[development] For review/input: HOWTO: Benchmark Drupal code

[Angela Byron]

(Yes, technically this is a documentation thing, but it needs  
developer input and I know a lot of you aren't on the docs list)

I've put up a kind of 'skeleton' handbook page on how to benchmark  
Drupal code here:

http://drupal.org/node/79237

This whole benchmarking thing was kind of an arcane voodoo art thing  
to me until recently (and actually to a large extent still is ;)),  
but I noticed increasingly coming across patches that basically say  
"Let's see some benchmarks before we even think about committing this  
to core." I figured there might be other people in the same boat as  
me, so thought it would be good to document how this was done so  
we're not reliant on only a handful of people (Dries, killes, etc.)  
to do it.

Most of the stuff I've documented is in the area of setting up a  
performance testing environment.. I think that part's pretty solid,  
but I'd really appreciate any additional feedback people have on:

- "Tools of the trade"
- Tricks that are helpful
- How to interpret results
- (maybe?) How to take raw ab output and turn it into pretty graphs  
like on Dries's site
- other stuff

Thanks in advance for any help!
-Angie