[PLUG] A poorly-performing hard drive

[phillip]

That leads me to a question...

I'm running Gentoo with 2.6.0 kernel, and doing this:

hdparm -d1 /dev/hda

gives me this:

/dev/hda:
 setting using_dma to 1 (on)
 HDIO_SET_DMA failed: Operation not permitted
 using_dma    =  0 (off)

and only in linux does it do this....in windows DMA mode works, so i don't 
understand why it won't let me enable it....maybe i should emerge the latest 
hdparm or something?


On Friday 23 January 2004 6:25 am, Rogan Creswick wrote:
> On Thu, Jan 22, 2004 at 09:22:19PM -0800, Evan Heidtmann wrote:
> > # hdparm -tT /dev/hdb
> >
> > /dev/hdb:
> >  Timing buffer-cache reads:   1568 MB in  2.00 seconds = 784.00 MB/sec
> >  Timing buffered disk reads:   22 MB in  3.25 seconds =   6.77 MB/sec
>
> Have you enabled any features with hdparm? This is frequently the
> cause of poor performance (at least in my experience).
>
> run hdparm on the drive w/out any flags, you should get something like
> this:
>
> -($) hdparm /dev/hde
>
> /dev/hde:
>  multcount    = 16 (on)
>  IO_support   =  3 (32-bit w/sync)
>  unmaskirq    =  0 (off)
>  using_dma    =  1 (on)
>  keepsettings =  0 (off)
>  readonly     =  0 (off)
>  readahead    =  8 (on)
>  geometry     = 23989/16/63, sectors = 156301488, start = 0
>
>
> This is a good article on the subject:
>
> http://linux.oreillynet.com/pub/a/linux/2000/06/29/hdparm.html
>
> and here are the switches I use (on an 80gig DMA-100 baracuda):
>
> /sbin/hdparm -m16 -c3 -d1 /dev/hde
>
>
>
> -Rogan
>
> > I was expecting the second number to be over 20MB/s, because my old 15G
> > produces around 18 MB/s. What does this mean?
> >
> > Evan
> >
> >
> > _______________________________________________
> > PLUG mailing list
> > PLUG at lists.pdxlinux.org
> > http://lists.pdxlinux.org/mailman/listinfo/plug
>
> _______________________________________________
> PLUG mailing list
> PLUG at lists.pdxlinux.org
> http://lists.pdxlinux.org/mailman/listinfo/plug