RAID0 Performance on an older MB

sdrac

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Sorry if this is similiar to another recent post, but I'm trying to understand if my RAID0 performance is typcial for an older system or if it seems slow - and if the later, if there's anything I can do about it.

Here's my system specs (relevant pieces anyway):
ASUS A8V Deluxe
(sports a Promise PDC20378 RAID controller which I'm using for my
RAID0 array)
A64 FX-60 (not overclocked)
1GB DDR PC3200
Two WD Raptor 74GB Sata150 drives in the RAID array

At any rate, with Sandra i see rates of about 73MB/sec. With HD Tach I see rates between 83MB/sec and 93MB/sec, average of about 84MB/sec and burst rates of 103 MB/sec. It also shows a random access time of 8.1msec and cpu utilization of between 1 and 2 percent.

The rates seem low to me for Raptors in a raid0. Does anyone know if there are limitations with the Promise that may be the cause (or anything else on this MB)? Any suggestions for how to go about improving this
(and don't say get a new MB please!).

Thx,
Sdrac
 

SomeJoe7777

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Apr 14, 2006
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On this motherboard, the Promise controller is on the PCI bus. PCI has a maximum theoretical transfer rate of 133 MB/sec. Once overhead in bus arbitration and transfers is taken into account, maximum real-world transfer rates you'll see on the best designed motherboards is about 120 MB/sec.

VIA chipsets have notoriously poor PCI performance, and 90-100 MB/sec maximum is common.

You're doing the maximum you can with this motherboard/chipset.
 

sdrac

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SomeJoe -
Thanks!
At least I'm doing the best that can be done with this setup.
Thanks again.
Sdrac [/quote]
 

Madwand

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From what I see, that board also has on-board VIA RAID that doesn't go through PCI.

http://techreport.com/reviews/2004q3/asus-a8vdeluxe/index.x?pg=3

IMO that would be worth trying (presuming that it's not too much of a hassle to backup the data elsewhere, re-build the RAID and restore the data). I've seen around 140 MB/s read/write on another board with a VT8237 south-bridge with two non-Raptor drives in RAID 0. I used 32k stripe size for those tests.
 

sdrac

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Madwand,
Thanks for the tip.
I have been backing up the array to a 160MB Maxtor - but I have never actualy tried to restore a system this way before (figured I'd figure it out if/when I had a drive crash and needed to do it). Any ideas on how difficult this is in practice?
I noticed from the url you sent that the cpu utlilzation using the VIA chip seems to go up. The review downplays it, but I wonder if thats anything to worry about?
Anyway, thanks again for the tip. I'm thinking of giving this a try despite the two items above.

Sdrac