[c-nsp] 7206vxr cpu usage.

[Euan Galloway]

On Thu, Mar 05, 2009 at 03:22:05PM -0800, Keith wrote:

> Since then, the router CPU has gone up by about 10%. Normally at this time
> of day its about 22-23%, it is now about 32%. Normally at peak times the
> CPU barely broke 25%. I'm guessing but it looks like it might break 40% at
> peak times now.
> 
> Is the router working harder because of the GBIC and using gig ethernet
> rather than faste? We were using a gig port on the NPE at 100 meg.

The main BCM1250 processor on the NPE-G1 is what provides the gig ports on 
the NPE. It shouldn't be too surprising to find that it's easier to just pass 
bits around inside the CPU rather than out through the processor's seperate 
PCI I/O capability to reach the PCI backplanes in the VXR chassis in order to 
chat with the PA-GEs.

The performance figures for an NPE-G1 are always onboard to onboard.
Using a PA really takes the edge off of the NPE-G1. 

I've not yet had a play with the 7201 which is similar but different, in that 
none of the onboard are on the main CPU, but 3 are "directly" on one supporting 
chip, and the fourth is hung of that chip's PCI-X bus. 

I wonder what interesting brokenness awaits there.

-- 
Euan Galloway