[Xorp-hackers] heavy CPU use for xorp_fea on startup

[Ben Greear]

Pavlin Radoslavov wrote:
> Ben Greear <greearb at candelatech.com> wrote:
> 
>> I am trying to start 30 xorp instances on a system with
>> around 600 interfaces (vlans and such).  My hardware has lots
>> of RAM and a quad-core CPU, but it still takes more than the 10
>> second keep-alive timeout to get xorp_fea initialized (it seems
>> to be reading large numbers of netlink messages).  This causes
>> continual xorp restarts since the timeout fails.
> 
> What kind of netlink messages the FEA sees from the kernel?

Not sure sure...I just did a quick strace and saw lots of netlink
socket reads.

I'll try to get oprofile configured and see if that gives me any
clues about performance hotspots...

> On startup it queries info about all interfaces in the system.
> This info is needed for various reasons. E.g., if later it is
> reconfigured and on shutdown it is suppose to restore the original
> state.

Does it really need to probe interfaces that it is not configured
to use?  It seems like it could ignore them until it is asked to
use them...or, at least just probe them very minimally.

Anyway...this is mostly theoretical as you noted.  I'll try to get
some solid profile data...

Ben

-- 
Ben Greear <greearb at candelatech.com>
Candela Technologies Inc  http://www.candelatech.com