Sunay, I'm in a strange situation. I modified my driver code to use only mac_rx() and didn't export any Rx rings. Now the stack doesn't respond on getting ping request from remote. snoop on SUT shows all packets received from remote but it doesn't show any response to remote.
Am I missing something ? Thanks, ~Reang. On Sat, Oct 24, 2009 at 3:14 AM, Sunay Tripathi <Sunay.Tripathi at sun.com>wrote: > You can read the code :) But seriously, if polling was not buying us > anything, why would we have done it. The typical mac_rx path means that > packets are processed in a interrupt only context and if a CPU can keep > up, then you should be OK. Its totally dependent on packets per second > rate. So even on 1 Gb NIC, with smaller packets, todays CPUs can't keep > up. This is where polling along with packet chaining makes a big > difference. Read the Sigcomm papers we have to understand why we need > it (they are on crossbow opensolaris docs page). Thats just the > performance side. Then you add the virtualization side where packets > for a VM need to be isolated from otehr VMs and processed on the > correct CPU etc etc and again by exposing rings to MAC is allowing > polling to kick in is how we control things. > > To make long story short, if you are writing a driver which is not > dealing with high performance or going to be deployed in virtualized > scenarios etc, then you don't need to expose Rx rings and can just > use the mac_rx interface. > > HTH, > Sunay > > > Reang Su wrote: > >> >> Ok, Is there any other way from driver writer's perspective to disable it? >> What will happen if I only use mac_rx() instead of mac_rx_ring() ? >> Please shed some light on its difference? >> Thanks a lot. >> ~Reang. >> On Fri, Oct 23, 2009 at 10:34 PM, Sunay Tripathi <Sunay.Tripathi at >> sun.com<mailto: >> Sunay.Tripathi at sun.com>> wrote: >> >> It depends on the NIC. If you are using anything other than nxge, just >> create a VNIC (don't plumb it) and polling on primary NIC will get >> disabled. This is a bug that is being fixed but right now the >> easiest way. >> >> Cheers, >> Sunay >> >> Reang Su wrote: >> >> I'm trying to check performance with and without dynamic >> poll(legacy) feature in OpenSolaris. >> >> Can anybody know what could be the easiest way ? >> >> regards, >> ~Surjit. >> >> On Fri, Oct 23, 2009 at 8:01 PM, Gireesh Nagabhushana >> <dngireesh at gmail.com <mailto:dngireesh at gmail.com> >> <mailto:dngireesh at gmail.com <mailto:dngireesh at gmail.com>>> >> wrote: >> >> Why do you want to disable it? >> >> -- Gireesh >> >> >> On Fri, 2009-10-23 at 18:00 +0530, Reang Su wrote: >> > Hi, >> > >> > Anybody has tried disabling MAC_CAPAB_RINGS feature. >> > Is this a must feature to have in our driver for >> OpenSolaris stack to >> > work? Or we can still live without this ? >> > >> > regards, >> > ~Reang. >> > _______________________________________________ >> > driver-discuss mailing list >> > driver-discuss at opensolaris.org >> <mailto:driver-discuss at opensolaris.org> >> <mailto:driver-discuss at opensolaris.org >> <mailto:driver-discuss at opensolaris.org>> >> >> > http://mail.opensolaris.org/mailman/listinfo/driver-discuss >> >> >> >> >> ------------------------------------------------------------------------ >> >> _______________________________________________ >> crossbow-discuss mailing list >> crossbow-discuss at opensolaris.org >> <mailto:crossbow-discuss at opensolaris.org> >> >> http://mail.opensolaris.org/mailman/listinfo/crossbow-discuss >> >> >> >> -- Sunay Tripathi >> Distinguished Engineer >> Solaris Core Operating System >> Sun MicroSystems Inc. >> >> Solaris Networking: >> http://www.opensolaris.org/os/community/networking >> Project Crossbow: http://www.opensolaris.org/os/project/crossbow >> >> >> >> > > -- > Sunay Tripathi > Distinguished Engineer > Solaris Core Operating System > Sun MicroSystems Inc. > > Solaris Networking: http://www.opensolaris.org/os/community/networking > Project Crossbow: http://www.opensolaris.org/os/project/crossbow > > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.opensolaris.org/pipermail/crossbow-discuss/attachments/20091026/391c26e1/attachment.html>
