ata133 raid in linux with promise pdc20269 maxtor controller

[phrawd]

This topic could go in a lot of the forums but I figured that any solution would work for windows but it would take that extra bit to get it to work in linux so I chose this one... Anyhow, I have an IWILL kk266-r with the on board raid controller. However, this raid controller is udma and I'd like to take advantage of the udma133 on these drives, despite many saying there is no real world performance difference. I have a promise ata 133 hard disk controller (the one packaged with a maxtor retail -- promise chip #pdc20269). Is there any way to set up the raid so that it uses these controllers and udma 133 even though the board only supports udma 100? I'm a bit stumped...

Regards,

Marshall

 

[Nothinman]

However, this raid controller is udma and I'd like to take advantage of the udma133 on these drives, despite many saying there is no real world performance difference

DMA itself helps, as opposed to PIO which uses a lot more CPU cycles, but the 133 part isn't very important. It may be easier just to enable DMA on the ATA/33 controller.

If you try to push a drive into a UDMA mode it doesn't support you'll likely only get corrupt data, don't do it.

Either way you'll probably have to recompile your kernel to support the card, I've not watched the Linux-ide world closely lately since I'm all SCSI, sorry I can't be more specific.

 

[manly]

RAID on two distinct ATA/100 channels will perform better than a single drive on ATA/133. The *best* IDE hard drives currently push 50+ MB/s peak throughput, so a single drive doesn't really even saturate ATA/66. So there is no real-world performance difference between the specs.

Of course, any onboard IDE RAID is really just software RAID but that's still faster than ATA/133.

To answer your question, you likely can get ATA/133 support under Linux for an add-on controller. However, the onboard IDE (software) RAID is still based on the default ATA/100 channels; there's no mix and match. However, you could run Linux's software RAID with hard drives attached to the add-on ATA/133 controller if you really wanted to.