[mythtv-users] Slow video on XFS raid 0, ok video on ext3 on single drive.

[Andrew Lyon]

On 12/30/06, Listbox <listbox at hymerfania.com> wrote:
> Hi folks!
>
> I have two Seagate 160gb drives in a RAID 0 array on an SiI0680 PCI ATA raid
> controller. I formatted an XFS filesystem on a single partition, and set
> mythbackend to use it. My DVB card is a DviCO Fusion Gold 3,( Conexant
> CX23880).
>
> When I watch live TV, I get terrible artifacts on digital TV, and slow frame
> rates on analog. When I reset mythbackend to use a ext3 partition on a
> single drive, performance is acceptable.
>
> I went to considerable trouble to get the RAID and XFS working on my Fedora
> 5 system, and it's pretty discouraging to see that it actually degrades
> instead of enhances performance. What is likely the problem? Is it the
> controller, the raid or the filesystem?
>
> Thanks for any advice!
>
> Listbox
>
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Please use hdparm -tT to benchmark the speed of your drives, and your
raid array, e.g.

hdparm -tT /dev/sda /dev/sdb /dev/sdc /dev/md0

You should do this when the system is idle, perhaps even in single user mode.

That should shed some light on the situation.

Andy