Re: Are linux-fs's drive-fault-tolerant by concept?

[John Bradford]

> > I know you favor a layer between low-level driver and fs
> > probably. Sure it is clean design, and sure it sounds like
> > overhead (Yet Another Layer).
> 
> Wrong again - its actually irrelevant to the cost of mirroring data, the cost
> is entirely in the PCI and memory bandwidth. The raid1 management overhead is
> almost nil

Actually what I was suggesting was even simpler - in the unlikely
event that we were talking about an MFM or similar interface disk that
_was_ basically like a big floppy, and did no error correction of it's
own, we _could_ reserve, say, one sector per track, and create a 
fault tollerant device that substituted the spare sector in the event
of a write fault.

The overhead would probably be exactly zero, becuase nobody would
actually compile the feature in and use it :-).

John.