On Tue, Feb 01, 2011 at 02:59:57PM -0800, Shirley Ma wrote: > On Tue, 2011-02-01 at 23:56 +0200, Michael S. Tsirkin wrote: > > There are flags for bytes, buffers and packets. > > Try playing with any one of them :) > > Just be sure to use v2. > > > > > > >I would like to change it to > > > half of the ring size instead for signaling. Is that OK? > > > > > > Shirley > > > > > > > > > > Sure that is why I made it a parameter so you can experiment. > > The initial test results shows that the CPUs utilization has been > reduced some, and BW has increased some with the default parameters, > like 1K message size BW goes from 2.5Gb/s about 2.8Gb/s, CPU utilization > down from 4x% to 38%, (Similar results from the patch I submitted a > while ago to reduce signaling on vhost) but far away from dropping > packet results. > > I am going to change the code to use 1/2 ring size to wake the netif > queue. > > Shirley
Just tweak the parameters with sysfs, you do not have to edit the code: echo 64 > /sys/module/vhost_net/parameters/tx_bufs_coalesce Or in a similar way for tx_packets_coalesce (since we use indirect, packets will typically use 1 buffer each). -- MST -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html