lost+found

[Chuck Swiger]

Jerlique Bahn wrote:
> 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? 

Yes, it's still possible.

> 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.

The cache on the RAID card will be flushed OK, but any in-process operations 
by live processes will be interrupted in the middle if the OS goes away. 
While some operations are atomic (things like unlink or move), simply writing 
pieces out is not...

> What should I be looking for?
> 
> I would like to also know how to turn off (or check) caching on the physical
> disk itself.

smartmontools port?  sysctl hw.ata.wc...?

-- 
-Chuck