[CentOS] Re: DMA mode

David Mackintosh wrote:

Hi folks,

I have an HP Proliant 140DL G2 server with what appears to be an IDE drive in non-DMA mode. Performance on the server is extremely bad when large amounts of disk activity is taking place.

I think the problem is that my drive is not in DMA mode:

# hdparm /dev/hda

This should be /dev/sda and not /dev/hda which means you're most likely using the generic-ide driver and not ata-piix.

Google suggests booting with ide0=noprobe ide1=noprobe to make sure the ata-piix driver is used. If you don't want to reinstall then make sure initrd contains the ata-piix driver and that references to /dev/hd* are replaced with /dev/sd* in fstab etc.

-tgc