS 2.10.0 with DPDK 17.11.3



Thanks,

Nikos





^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2018-10-31 15:25 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-10-31  8:29 [dpdk-users] Possibly wrong RX statistics reported by virtio driver (TRex generator) Nikos Anastopoulos
2018-10-31 15:25 ` Stephen Hemminger

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).