Re: Software RAID problems (bad filesystem type)

[Justin Guerin <jguerin@cso.atmel.com>]

Hi Timo.

On Wednesday 18 February 2004 08:19, Timo Railo wrote:
> Thanks Benedict,
>
> this is what happened (also tried just -d1).
>
> hdparm -d 1 -c 1 /dev/hda
>
> /dev/hda:
>   setting 32-bit IO_support flag to 1
>   setting using_dma to 1 (on)
>   HDIO_SET_DMA failed: Operation not permitted
>   IO_support   =  1 (32-bit)
>   using_dma    =  0 (off)
>
> Man this is tough...
>
> Timo
>
Looking at the man page for hdparm, it's possible your drive doesn't support 
that operation (-d).  You might google with the name of your drive, to see 
if it's a known issue.  Have you also tried "hdparm -d 1 -X34 /dev/hda"?  I 
wonder if that would help.  

For what it's worth, my RAID-1 performance was quite different from yours:
# hdparm -Tt /dev/hda /dev/hdc /dev/md1

/dev/hda:
 Timing buffer-cache reads:   128 MB in  1.02 seconds =125.49 MB/sec
 Timing buffered disk reads:  64 MB in  3.01 seconds = 21.26 MB/sec

/dev/hdc:
 Timing buffer-cache reads:   128 MB in  1.11 seconds =115.32 MB/sec
 Timing buffered disk reads:  64 MB in  2.93 seconds = 21.84 MB/sec

/dev/md1:
 Timing buffer-cache reads:   128 MB in  1.09 seconds =117.43 MB/sec
 Timing buffered disk reads:  64 MB in  3.01 seconds = 21.26 MB/sec

My disks are operating in udma2 mode.  
Justin