Messages in this thread |  | | From | Ian Stirling <> | Subject | Re: Journaling pointless with today's hard disks? | Date | Tue, 27 Nov 2001 01:01:19 +0000 (GMT) |
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> > At 12:49 AM +0100 11/27/01, Martin Eriksson wrote: > >I sure think the drives could afford the teeny-weeny cost of a power failure <snip> > converter, which is expensive. If you simply detect a drop in dc > power, there simply isn't enough margin to reliably write a block. > > Years (many years) back, Diablo had a short-lived model (400, IIRC) > that had an interesting twist on this. On a power failure, the > spinning disk (this was in the days of 14" platters, so plenty of > energy) drove the spindle motor as a generator, providing power to > the drive electronics for several seconds before it spun down to > below operating speed.
I have a (IIRC) elantec databook from 1985 or so, that I've found chips in disks from the MFM/RLL PC era. These are motor driver chips aimed at PCs, which support generation using the motor. - 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/
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