Re: 2.6.20-rc2+: CFQ halving disk throughput.

[Mark Lord]

Tejun Heo wrote:
> Mark Lord wrote:
>
> > > Support for IDENTIFY PACKET DEVICE would be nice too.
> > It already does that, using HDIO_DRIVE_CMD to retrieve it
> > in the same way as for regular IDENTIFY DEVICE commands.
>
> Hmmm... My hdparm doesn't seem to do that.

Sure it does.
Try "strace hdparm -I /dev/sr0" and notice the two ioctl() calls.

The problem is that libata/SCSI always fail it for some reason.
Ditto for me right now when I tried it with an SG_IO passthru command.

Contrary to my other posting, I actually *do* have a libata-controlled
DVD/RW drive in my box here.  So I'll try and see what's happening.

Still digging..
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/