All BFD sessions are handled on single thread?

[Sema Boyko]

Hi,
I have the following configuration on one of my servers ("10.1.0.1"):












*protocol bfd {    interface "eth0" {                min rx interval 200
ms;                min tx interval 1000 ms;                idle tx interval
1 s;                multiplier 5;    };    neighbor 10.1.0.2;    neighbor
10.1.0.3;    neighbor 10.1.0.4;  **  ..... (here about 1000 records)*
*    neighbor 10.1.3.251;*
*    neighbor 10.1.3.252;*
*    neighbor 10.1.3.253;*
*    neighbor 10.1.3.254;*
*}*


And I configured the second server ("10.1.0.2") as a neighbor with the
following config:










*protocol bfd {    interface "eth0" {                min rx interval 200
ms;                min tx interval 1000 ms;                idle tx interval
1 s;                multiplier 5;    };    neighbor 10.1.0.1;}*

For some reason I have random session expire events on the second server
and BFD sessions get UP -> DOWN, DOWN -> UP events.





*bird: bfd1: Session to 10.1.0.1 expiredbird: bfd1: Session to 10.1.0.1
changed state from Init to Downbird: bfd1: Session to 10.1.0.1 changed
state from Down to Initbird: bfd1: Session to 10.1.0.1 expiredbird: bfd1:
Session to 10.1.0.1 changed state from Init to Downbird: bfd1: Session to
10.1.0.1 changed state from Down to Init*


This happens only if I specify a lot of neighbors in the config. For
example the following config on first server ("10.1.0.1") works fine:











*protocol bfd {    interface "eth0" {                min rx interval 200
ms;                min tx interval 1000 ms;                idle tx interval
1 s;                multiplier 5;    };    neighbor 10.1.0.2;    neighbor
10.1.0.3;}*

Looks like all BFD sessions are handled on a single thread. Could someone,
please, confirm that BIRD isn't designed to handle a huge amount of BFD
sessions simultaneously? Or possibly I can enable some options to handle
this case in my env?
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