Re: 'let the hdd remap the bad blocks'

[Oleg Drokin <green@namesys.com>]

Hello!

   Basically uyou'd better search for this on HDD vendors sites.
   What's going on is simply can be described this way:
   You write some block to HDD, if HDD decides the block is bad for some reason
   and remapping is allowed (usually by tiurning on SMART), block is written to
   different on-platter location and drive adds one more entry to its
   remaped-blocks list. Next time you read this block, drive consults its
   remapped blocks list and if block is remapped, reads it from new location
   with correct content.
   Described mechanism works for writing.
   Actually I've seen something that looks like remapping on read, though 
   I have no meaningful explanation for that (except that they may have some
   extra redundant info stored when you write data to disk, so that if sector
   cannot be read, its content is restored with that redundant information and
   sector is then remapped.). And this process takes a lot of time.

Bye,
    Oleg
On Mon, Aug 19, 2002 at 03:58:30PM +0100, Newsmail wrote:
> Hello Hans and Oleg,
> maybe its an offtopic question, but Hans always talks about leaving the 
> hard disk to remap the bad blocks by itself. could you explain it in some 
> words, how all this works, what happens after, and since when it exists, or 
> do you have any special URL explaining this?
> thx in advance,
> greg
> 
> 
>