Re: end to end error recovery musings

[Douglas Gilbert <dougg@torque.net>]

Martin K. Petersen wrote:
>>>>>> "Alan" == Alan  <alan@lxorguk.ukuu.org.uk> writes:
> 
>>> Not sure you're up-to-date on the T10 data integrity feature.
>>> Essentially it's an extension of the 520 byte sectors common in
>>> disk
> 
> [...]
> 
> Alan> but here's a minor bit of passing bad news - quite a few older
> Alan> ATA controllers can't issue DMA transfers that are not a
> Alan> multiple of 512 bytes without crapping themselves (eg
> Alan> READ_LONG). Guess we may need to add
> Alan> ap-> i_do_not_suck or similar 8)
> 
> I'm afraid it stops even before you get that far.  There doesn't seem
> to be any interest in adopting the Data Integrity Feature (or anything
> similar) in the ATA camp.  So for now it's a SCSI-only thing.
> 
> I encourage people to lean on their favorite disk manufacturer.  This
> would be a great feature to have on SATA too...

Martin,
SCSI to ATA Translation (SAT) is now a standard
(ANSI INCITS 431-2007) [and libata is somewhat
short of compliance].

Work on SAT-2 is now underway and one of the agenda
items is "end to end data protection" and is in the
hands of the t13 ATA8-ACS technical editor. So it
looks like data integrity is on the radar in the SATA
world.

See http://www.t10.org/ftp/t10/document.06/06-497r4.pdf
for more evidence of how SAS and SATA are converging
at the command and feature set level.

Doug Gilbert