[ltp] silent t41

[U Kuehn]

Atte André Jensen wrote:
> Hi
> 
> I installed debian (ran ubuntu before) on my t41 and a really nice
> surprise was that it's completely silent (hd spindown and staying there)
> when running on batteries. Unfortunately I have no idea what package
> does that. My questions are:
> 
> 1) What causes the spindown to happen?
> 

laptop-mode-tools in debian.

> 2) What (besides the spin up time when spun down) are the drawbacks of
> this feature?
> 
Dirty buffers (unwritten pages) are kept much longer in memory,
typically up to 10 minutes, so you can lose that much work. But I
remember seeing that the script disables this behavior when battery is low.

> 3) Wouldn't it make sense to have that silent mode on all the time? And
> how could I achieve that (so hd spindown even when running on power)?
> 
I was told that laptop hard disks are not build to run all the time due
to the way the bearings are constructed (fitting when cold). And the
disks are specified for a lot of spin-up/downs (_desktop_ disks are
not!). However, check the specs of your model to make sure that it's
sufficiently high (>200000).

Cheers,
Ulrich