Messages in this thread | | | Date | Tue, 19 Mar 2002 22:56:09 +0100 | From | Vojtech Pavlik <> | Subject | Re: [patch] My AMD IDE driver, v2.7 |
| |
On Tue, Mar 19, 2002 at 10:21:30PM +0100, Pavel Machek wrote: > Hi! > > > > > commands. With the proper sequencing, you can even do power management > > > > of the drives in userspace. You don't want to do system suspend/resume > > > > that way, but you can certainly have a userspace policy daemon running, > > > > that powers-down and powers-up the drives, etc. > > > > > > See noflushd, Hdparm is able to powersave disks well, already, and it > > > was in 2.2.X, too. > > > > Not all of them safely, though. Many a drive will corrupt data if it > > receives a command when not spinned up. You need to issue a wake command > > first, which hdparm doesn't, it just leaves it to the kernel to issue a > > read command or whatever to wake the drive ... > > Is this common disk bug, or are they permitted to behave like that?
This behavior is permitted by the specification, as far as I know - results of commands other than wakeup (and other pm commands) in sleep or suspend mode are undefined ...
-- Vojtech Pavlik SuSE Labs - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |