I have an check that I run before I run performance tests which sends a ping along all of the paths that I run perf testing on. It runs `ping -q -c 1 -s 1472 -M do <dest>` from every source to every destination running an iperf server It passes. I've set the MTU on all our network devices to
Just for kicks, I lowered the MTU on one of my sources and reran iperf as you suggested. The result was still very low. root@lab1r1u05:~# iperf -c 10.224.12.20 ------------------------------------------------------------ Client connecting to 10.224.12.20, TCP port 5001 TCP window size: 85.0 KByte (default) ------------------------------------------------------------ [ 3] local 10.224.12.10 port 34524 connected with 10.224.12.20 port 5001 [ ID] Interval Transfer Bandwidth [ 3] 0.0-11.0 sec 2.75 MBytes 2.10 Mbits/sec Carl On Tue, Jul 31, 2018 at 1:07 PM Guru Shetty <g...@ovn.org> wrote: > MTU? Big drops in performance numbers are usually because of packet > fragmentation. Keep the MTU of your packet origin to, say 1450 and retry? > > On 31 July 2018 at 12:01, Carl Baldwin <c...@ecbaldwin.net> wrote: > >> My apologies. I failed to include the ovs version number that I'm using. >> It >> is 2.7.3. Is there anything else I could check that maybe I'm not thinking >> of? >> >> Carl >> >> On Tue, Jul 31, 2018 at 11:01 AM Ben Pfaff <b...@ovn.org> wrote: >> >> > On Mon, Jul 30, 2018 at 02:02:16PM -0600, Carl Baldwin wrote: >> > > I recently tried pushing MPLS labels using OVS in a lab. >> > > >> > > Before adding MPLS push to the mix, I had four hosts: two pairs, each >> > > connected to a different set of TOR switches running VRRP. OVS (using >> > > kernel datapath) had a flow to write the VRRP mac address and output >> to a >> > > bond port. The bond is a Linux LACP bond, not an OVS bond. In this >> > > scenario, the TORs would route the packets through a default route our >> > > gateway routers to egress from the DC. This did fine and I was able to >> > push >> > > something around 42 Gbps using16 iperf2 TCP streams. >> > > >> > > ovs-ofctl add-flow -OOpenFlow13 br0 "table=25, ip, >> > > actions=output=${bond_port}" >> > > >> > > My next step was to push an MPLS label onto the packet. The above flow >> > > became this: >> > > >> > > ovs-ofctl add-flow -OOpenFlow13 br0 "table=25, ip, >> > > >> > >> actions=push_mpls:0x8847,set_field:1048001->mpls_label,output=${bond_port}" >> > > >> > > 1048001 is a static label that I configure on the TORs which sends the >> > > packet up to the same gateway using MPLS instead of IP routing. So, >> the >> > > packets would take the same path out of the network but using an MPLS >> > path. >> > > With this change, things worked well from a functional perspective but >> > the >> > > performance fell drastically to around 30-40 Mbps. >> > > >> > > I'm pretty confident in the network fabric because I tried the same >> > > scenario using LInux MPLS and it performed well. From the network >> > fabric's >> > > point of view, it was exactly the same (static label through LACP >> bond to >> > > VRRP mac). >> > > >> > > I found in the faq [1] under "Does Open vSwitch support MPLS?" that >> "Open >> > > vSwitch version 2.4 can match, push, or pop up to 3 MPLS labels and >> look >> > > past the MPLS label into the encapsulated packet. It will have kernel >> > > support for MPLS, yielding improved performance." I looked through the >> > git >> > > history and I don't see much evidence of this actually getting done >> for >> > the >> > > 2.4 release. Is this faq accurate? >> > >> > It looks like MPLS datapath support was fairly solid by OVS 2.6, at any >> > rate. If your kernel module is older than that, I'd recommend >> > upgrading. >> > >> _______________________________________________ >> dev mailing list >> d...@openvswitch.org >> https://mail.openvswitch.org/mailman/listinfo/ovs-dev >> > > _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev