Quggaa locking hard.

[alexpalias-bsdstable at yahoo.com]

I have also seen this with a recent version of FreeBSD 8 (I know 8.0-BETA2 didn't have this problem, also I have an 8.0-RC1 without problems,  but I think RC3 did have it, and I'm sure -RELEASE has it).

A few more details:  

It happened both on amd64 and i386.  I couldn't debug amd64 (it was a live server and we couldn't afford it), but on i386 flowcleaner was using a LOT of CPU.  

It seemed to happen after booting, when quagga was importing global routing tables (~300k routes) from 2 BGP sessions.  At least one of the sessions seemed to finish importing routes, but the kernel routing table seemed to be growing very slowly.  

Doing "netstat -nr | wc -l" took way longer than usual (20-30 seconds versus 9 seconds now), and it only reported about 100k routes.  Doing it again after a minute or so showed the number of routes grew by around 10k.

During this time, both quagga and zebra were very slow to respond to a new telnet session opened to them.

As a workaround, I did sysctl net.inet.flowtable.enable=0.  This didn't ease the load on the CPU, but having it in /etc/sysctl.conf and rebooting did help (quagga started up normally and all routes are where they should be).

Hope this helps
    Alex

--- On Fri, 12/4/09, Zaphod Beeblebrox <zbeeble at gmail.com> wrote:

> From: Zaphod Beeblebrox <zbeeble at gmail.com>
> Subject: Quggaa locking hard.
> To: "FreeBSD Stable" <freebsd-stable at freebsd.org>
> Date: Friday, December 4, 2009, 5:46 AM
> I'm still investigating this, but my
> quagga is locking hard on FreeBSD 8.0
> and not locking hard on 7.2.  It seems (at this early
> point in the
> investigation) that both bgpd and zebra are wedging and
> zebra is listed as
> being in the "RUN" state.
> 
> curiously, the load is also 4.0 (exactly the number of
> cores in the machine)
> even though the machine also reads 100% idle.
>