DragonFly users List (threaded) for 2005-03
Re: SATA problem
Matthew Dillon wrote:
:On Thu, 31 Mar 2005, Bill Hacker wrote:
:> Look at the slices and note that there is 'unused'
:> (and unusable) space showing. Drives will reserve
:> space for a pool of replacements for bad blocks.
:> An OS will reserve a bit more.
:Aren't these ununsed areas due to simple alignment
:issues? I was under the impression that the bad block
:management is completely seamless, being one layer
:down, so to speak. Right or wrong?
:/Jonas Sundström. www.kirilla.com
Right. Spare blocks are invisible to the operating system.
. .'nowadays'. ..and 'even to its utilities'. 'T'weren't always thus.
Even SCSI drives once shipped with the known-bad blocks engraved
on the housing. Low-level utilities were used to edit and update the
bad block tables. Frequently! Novell kept a 'hot patch' reserve.
Started to disappear sometime after Schreech*GRATE* bought the
Imprimus/CDC Wren line .. 1991/2 or so?
Modern platter coating materials don't even have
the same nature or failure modes as the older stuff.
Todays' plating technology provides media
that usually outlasts the bearings, motors, and