[mythtv-users] Re: DMA not enabled

[Steve Adeff]

On Thursday 13 October 2005 13:13, Kirk Bocek wrote:
> I've used hdparm -Tt on all sorts of non-IDE devices: flash-memory drives,
> Raid devices, RAM drives. It's never been a problem.
>
> Kirk
>
> Steve Adeff wrote:
> > On Thursday 13 October 2005 12:50, Kirk Bocek wrote:
> >>Here's the output on my SATA drive:
> >>
> >># hdparm -Tt /dev/sda
> >>
> >>/dev/sda:
> >>  Timing cached reads:   3832 MB in  2.00 seconds = 1915.88 MB/sec
> >>HDIO_DRIVE_CMD(null) (wait for flush complete) failed: Inappropriate
> >> ioctl for device Timing buffered disk reads:  184 MB in  3.02 seconds = 
> >> 60.84 MB/sec HDIO_DRIVE_CMD(null) (wait for flush complete) failed:
> >> Inappropriate ioctl for device
> >>
> >>So it fails on some sort of IO command but still runs the benchmark.
> >>
> >>Kirk
> >
> > those IO errors are normal as hdparm is designed for IDE while the SATA
> > drivers treat SATA as a SCSI device.  from your numbers though, DMA is
> > definitely on.
> >
> > Steve

Well, yes, but the older SATA drivers didn't have a complete command set. I 
used to get the same error on my SATA drives but with the 2.6.13 kernel i 
don't. Nothing to worry about though, and as I said, "DMA" is definitely on 
(not that SATA does the whole DMA thing like PATA does).

Steve