As long as I can remember only IP_GRE_DEMUX should be set to module to allow outside third-party module to work flawlessly. First you need to recompile the kernel with new config following appropriate Centos guidelines, then you should download openvswitch distribution and build kmod-openvswitch rpm following the included readme file.
On Fri, Jan 10, 2014 at 5:09 AM, Li, Chen <chen...@intel.com> wrote: > Can you explain about "as a module" more? > And after recompile, what operations should I do ? > I'm confused about this and have no idea what should I do exactly. > > Currently, I just install openvswitch directly using command "yum install > openvswitch", and have no configuration to it. > > Thanks. > -chen > > > -----Original Message----- > From: Andrey Korolyov [mailto:and...@xdel.ru] > Sent: Friday, January 10, 2014 12:36 AM > To: Li, Chen > Cc: Zhou, Han; Chris Luke; 'Jesse Gross'; discuss@openvswitch.org > Subject: Re: [ovs-discuss] low bandwidth for gre > > Hello, > > If you prefer to not play with MTU settings every time, I`d recommend to > recompile this kernel setting all GRE options as a module and build > openvswitch module from vendor package, it will work perfectly with 1.9+ at > least. > > > On 01/07/2014 09:51 AM, Li, Chen wrote: >> eth4 MTU = 1500, and br-int MTU = 1200 => 2.76 Gbits/sec >> >> Also, I tested in Openstack environment, while all virtual ports MTU >> are 1500, and eth4 MTU = 9000 The bandwidth between 2 instances is about >> 2Gb/s. >> >> Thanks. >> -chen >> >> >> -----Original Message----- >> From: Zhou, Han [mailto:hzh...@ebay.com] >> Sent: Tuesday, January 07, 2014 1:46 PM >> To: Li, Chen; Chris Luke; 'Jesse Gross' >> Cc: discuss@openvswitch.org >> Subject: RE: [ovs-discuss] low bandwidth for gre >> >> Hi Chen, >> >> Are you sure it is only MTU change resulted in such a huge difference? >> It is hard to believe that fragmentation itself would lead to 9G -> 122K >> performance degradation. >> Could you try eth4 MTU = 1500, and br-int MTU = 1200? >> >> Best regards, >> Han >> >> -----Original Message----- >> From: discuss-boun...@openvswitch.org >> [mailto:discuss-boun...@openvswitch.org] On Behalf Of Li, Chen >> Sent: Tuesday, January 07, 2014 12:46 PM >> To: Chris Luke; 'Jesse Gross' >> Cc: discuss@openvswitch.org >> Subject: Re: [ovs-discuss] low bandwidth for gre >> >> O. >> Thanks for the reply. >> I just tried... And it works great !! >> I can achieve 9.84 Gbits/sec now while br-int has MTU 8000, while eth4 has >> MTU 9000. >> >> Thanks a lot for the help ! >> >> -chen >> >> -----Original Message----- >> From: Chris Luke [mailto:chr...@flirble.org] >> Sent: Tuesday, January 07, 2014 11:46 AM >> To: Li, Chen; 'Jesse Gross' >> Cc: discuss@openvswitch.org >> Subject: RE: [ovs-discuss] low bandwidth for gre >> >> No, he means the physical interface needs a larger MTU than the logical one. >> The physical one has to transport the packets your logical interface accepts >> plus the header data for GRE. If there isn't enough headroom then it must >> split the packet in two and reassemble at the far end - a slow process. >> >> Chris. >> >> >> >> >>> -----Original Message----- >>> From: discuss-boun...@openvswitch.org [mailto:discuss- >>> boun...@openvswitch.org] On Behalf Of Li, Chen >>> Sent: Monday, January 06, 2014 22:23 >>> To: Jesse Gross >>> Cc: discuss@openvswitch.org >>> Subject: Re: [ovs-discuss] low bandwidth for gre >>> >>> Sorry, I'm really new to network area. >>> >>> So, you mean I should keep the sender under the low MTU, while the >>> receiver with higher MTU size ?? >>> >>> But, how I can make sure the sender is always the sender ???? >>> >>> Thanks. >>> -chen >>> >>> -----Original Message----- >>> From: Jesse Gross [mailto:je...@nicira.com] >>> Sent: Tuesday, January 07, 2014 11:20 AM >>> To: Li, Chen >>> Cc: discuss@openvswitch.org >>> Subject: Re: [ovs-discuss] low bandwidth for gre >>> >>> If you change the MTU of both interfaces then it will still result in >>> fragmentation. >>> >>> On Mon, Jan 6, 2014 at 9:50 PM, Li, Chen <chen...@intel.com> wrote: >>>> Yes, fragmentation do affect the bandwidth. >>>> >>>> I run command to change interfaces' MTU size to test if >>>> fragmentation >>> makes a difference. >>>> ifconfig eth4 mtu ${mtu_size} >>>> ifconfig br-int mtu ${mtu_size} >>>> >>>> The default MTU = 1500 => 122 Kbits/sec >>>> MTU = 3000 => 419 Kbits/sec >>>> MTU = 6000 => 780 Kbits/sec >>>> MTU = 9000 => 1.14 Mbits/sec >>>> >>>> >>>> But, what I don’t understand is, I didn’t see really high CPU%. >>>> >>>> Also, there is no other way to improve the bandwidth ? >>>> Even under MTU=9000, 1.14 Mb/s vs. 10 Gb/s, the gap between the test >>> result we can get and the physical NIC is unacceptable!! >>>> >>>> >>>> Thanks. >>>> -chen >>>> >>>> >>>> -----Original Message----- >>>> From: Jesse Gross [mailto:je...@nicira.com] >>>> Sent: Tuesday, January 07, 2014 10:32 AM >>>> To: Li, Chen >>>> Cc: discuss@openvswitch.org >>>> Subject: Re: [ovs-discuss] low bandwidth for gre >>>> >>>> Well did you at least see if fragmentation makes a difference? >>>> >>>> On Mon, Jan 6, 2014 at 8:14 PM, Li, Chen <chen...@intel.com> wrote: >>>>> But 122 Kbits/s vs. 9.41Gb/s ?? >>>>> >>>>> Is this correct ??? >>>>> >>>>> How can I improve it ?? >>>>> >>>>> >>>>> Thanks. >>>>> -chen >>>>> >>>>> >>>>> -----Original Message----- >>>>> From: Jesse Gross [mailto:je...@nicira.com] >>>>> Sent: Tuesday, January 07, 2014 12:24 AM >>>>> To: Li, Chen >>>>> Cc: discuss@openvswitch.org >>>>> Subject: Re: [ovs-discuss] low bandwidth for gre >>>>> >>>>> On Sun, Jan 5, 2014 at 11:58 PM, Li, Chen <chen...@intel.com> wrote: >>>>>> Hi list, >>>>>> >>>>>> >>>>>> >>>>>> I’m working under CentOS, so the kernel is >>>>>> 2.6.32-358.123.2.openstack.el6.x86_64. >>>>>> >>>>>> openvswitch.x86_64 1.11.0_8ce28d-1.el6ost >>>>>> >>>>>> >>>>>> >>>>>> I have two physical machine in the test, each of them have a 10 Gb >>>>>> NIC >>> card. >>>>>> >>>>>> The bandwidth between the two machine using iperf can achieve >>> 9.41Gb/s. >>>>>> >>>>>> >>>>>> >>>>>> After enable gre follow guide >>>>>> http://networkstatic.net/configuring-vxlan-and-gre-tunnels-on-open >>>>>> vs >>>>>> w >>>>>> i >>>>>> tch/#!prettyPhoto >>>>>> >>>>>> The bandwitdth between the two nodes are really low. >>>>>> >>>>>> Only 122 Kbits/s !!!! >>>>> >>>>> At a minimum, fragmentation is presumably occurring. >>> _______________________________________________ >>> discuss mailing list >>> discuss@openvswitch.org >>> http://openvswitch.org/mailman/listinfo/discuss >> >> _______________________________________________ >> discuss mailing list >> discuss@openvswitch.org >> http://openvswitch.org/mailman/listinfo/discuss >> _______________________________________________ >> discuss mailing list >> discuss@openvswitch.org >> http://openvswitch.org/mailman/listinfo/discuss >> > _______________________________________________ discuss mailing list discuss@openvswitch.org http://openvswitch.org/mailman/listinfo/discuss
