Hi,
On Sat, 2 Mar 2013 18:53:45 +0200 Maxim Kammerer <mk@???> wrote:
> On Fri, Mar 1, 2013 at 7:34 PM, intrigeri <intrigeri@???> wrote:
> > commit 65c78a5594ba7fff98683959d46bf431a065b77d
> > Author: Tails developers <amnesia@???>
> > Date: Fri Mar 1 13:17:54 2013 +0100
> >
> > Enable laptop-mode-tools hard drive power management settings.
> >
> > Set APM level to 127 on battery, and to 254 on AC power, as a
> > Wheezy desktop system does.
> >
> > 254 is chosen to avoid causing excessive head load/unload
> > cycles.
> > 127 is chosen because the head parking is very useful for shock
> > protection.
>
> Don't use 127, see commit 4686bd8a in Liberté's git.
> https://github.com/mkdesu/liberte/commit/4686bd8a
>
Why do you think 127 is bad?
Documentation of hdparm for this option reads:
Query/set Advanced Power Management feature, if the drive
supports it. A low value means aggressive power management and
a high value means better performance. Possible settings range
from values 1 through 127 (which permit spin-down), and values
128 through 254 (which do not permit spin-down). The highest
degree of power management is attained with a setting of 1, and
the highest I/O performance with a setting of 254. A value of
255 tells hdparm to disable Advanced Power Management
altogether on the drive (not all drives support disabling it,
but most do).
127 is the option allowing better performance while maintaining
spindown, which seems resonable on battery. Please explain why do you
think it is bad.
> > Note that NOLM_AC_HD_POWERMGMT=254 is there since the beginning — as
> > usual, bottom-up approach produces better results.
>
> Although LM_AC_HD_POWERMGMT=128 — oh well, I guess users who
> experience issues can stop laptop_mode service. Having 254 for
> everyone on AC is unreasonable, in my opinion.
>
Why? Again, reading the documentation it seems a good choice, so please
explain and give sources for your opinion.
Cheers
