Smartdrv equivalent in Linux and other questions
 

Is there a smartdrv equivalent in Linux?
Is the kernel responsible for file caching? Or is it a start-up daemon?
What about hdparm? Does it do more than just settings tweak?
Can you set how much ram to allocate for the cache like in smartdrv?

Sorry for asking too many questions at once... :)

You'll have to more specific about what Smartdrv does (IIRC, it was a MS-DOS thing ?)

Linux automatically uses memory that isn't allocated for programs to cache, so RAM will always appear nearly full. There's also a "readahead" service enabled on some newer distributions like FC3 to optimise disk, similar to what XP does. Unlike Windows, Linux is generally designed to make maximum use of RAM to minimise disk writes.

hdparm just changes settings - to get full info type this in a terminal window:

man hdparm

It can also benchmark hard drives (-t and -T command line switches).