Learn a bit more about SSDs
I've been pushed into learning a bit more about current SSD architectures in the past few weeks; we're bringing up a new database server and the powers that be want to run it on SSDs.
There are two competing architectures for SSDs currently, Single Layer Cell and Multi Layer Cell. The SLC drives are typically "faster", at least on writes, while the MLC drives have much better density and are therefore cheaper. MLC drives typically use a controller chip that essentially turns the drive into stripe sets in order to speed up the long-ish write cycles, and so the performance can depend much based on the controller.
Current generation MLC drives seem to have quite good write performance, certainly better than garden variety SATA drives. The SLC drives have astonishing performance, especially in small random read/writes, like say a database server?
So our new database server will use a pair of mirrored MLC drives for the OS and applications, and a pair of mirrored SLC drives for the database. We haven't decided where to put the database logs yet, perhaps on another MLC drive.
Last night, for grins, I installed FreeBSD 7.2 amd64 on one of the MLC drives. It took 4 mins 50 secs for the installer to write all of the files to disk, doing a full install of sources, binaries, and X. That's pretty fast. make -j 4 buildworld on the clean system took just over 40 minutes, which is a record for me. This is relatively mundane hardware, Athlon X2 4850e (low-power), 4GB DDR2 ram.
I know I'm replying to an old posting, but wanted to provide up to date information for people searching for FreeBSD and SSD now.
Summary: read some reviews and pick either an SLC device, or an MLC device with a modern controller. Intel and OCZ both seem to score very well.