Hi I am checking performance DPDK VIRTIO mode running on KVM (Linux ubuntu 3.11.0-15-generic). The maximum throughput I reached was 4Gbps and then I saw an interesting phenomena. Every ~2min traffic stopped completely and then immediately came back. This happened in a periodic fashion. I have never seen such thing in a pass-through mode, where I reached very much higher rates of course. Can you please help in resolving this problem in VIRTIO ? Thank you Yan
On Sun, Oct 12, 2014 at 12:37:37PM +0000, Yan Freedland wrote:
> Every ~2min traffic stopped completely and then immediately came back. This
> happened in a periodic fashion.
To me it sounds like it could be similar to what I've seen when I ran out of
mbuf's or ran out of RX / TX descriptor entries. It could be worth checking
the error counters on the interfaces with DPDK and Linux OS / ethtool to see
what might be incrementing during the failed time periods.
Matthew.
Hi , > -----Original Message----- > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Matthew Hall > Sent: Sunday, October 12, 2014 9:18 PM > To: Yan Freedland > Cc: dev@dpdk.org > Subject: Re: [dpdk-dev] DPDK - VIRTIO performance problems > > On Sun, Oct 12, 2014 at 12:37:37PM +0000, Yan Freedland wrote: > > Every ~2min traffic stopped completely and then immediately came back. > > This happened in a periodic fashion. > > To me it sounds like it could be similar to what I've seen when I ran out of > mbuf's or ran out of RX / TX descriptor entries. It could be worth checking the > error counters on the interfaces with DPDK and Linux OS / ethtool to see > what might be incrementing during the failed time periods. > I didn't meet this issue before, I am not sure if the following patch will fix this issue or not. Please try it. http://dpdk.org/dev/patchwork/patch/779/ By the way, what kind of backend did you use? User space vhost, or other backend? Thanks Changchun
Hi I found that what blocked me was actually the "nf_conntrack", So enlarging the maximum there solved the issue. Thanks Yan -----Original Message----- From: Ouyang, Changchun [mailto:changchun.ouyang@intel.com] Sent: Monday, October 13, 2014 6:10 AM To: Matthew Hall; Yan Freedland Cc: dev@dpdk.org; Ouyang, Changchun Subject: RE: [dpdk-dev] DPDK - VIRTIO performance problems Hi , > -----Original Message----- > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Matthew Hall > Sent: Sunday, October 12, 2014 9:18 PM > To: Yan Freedland > Cc: dev@dpdk.org > Subject: Re: [dpdk-dev] DPDK - VIRTIO performance problems > > On Sun, Oct 12, 2014 at 12:37:37PM +0000, Yan Freedland wrote: > > Every ~2min traffic stopped completely and then immediately came back. > > This happened in a periodic fashion. > > To me it sounds like it could be similar to what I've seen when I ran > out of mbuf's or ran out of RX / TX descriptor entries. It could be > worth checking the error counters on the interfaces with DPDK and > Linux OS / ethtool to see what might be incrementing during the failed time periods. > I didn't meet this issue before, I am not sure if the following patch will fix this issue or not. Please try it. http://dpdk.org/dev/patchwork/patch/779/ By the way, what kind of backend did you use? User space vhost, or other backend? Thanks Changchun