Poor Raid 0 performance.....

[daction]

Hey all,

I just purchased a couple new Seagate Barracuda ATA IV's, 40gb a piece, and installed them in my Epox 8K7A+ system. I installed them each on there own Raid IDE channel and ATA100 cable. I then Fdisked the array, about 76gb total size, into one partition. Then formatted, which took a LONG time it seemed, like 2 hours+. Anyway then after installing Windows ME on the array everything seems fine, it's detected in windows as a 75gb drive and all seems well, seems faster than a single drive for sure. Also to mention I installed all the drivers for the MB, the miniport, the 4in1's except agp part, and the Highpoint 370a Raid driver.

So I go ahead and try some benchmarks to see what I get. In sisoft, the score was only slightly higher than a single ATA100 drive, and much lower than there Raid ATA100 setup showed. In HDtach, I get peak transfer rates lower than 35mb/s, and even my new 60gig Seagate drive gets 39 or more. Also in Winbench, my diskmark and inspection test for the 2 40's Raid is about same if not lower than the single 60gig. Overall the raid array is getting performance about the same or less than a single drive, so to say the least I'm disappointed so far. I hope I'm doing something wrong.

Oh one more important thing I noticed was when I went back into the Raid bios, and checked the status of the array, it listed one of the drives as HDD-0, and the other as hidden. This struck me as a little weird but I just figured it has something to do with making them look like one drive, but maybe not.

So ANY help or advice on how to get this Raid setup running like it should, is greatly appreciated.

[daction]

Also another thing I'm not sure of, are you supposed to format each drive individually or both together?

[YODA74]

daction welcome to PC forum, we not getting down on ya for the double post
it's just that a lot of people have questions to. and every one tries to do the best that they can.And when ya double post that means some body else
gets bumped ? Some one will get to each and every question eventually.just hang loose. I do not know any thing about RAID so sit tight. http://www.PCGuide.com/ubb/wink.gif

[daction]

Cool thnx Yoda.

[Dinosaur]

Raid 0 results in increased latency time if the disks are not synchronized. It gets worse if you have 3 disks instead of two.

I am not sure, but I strongly suspect that RAID 0 could be badly impacted by fragmentation. You might have to defrag more often. With one huge drive, head positioning can be costly in addition to the extra latency time due to RAID 0.

Raid 0 is best for applications that deal with huge files and large amounts of data being transferred with each I/O operation. When a small amount of data is transferred per I/O order, the increased latency time costs a lot.

I suspect that it might require special software to take advantage of RAID 0 architecture, but I do not know about this.

Putting the OS & applications on one drive and data on the other can work out better than RAID 0. I run a system with 3 physical disks. I have the OS and applications on one, data files on the second, and the swap file on the third disk(which I also use for data backup). With two disks, I am not sure where it is better to put the swap file: With the data or with the OS & applications.

Depending on how you use your system, partitioning can cut down on latency and head positioning time, which are expensive(They measured in milliseconds).

For most ordinary applications, RAID 0 is a bad idea.

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