Hi,

There is a known issue with with Open vSwitch (OVS) performance with BGP.

Even without OVS we hit IRQ (too many) issue on "physical" network in our KVM

environment.

Official OVS quote:

> We'd accept patches to improve OVS's routing table code.  It's not
> designed to scale to 1,800,000 routes.  We'd also take code to suppress
> the routing table code in cases where it isn't actually needed, since
> it's not always needed.  But we can't take a patch to just delete it;
> I'm sure you understand.

I tried to apply this patch at that time, but was already useless for newer versions:

https://mail.openvswitch.org/pipermail/ovs-discuss/attachments/20161123/5379b333/attachment.bin

Our workaround was to scale VM with 3 vCPU-s, since our average system load is 1.5 for BGP.

You can see what is happening:

[root@bgp1 ~]# top

...

  PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND                                                                                                                          

  654 root      10 -10 1284492   1.0g  20276 R  98.0  27.0   2513:01 ovs-vswitchd                                                                                                                     

   16 root      20   0       0      0      0 S   2.0   0.0  24:45.60 ksoftirqd/1  

[root@bgp1 ~]# ip route show

...

1.0.0.0/24 via 89.212.xx.xx dev t2-v24-ha proto bird 

1.0.4.0/24 via 89.212.xx.xx dev t2-v24-ha proto bird 

1.0.4.0/22 via 89.212.xx.xx dev t2-v24-ha proto bird 

1.0.5.0/24 via 89.212.xx.xx dev t2-v24-ha proto bird

Routes being constantly added and deleted:

[root@bgp1 ~]# ip monitor

...

Deleted 2620:11d:6000::/42 via 2a01:xxx:xxx::1 dev t2-v26-ha proto bird metric 1024 pref medium

2620:11d:6000::/42 via 2a01:xxx:xxx::1 dev t2-v26-ha proto bird metric 1024 pref medium

Deleted 2620:11d:6000::/42 via 2a01:xxx:xxx::1 dev t2-v26-ha proto bird metric 1024 pref medium

2620:11d:6000::/42 via 2a01:xxx:xxx::1 dev t2-v26-ha proto bird metric 1024 pref medium

Deleted 2620:11d:6000::/42 via 2a01:xxx:xxx::1 dev t2-v26-ha proto bird metric 1024 pref medium

2620:11d:6000::/42 via 2a01:xxx:xxx::1 dev t2-v26-ha proto bird metric 1024 pref medium

Deleted 68.69.37.0/24 via 89.212.xx.xx dev t2-v24-ha proto bird 

68.69.37.0/24 via 89.212.xx.xx dev t2-v24-ha proto bird 

Deleted 103.115.180.0/22 via 89.212.xx.xx dev t2-v24-ha proto bird 

103.115.180.0/22 via 89.212.xx.xx dev t2-v24-ha proto bird 

Deleted 103.115.180.0/22 via 89.212.xx.xx dev t2-v24-ha proto bird 

103.115.180.0/22 via 89.212.xx.xx dev t2-v24-ha proto bird 

Deleted 2.16.70.0/23 via 89.212.xx.xx dev t2-v24-ha proto bird 

Deleted 88.221.28.0/22 via 89.212.xx.xx dev t2-v24-ha proto bird 

Deleted 23.50.188.0/22 via 89.212.xx.xx dev t2-v24-ha proto bird 

Deleted 92.122.68.0/22 via 89.212.xx.xx dev t2-v24-ha proto bird 

Deleted 88.221.100.0/22 via 89.212.xx.xx dev t2-v24-ha proto bird 

Deleted 92.123.208.0/22 via 89.212.xx.xx dev t2-v24-ha proto bird

..... 

Regards,

saso

On 8 Jul 2020, at 08:05, Mike Neo <neomikemac@gmail.com> wrote:

Hi,

what is your experience with installing bird on virtual server (ESXi)? Is there any limitation of this kind of deployment for example problems with performance etc.?

Regards,

Mike