RE: [j-nsp] BGP memory consumption

From: Tony Mumm (tonym@netins.net)
Date: Fri Feb 16 2001 - 12:35:58 EST


-----BEGIN PGP SIGNED MESSAGE-----

Thanks for the clarification..it helps.

Is there any way (or reason) to monitor the usage of that SRAM on the
IP2?

In addition to that, would it be useful or possible to see the memory
usage of the ssb/scb/sfm/sbr ? From show chassis ssb, I don't see
anything that really gives an indication.

After what you said, I doubt there is a limit to be concerned
about...but then I'm a box information freak that likes to know the
stats...

Thanks,

Tony

- -----Original Message-----
From: Robert Craig [mailto:rcraig@juniper.net]
Sent: Friday, February 16, 2001 9:26 AM
To: Tony Mumm
Cc: nicholas harteau; Josh Richards; juniper-nsp@puck.nether.net
Subject: Re: [j-nsp] BGP memory consumption

Actually, with the show pfe route summary command, you are looking at
the
memory utilization for the forwarding table stored in DRAM in the pfe
controller (scb|ssb|sfm|sbr). The static RAM used by the IP2 will
hold
approximately 540,000 IPv4 routes.

Robert.

> -----BEGIN PGP SIGNED MESSAGE-----
>
> Our peer there is also doing similar memory usage..roughly 117 MB
> for that many peers. The question I counter with, is PFE memory
> requirements. It appears that the pfe uses 8 MB of super high
> quality RAM to record next-hops for the IP2 ASIC (assumption on my
> part). From show pfe route summary, it appears a router is using
> 5.8 of this to run ~100k routes. Now I don't know how this is
> going to scale in relation to the number of routes, but if you just
> use a simple one to one relationship the router will top out at
> around 140k routes. This number is based on roughly 59 bits per
> route in
> memory... again, entirely guesstimates.
>
> Obviously the rest of the pfe subsystem has 64 MB of ram...but I
> don't know how this applies..
>
> I'm not trying to be negative here, just want to see if anyone else
> has thought of this?
>
> Thanks,
>
> Tony
>
> - -----Original Message-----
> From: nicholas harteau [mailto:nrh@ikami.com]
> Sent: Thursday, February 15, 2001 11:49 PM
> To: Josh Richards
> Cc: juniper-nsp@puck.nether.net
> Subject: Re: [j-nsp] BGP memory consumption
>
>
>
> Your juniper will have RIBs for each peer/protocol pair. In my
> experience the memory use scales linearly all else being equal.
> Also,
> I'd be hard-pressed to find a scenario outside of a lab where you
> will
> use more than the 768M of ram that the junipers support these days.
> My
> AADS router is using 128M with 55 peers and mbgp running as well as
> bgp.
>
> Josh Richards wrote:
> > How does Juniper's BGP memory consumption compare to, say, a
> > Cisco?
> >
> >
> > While the exact answer obviously varies depending on the peering
> > sessions, what magnitude of memory consumption can I expect to be
> > necessary for the first full transit view (~100,000 prefixes)
> > and each successive additional transit view of similar size?
> >
> > Is the memory consumption in such a way that I can assume that a
> > peer with, say, only 10,000 prefixes is going to consume 10% of
> > the amount of memory as the 100,000 prefix peer?
> >
> > Damn, I can't wait to get a few of these things in the lab...
> >
> > -jr
> >
> > ----
> > Josh Richards [JTR38/JR539-ARIN]
> > <jrichard@geekresearch.com/cubicle.net/fix.net/freedom.gen.ca.us>
> > Geek Research LLC - <URL:http://www.geekresearch.com/>
> > IP Network Engineering and Consulting
> >
>
> - --
> nicholas harteau
> nrh@ikami.com
>
> -----BEGIN PGP SIGNATURE-----
> Version: PGPfreeware 6.5.8 for non-commercial use
> <http://www.pgp.com>
>
> iQB1AwUBOo08t5dSAaybdldZAQEKDwL9GsRVT6yjTERDe+C5cLfK73zrxMhSKCXh
> allAFcly96OERTVAtfd+LlKbfe7Hm15cGDCjXlMLSNi5IP9V9QCkiTWJj7Hcb/Yz
> omPzsadPduCK8O61NXntKlyylQZfirTb
> =Qw8c
> -----END PGP SIGNATURE-----
>

-----BEGIN PGP SIGNATURE-----
Version: PGPfreeware 6.5.8 for non-commercial use <http://www.pgp.com>

iQB1AwUBOo1k/ZdSAaybdldZAQG9pwL8DDGKRaAoo1AcT4NLVYlOIKLup4AfntmC
tezsTHQqETZI1DUA2Yk2w2D7wk9dStlXrU7/6dN4akDIJU5cBaP7GEIoldwOfVP4
EpZSo36wvjbUhfa4nBvqAOHuXEyNOgYD
=rxmS
-----END PGP SIGNATURE-----



This archive was generated by hypermail 2b29 : Mon Aug 05 2002 - 10:42:40 EDT