>> Hi Vasim, Jerin, >> >> Overall looks good and I not getting any functional error but I am observing >> a >> huge performance drop with this update, 3.8Mpps to 0.7Mpps [1]. > > Hi Ferruh, > When it comes to actual kernel netdev test cases like iperf or any other use > cases, there would not be any impact on performance. I think synthetic test > case like loopback mode might not be the actual test case alone to depend on > when the kernel module is featured to work with kind of devices(pdev or > vdev). Users can always fallback to pa mode with cmd line option. > > Please suggest your thoughts on considering what test case to use & evaluate > the performance difference.
Hi Vasim, I also assume the real life test cases will be affected less, but the loopback performance testing is good to show performance impact of the change. (Stephen's predictions that KNI is not as fast as tun/tap are getting more real by time J) At least I think the possible performance drop and how to mitigate it should be documented both in release notes and kni documentation. For the final decision, I am not objecting it but I would like to see more ack from community to confirm that we trade off iova=va functionality against performance. @Jerin, @Thomas, should we conclude this in techboard? Perhaps we can get it for rc2 and drop it back if rejected in techboard? Regards, ferruh
