On Thu, Jul 12, 2018 at 01:21:03PM +0800, Jason Wang wrote: > > > On 2018年07月12日 11:34, Michael S. Tsirkin wrote: > > On Thu, Jul 12, 2018 at 11:26:12AM +0800, Jason Wang wrote: > > > > > > On 2018年07月11日 19:59, Michael S. Tsirkin wrote: > > > > On Wed, Jul 11, 2018 at 01:12:59PM +0800, Jason Wang wrote: > > > > > On 2018年07月11日 11:49, Tonghao Zhang wrote: > > > > > > On Wed, Jul 11, 2018 at 10:56 AM Jason Wang <jasowang@xxxxxxxxxx> wrote: > > > > > > > On 2018年07月04日 12:31, xiangxia.m.yue@xxxxxxxxx wrote: > > > > > > > > From: Tonghao Zhang <xiangxia.m.yue@xxxxxxxxx> > > > > > > > > > > > > > > > > This patches improve the guest receive and transmit performance. > > > > > > > > On the handle_tx side, we poll the sock receive queue at the same time. > > > > > > > > handle_rx do that in the same way. > > > > > > > > > > > > > > > > For more performance report, see patch 4. > > > > > > > > > > > > > > > > v4 -> v5: > > > > > > > > fix some issues > > > > > > > > > > > > > > > > v3 -> v4: > > > > > > > > fix some issues > > > > > > > > > > > > > > > > v2 -> v3: > > > > > > > > This patches are splited from previous big patch: > > > > > > > > http://patchwork.ozlabs.org/patch/934673/ > > > > > > > > > > > > > > > > Tonghao Zhang (4): > > > > > > > > vhost: lock the vqs one by one > > > > > > > > net: vhost: replace magic number of lock annotation > > > > > > > > net: vhost: factor out busy polling logic to vhost_net_busy_poll() > > > > > > > > net: vhost: add rx busy polling in tx path > > > > > > > > > > > > > > > > drivers/vhost/net.c | 108 ++++++++++++++++++++++++++++---------------------- > > > > > > > > drivers/vhost/vhost.c | 24 ++++------- > > > > > > > > 2 files changed, 67 insertions(+), 65 deletions(-) > > > > > > > > > > > > > > > Hi, any progress on the new version? > > > > > > > > > > > > > > I plan to send a new series of packed virtqueue support of vhost. If you > > > > > > > plan to send it soon, I can wait. Otherwise, I will send my series. > > > > > > I rebase the codes. and find there is no improvement anymore, the > > > > > > patches of makita may solve the problem. jason you may send your > > > > > > patches, and I will do some research on busypoll. > > > > > I see. Maybe you can try some bi-directional traffic. > > > > > > > > > > Btw, lots of optimizations could be done for busy polling. E.g integrating > > > > > with host NAPI busy polling or a 100% busy polling vhost_net. You're welcome > > > > > to work or propose new ideas. > > > > > > > > > > Thanks > > > > It seems clear we do need adaptive polling. > > > Yes. > > > > > > > The difficulty with NAPI > > > > polling is it can't access guest memory easily. But maybe > > > > get_user_pages on the polled memory+NAPI polling can work. > > > You mean something like zerocopy? Looks like we can do busy polling without > > > it. I mean something like https://patchwork.kernel.org/patch/8707511/. > > > > > > Thanks > > How does this patch work? vhost_vq_avail_empty can sleep, > > you are calling it within an rcu read side critical section. > > Ok, I get your meaning. I have patches to access vring through > get_user_pages + vmap() which should help here. (And it increase PPS about > 10%-20%). Remember you must mark it as dirty on unpin too ... > > > > That's not the only problem btw, another one is that the > > CPU time spent polling isn't accounted with the VM. > > > Yes, but it's not the 'issue' of this patch. Yes it is. polling within thread context accounts CPU correctly. > And I believe cgroup can help? > > Thanks cgroups are what's broken by polling in irq context. > > > > > > > > > Thanks _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
