>From: Andy Polyakov <[EMAIL PROTECTED]>

>As for DVD-RW on the other hand. If *minimally* formatted for Restricted
>Overwrite, DVD-RW still can be recorded only *sequentially*. This makes
>it virtually impossible to use *minimally* formatted DVD-RW media for
>housing of live read-write file system. Only once fully formated (which
>takes 1 hour for 1x media), DVD-RW permits for random write, but with
>32KB granularity. Latter means that you either have to have special
>kernel driver which would arrange for 32KB granularity or modify file
>system code to do same thing. Now note that no work (at least no visible
>outcome so far) has been done to accomplish either of these two
>alternatives under Linux (or any other Unix implementation), [presumaly]
>because it's damn hard. A.

So DVD+RW drives do things in firmware what you need to do in the kernel
if you like to have 2k granularity with DVD-RW. But this is nothing a new
firmware could not support.

Note that the kernel also first reads a 512 byte sector from a hard disk 
if you like to write only 64 bytes.

AFAIK, DVD+RW also use the basic DVD physical sector size of 32k.


J�rg

-- 
 EMail:[EMAIL PROTECTED] (home) J�rg Schilling D-13353 Berlin
       [EMAIL PROTECTED]                (uni)  If you don't have iso-8859-1
       [EMAIL PROTECTED]        (work) chars I am J"org Schilling
 URL:  http://www.fokus.fraunhofer.de/usr/schilling ftp://ftp.berlios.de/pub/schily


-- 
To UNSUBSCRIBE, email to [EMAIL PROTECTED]
with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]

Reply via email to