On Tue, Jul 01, 2014 at 04:24:23PM -0700, Howard Tsai wrote: > I would like to prioritize in-band controller and manager (OVSDB) traffic > (on linux.) The goal is to guarantee that these traffic goes out first, > without rate-limiting other traffic. > > I noticed that controller traffic goes out with dscp=48. However, since > Linux do not understand dscp, the traffic is still considered "normal > service" (instead of Minimize-Delay.) It seems to me that setting > SO_PRIORITY to TC_PRIO_INTERACTIVE (defined in > ~linux/include/uapi/linux/pkt_sched.h) in lib/socket-util.c:set_dscp (after > setting IP_TOS) could solve this.
That sounds reasonable. Will you send a patch? > Manager traffic seems to do dscp only if remote management is enabled by > "ovs-vsctl set-manager ptcp:6640". If the remote manager is added by > "ovs-appctl -t ovsdb-server ovsdb-server/add-remote ptcp:6640" (without any > other remotes), the traffic is not dscp marked. It seems to be a bug to > me. Also, is one way preferable to the other to add a remote? It's not a bug, it just means that "ovsdb-server/add-remote" doesn't provide a DSCP option. That's because it's only intended for adding local controllers (e.g. "unix:", "punix:"). If you want to set other features, you can add a manager through ovs-vsctl. > The Linux socket priority issue also happens to tunnel traffic (setting tos > in dscp language is not effective.) I suppose another option would be > needed. > > I understand prioritization can also be done with a few tc/iptables rules. > I just hope that the out-of-the-box defaults are in fact effective. I think the intent is that you should configure your system to interpret DSCP appropriately, but I don't know for sure. _______________________________________________ discuss mailing list discuss@openvswitch.org http://openvswitch.org/mailman/listinfo/discuss
