lost+found

[Jerlique Bahn]

Hello,

If I pull the power on my server whilst its doing heavy IO, should I get
files in lost+found if my raid card has battery backed cache? 

I was under the understanding that the file operations were atomic, and
hence freebsd's file system should have no corrupted files on the reboot.
The raid card says that it is flushing the cache of the card, yet freebsd
still experiences the corrupt files.

What should I be looking for?

I would like to also know how to turn off (or check) caching on the physical
disk itself.

JB