Benchmarking tools, methods

Hello,

I'm going to be testing some new hardware (see http://archives.postgresql.org/pgsql-performance/2011-11/msg00230.php)
andwhile I've done some very rudimentary before/after tests with pgbench, I'm looking to pull more info than I have in
thepast, and I'd really like to automate things further. 

I'll be starting with basic disk benchmarks (bonnie++ and iozone) and then moving on to pgbench.

I'm running FreeBSD and I'm interested in getting some baseline info on UFS2 single disk (SATA 7200/WD RE4), gmirror,
zfsmirror, zfs raidz1, zfs set of two mirrors (ie: two mirrored vdevs in a mirror).  Then I'm repeating that with the 4
Intel320 SSDs, and just to satisfy my curiosity, a zfs mirror with two of the SSDs mirrored as the ZIL. 

Once that's narrowed down to a few practical choices, I'm moving on to pgbench.  I've found some good info here
regardingpgbench that is unfortunately a bit dated:  http://www.westnet.com/~gsmith/content/postgresql/ 

A few questions:

-Any favorite automation or graphing tools beyond what's on Greg's site?
-Any detailed information on creating "custom" pgbench tests?
-Any other postgres benchmarking tools?

I'm also curious about benchmarking using my own data.  I tried something long ago that at least gave the illusion of
working,but didn't seem quite right to me.  I enabled basic query logging on one of our busier servers, dumped the db,
andlet it run for 24 hours.  That gave me the normal random data from users throughout the day as well as our batch
jobsthat run overnight.  I had to grep out and reformat the actual queries from the logfile, but that was not
difficult.  I then loaded the dump into the test server and basically fed the saved queries into it and timed the
result. I also hacked together a script to sample cpu and disk stats every 2S and had that feeding into an rrd database
soI could see how "busy" things were. 

In theory, this sounded good (to me), but I'm not sure I trust the results.  Any suggestions on the general concept?
Isit sound?  Is there a better way to do it?  I really like the idea of using (our) real data. 

Lastly, any general suggestions on tools to collect system data during tests and graph it are more than welcome.  I can
homebrew,but I'm sure I'd be reinventing the wheel. 

Oh, and if anyone wants any tests run that would not take an insane amount of time and would be valuable to those on
thislist, please let me know.  Since SSDs have been a hot topic lately and not everyone has a 4 SSDs laying around, I'd
liketo sort of focus on anything that would shed some light on the whole SSD craze. 

The box under test ultimately will have 32GB RAM, 2 quad core 2.13GHz Xeon 5506 cpus and 4 Intel 320 160GB SSDs.  I'm
recyclingsome older boxes as well, so I have much more RAM on hand until those are finished. 

Thanks,

Charles

ps - considering the new PostgreSQL Performance book that Packt has, any strong feelings about that one way or the
other? Does it go very far beyond what's on the wiki?