OS drives on own controller vs being on same controller with data raid5 array (performance?)

Can anyone comment on whether there would be any real advantage of
having the OS drives (mirror) attached to say the motherboard
controller (SataII), vs being on the same card as say a 3ware 8 port
PCI-x or pcie controller card (along with the raid 5 data array).

IE: when i send backup data to this raid5 array, will it perform
slower if the OS drives are on the same controller?

I cant imagine that it would be that aweful.

I've seen the raid5 benches with HD Tach coming in around 90-120 MB/s
on the raid5 before (cant remember exactly), so would having them over
on the motherboard increase these figures?

Cheers

"markm75" <markm75c@msn.com> wrote in message news:1183142952.674307.200530@m36g2000hse.googlegr oups.com
> Can anyone comment on whether there would be any real advantage of
> having the OS drives (mirror) attached to say the motherboard
> controller (SataII), vs being on the same card as say a 3ware 8 port
> PCI-x or pcie controller card (along with the raid 5 data array).
>
> IE: when i send backup data to this raid5 array, will it perform
> slower if the OS drives are on the same controller?
>
> I cant imagine that it would be that aweful.
>
> I've seen the raid5 benches with HD Tach coming in around 90-120 MB/s
> on the raid5 before (cant remember exactly), so would having them over
> on the motherboard increase these figures?

You already know the answer to that.
Either that or you didn't understand a hoot about the answers to your
earlier PCIe vs PCI-X question.

Just another of your troll attempts, MarkM?

>
> Cheers

Previously markm75 <markm75c@msn.com> wrote:
> Can anyone comment on whether there would be any real advantage of
> having the OS drives (mirror) attached to say the motherboard
> controller (SataII), vs being on the same card as say a 3ware 8 port
> PCI-x or pcie controller card (along with the raid 5 data array).

I don't see any. Unless the hardware is hard to get to
and the controller breaks.

> IE: when i send backup data to this raid5 array, will it perform
> slower if the OS drives are on the same controller?

Depends.

> I cant imagine that it would be that aweful.

> I've seen the raid5 benches with HD Tach coming in around 90-120 MB/s
> on the raid5 before (cant remember exactly), so would having them over
> on the motherboard increase these figures?

The only real way to find out is to try.

Arno

"markm75" <markm75c@msn.com> wrote in message
news:1183142952.674307.200530@m36g2000hse.googlegr oups.com...
> Can anyone comment on whether there would be any real advantage of
> having the OS drives (mirror) attached to say the motherboard
> controller (SataII), vs being on the same card as say a 3ware 8 port
> PCI-x or pcie controller card (along with the raid 5 data array).
>
> IE: when i send backup data to this raid5 array, will it perform
> slower if the OS drives are on the same controller?

We just make sure the OS is not on the same physical disk and the backup
disk system. If this is a backup disk-to-disk system, do you need RAID?

We figure the data is on the production server and it's on the tape (we do
disk-to-disk-to-tape), so if the backup server has a disk problem we still
have the production server and the tape.