[j-nsp] JunOS 9.4R1.8 - Memory Leak?

[Tore Anderson]

Hey,

> I'll keep you posted if I learn more, and thanks in advance for doing
> the same...

The fine folks from nLogic and JTAC have a theory now, which is that the
leak is related to a new process introduced in 9.4 called "lpdfd".  It's
not something I've been using, so disabling it was not a problem for me:

system {
    processes {
        local-policy-decision-function disable;
    }
}

The process was logging to files in the directory "/mfs/var/lpdfd",
which is mounted on a memory-backed block device.  This is the actual
leak, it seems.  I deleted all the logs, but suprisingly enough it
didn't cause the memory utilisation (as reported by "show chassis
routing-engine") to drop sharply.  However, it seems like the router now
has stopped leaking!  The memory utilisation is down to 93% - it was at
96% right before "lpdfd" was disabled and had been slowly but steadily
increasing up until that point.

I had disabled the process on my other MX too, but I have not yet
deleted its log files.  So far it looks like the memory usage on that
one has flatlined.  I suspect that the memory freed up by deleting the
files is reclaimed only when needed, and that's why I see a (small) drop
in memory utilisation on the router where the log files were deleted only.

I'll have to monitor the memory utilisation on the routers for a few
more days before I can be certain that we've nailed the bug, though, but
I'm feeling optimistic.  You'll probably want to try disabling the
process yourself.  Let me know how it goes!

Best regards,
-- 
Tore Anderson
Redpill Linpro AS - http://www.redpill-linpro.com/