Re: [gentoo-user] HDD with too aggressive power management

[Alan McKinnon <alan.mckinnon@gmail.com>]

Apparently, though unproven, at 23:09 on Monday 31 January 2011, Nils Holland 
did opine thusly:

> Hi folks,
> 
> I've got an Asus X7BJ-something laptop here that by default (i.e. when
> installing plain Gentoo on it) seems to do too aggressive power
> management for its hard drive. That is, already after only about five
> seconds(!!) of inactivity, the HDD spins down. This is kind of insane
> - you edit some small file, only half a minute later when you save it,
> you have to wait for what feels like ages for your HDD to spin back up
> and actually do something. ;-)
> 
> The first thing I tried was having a look at the BIOS to see if HDD
> power management can be disable there. But no sir, no such option. Ok,
> no problem I thought, and emerged "hdparm", which I have added to my
> default runlevel, so that it gets executed with the arguments "-B 254
> -S 0" upon each boot. That seems to fix it, HDD power management is
> off and no more unwanted spindowns occur.
> 
> However, now comes the problem: It seems that whenever I change from
> wall power to battery power (probably also vice versa, but I haven't
> tested this often enough), the machine's HDD forgets about the
> settings I've made using "hdparm" and starts spinning down right again
> after only a few seconds of inactivity. That sucks.

Running KDE with PowerDevil perhaps?






> 
> Of course, manually executing "hdparm -B 254 -S 0 /dev/sda" after
> unplugging the machine fixes the issue again. However, something more
> "automated" would be prefered.
> 
> First thing, I'm wondering if the change in power management
> parameters is actually caused by something at the OS level. I haven't
> set up any such thing explicitly, so I believe that it's something the
> machine just "does" outside of the OS's control. As it can be
> overridden by executing "hdparm" manually, what I would need is probably
> a place where I can hook in with a little shell script that gets
> executed every time the system's power source changes, and does
> nothing else than just execute "hdparm" with the appripriate
> parameters. So much about the theory, but then I don't really have an
> idea what I'd have to do to get a script to run every time the power
> source changes. And that's why I'm writing this message, as any
> suggestions that could point me into the right direction are very
> welcome. ;-)
> 
> Greetings and thanks in advance,
> Nils

-- 
alan dot mckinnon at gmail dot com