Re: Head parking (was: IBM HDAPS things are looking up)

[Pekka Enberg <penberg@gmail.com>]

On 7/7/05, Jens Axboe <axboe@suse.de> wrote:
> Did it say 'head parked'? If the drive is idle, you wont hear anything.
> Laptop drives auto-park really quickly themselves. A time ./park
> /dev/hda should tell you whether it needed to park or not, if it
> executes faster than a few hundred ms it was already parked.

Aah, you're right.

haji tmp # time ./a.out /dev/hda
head parked

real    0m0.421s
user    0m0.000s
sys     0m0.001s

Immediately after that:

haji tmp # time ./a.out /dev/hda
head parked

real    0m0.001s
user    0m0.000s
sys     0m0.001s

And then I do bit of disk reads and I get this again:

haji tmp # time ./a.out /dev/hda
head parked

real    0m0.429s
user    0m0.001s
sys     0m0.001s

So looks like it works for me too.

                                Pekka
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