On 2015/1/29 21:00, Xie, Huawei wrote: > > >> -----Original Message----- >> From: Linhaifeng [mailto:haifeng.lin at huawei.com] >> Sent: Thursday, January 29, 2015 8:39 PM >> To: Xie, Huawei; dev at dpdk.org >> Subject: Re: [dpdk-dev] [PATCH] vhost: notify guest to fill buffer when >> there is >> no buffer >> >> >> >> On 2015/1/29 18:39, Xie, Huawei wrote: >> >>>> - if (count == 0) >>>> + /* If there is no buffers we should notify guest to fill. >>>> + * This is need when guest use virtio_net driver(not pmd). >>>> + */ >>>> + if (count == 0) { >>>> + if (!(vq->avail->flags & >>>> VRING_AVAIL_F_NO_INTERRUPT)) >>>> + eventfd_write((int)vq->kickfd, 1); >>>> return 0; >>>> + } >>> >>> Haifeng: >>> Is it the root cause and is it protocol required? >>> Could you give a detailed description for that scenario? >>> >> >> I use mz to send data from one VM1 to VM2.The two VM use virtio-net driver. >> VM1 execute follow script: >> for((i=0;i<999999999;i++)); >> do >> mz eth0 -t udp -A 1.1.1.1 -B 1.1.1.2 -a 00:00:00:00:00:01 -b >> 00:00:00:00:00:02 -c >> 10000000 -p 512 >> sleep 4 >> done >> >> VM2 execute follow command to watch: >> watch -d ifconfig >> >> After many hours VM2 stop to receive data. >> >> Could you test it ? > > > We could try next week after I send the whole patch. > How many hours? Is it reproducible at your side? I inject packets through > packet generator to guest for more than ten hours, haven't met issues.
About three hours. What kind of driver you used in guest?virtio-net-pmd or virtio-net? > As I said in another mail sent to you, could you dump the status of vring if > you still have the spot? How to dump the status of vring in guest? > Could you please also reply to that mail? > Which mail? > For the patch, if we have no root cause, I prefer not to apply it, so that we > don't send more interrupts than needed to guest to affect performance. I found that if we add this notify the performance is better(growth of 100kpps when use 64byte UDP packets) > People could temporarily apply this patch as a work around. > > Or anyone > OK.I'm also not sure about this bug.I think i should do something to found the real reason. > >> -- >> Regards, >> Haifeng > > > -- Regards, Haifeng
