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Laptops, power management, and Ubuntu

Laptops, power management, and Ubuntu

Posted Nov 11, 2007 16:47 UTC (Sun) by jengelh (subscriber, #33263)
In reply to: Laptops, power management, and Ubuntu by jimparis
Parent article: Laptops, power management, and Ubuntu

It would be a wonderful world if this was the case. The Toshiba MK2003GAH is one of these
drives that do parking anyway, even if you -B255 it. Only solution was to write a kernel-level
workaround module (I called it thkd) that periodically reads small amounts from the disk.


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Laptops, power management, and Ubuntu

Posted Nov 11, 2007 17:29 UTC (Sun) by jimparis (subscriber, #38647) [Link]

-B255 is reserved, it's no surprise that it still parks the heads.

Laptops, power management, and Ubuntu

Posted Nov 11, 2007 17:31 UTC (Sun) by jimparis (subscriber, #38647) [Link]

Wait, maybe you meant it also parks with -B128 through -B254, in which case I agree, yes, that
sucks.  I'm not sure why you need a kernel module though, seems a small user-space utility
that does periodic reads with O_DIRECT would work just as well.

Laptops, power management, and Ubuntu

Posted Nov 11, 2007 17:39 UTC (Sun) by jengelh (subscriber, #33263) [Link]

Because the kernel module is smaller (11KB - what, who bloated that up?), does not need glibc,
or anything and runs as early as possible without having to mess with the
distribution-specific boot scripts. Rebuilding the initrd _with_ your changes is often a real
pita.

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