Integrated RAID chips

Abbo

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Feb 15, 2003
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There are lots of components that have been integrated into motherbords to reduce costs, such as modems, NICs and sound cards. It´s also known that almost all of this integrated components use HSP processors, so most of their workload is handled by the CPU.
OK, my Duron 700 is powerfull enough to give away a few clock cycles for this kind of integrated components.
But how about integrated RAID chips? Is it the same way?
I don´t think so, because handling that kind of Mb/s would kill my CPU. Heck, it should kill Deep Blue too !!!
So I believe that integrated RAID chips must have a dedicated processor, so that the CPU performance is not degraded.
Maybe some of you have tried integrated RAID chips solutions. So I´d like to know how much workload integrated RAID chips put on the CPU, and wheter their perfomance is comparable to the add-on PCI RAID cards.
By the way, I have a Gigabyte 7ZX-R rev 1.0 motherboard, with an integrated Promise PDC20265R ATA100 RAID chip. Any commnets you may want to post about this particular mobo/RAID chip regarding this issue will be more than welcomed.
 

elzt

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May 10, 2002
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The performance difference between the integrated solutions and the add-on cards is negligible. As for the workload they put on the CPU, I think it's minimal as hardware RAID has its own dedicated controller for performing the stripping or mirroring.
 

lhgpoobaa

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Dec 31, 2007
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yes thats right. the raid chip does most of the hard work,

<i>"Revenues were less than robust"</i> - QWEST
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sjonnie

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Oct 26, 2001
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Most integral RAID chips and most PCI cards you buy support only RAID modes 0 and 1 or a combination thereof. These chips consists of a souped up IDE controller, in fact, you can easily hardwire an IDE controller to function as a RAID0 or RAID1 controller. The burden on the CPU is not significantly higher than when writing to a hard disk via a normal IDE controller.

Recently the HPT374 chips have been changed to give you the possibility of creating a RAID5 array. In this case the XOR parity calculations will be carried out entirely by the CPU, pretty much the same as if you had created a software RAID5 array in Win2K Server. A hardware RAID5 card contains its own processor to do parity calculations, hence the cost of these cards.


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