Laptop: Hard drive wakes up every 5-10 seconds

[Kevin Kofler]

Peter Arremann wrote:
> Be careful with the -S values over 240. If you read the man page, values
> over 240 are interpreted differently than lower values and unfortunately
> there is no complete list of which drives interpret it how... I had a
> really old drive where 255 reset the firmware. I tried over values and
> when I hit 250, the drive locked up ...

Well, the manpage claims the behavior of 255 is actually well-defined except
for older drives. That said, the behavior of values above 240 is indeed not
intuitive (even for the drives which do follow the specs), bad me for not
RTFM before playing around with it.

Looks like 0 is actually the best value to use according to the manpage, as
it disables that timeout completely (hopefully it won't also do weird
things on some older drives). 240, or maybe even 239, just in case, is
probably the safest.

The manpage also says that -B 255 (disable advanced power management
entirely) doesn't always work, so -B 254 is also worth a try.

        Kevin Kofler