RAID 0 HDD too slow?

I have installed 2x 74g 10,000rpm Raptors in RAID 0 with a 64k stripe.

Using Fresh Diagnose I get the following results:

write speed average - 7.25 mb/s
read speed average - 58.23 mb/s

No wthe read speed is faster than the other benchmarks, but the write speed is way behind normal 7200 drives.

What results should I expect? And any ideas why it is so slow?

 

Many 'on board' raid solutions lately are pretty pathetic. You should also try converting it to a software raid and rebenching it, in many cases that will perform a magnitude faster.

Benching raid accurately takes a little more skill than metering a regular disk. You need to make sure the tool you are using isnt doing silly stuff that will cause split I/Os, or unnaturally step over multiple stripes.

 

Strange - I will try earching the boards and googling.

 

Is this a Promise onboard? or a Silicone Image? or a True Hardware controller?

The 3 ware Escalade cards rock but they aint cheap!

 

Hi ssmith10pn,

I use an ASUS P4P800 SE motherboard which has onboard RAID controller.

If onboard RAID controller is not good quality - there is no point in them at all.....I can't imagine it would casue such poor performance as this...

here is a snipit from the ASUS website specs on the P4P800:

ICH5R with Integrated SATA and RAID 0
Intel is the world's first chipset maker to integrate Serial ATA (SATA) and RAID 0, 1 functions into the South Bridge. The latest ICH5R chipset now delivers 150MB/s fast data transfer (SATA) and striping performance to enhance computing efficiency

 

I have donwloaded a few programs to run benchmarks and got totally different results (see below). So I was wondering if anyone here can recommend a good tool or suite of tools for benchmarking hard drives and RAID arrays. I use 3DMark for all my graphics benchmarks, but can't find a program I know works for this.

Results:
RAIDMark Results:
Read - 1.2 mb/sec
Write - 17.72 mb/sec

NBench Results:
Read - 45 mb/sec
Write - 106 mb/sec

CHDDSpeed Results:
Wildly varied results on all tests

FreshDiagnose Results:
Read - 94 mb/sec
Write - 10 mb/sec

I also found a very large file in my Doom3 Directory copied it and pasted it to desktop timing it. That showed a 30 mb/sec speed on average.

As you can see these results vary wildly, so I don't think the tests are working for RAID 0 and the test for RAID arrays (RAIDMark) is also way off the mark even from my basic timing tests.

 

IOMeter can give you some good benchmarks when setup well.

Winbench can do simulated real world traffic, which is desirable.

Perfmon, when used with something like iostress.

There is a lot of information you have to incorperate when you are benching. Especially with raid, there are lots of variables. Theres no point in doing anything other than the winbench simulations unless you have a specific use in mind. A fast seeking disk does not mean that its a good choice for SQL. A big mover is not the thing you want for a file server.

What are you trying to accomplish. What is your intended use? What does your data flow look like. You need to catogorize your desired IOps, your desired bandwidth on sequential operations, and most importantly, you need to understand how your app uses the file system. Is it bursty? Does it cause a lot of platter seeks? Does it plow through sequential reads? Once you have that data, you can pull a benchmark. Without all that information, your just foolin around, and may be collecting data thats not relevant to your application.

 

Are you sure you mean Mb (mega bits) and not MB (mega Bytes)?

the advertised transfer rates of 150 MB (mega bytes) is burst speed and not sustained.


If your array was really doing this: Read - 1.2 mb/sec
Write - 17.72 mb/sec

It would be slow as mollassas just loading windows.

 

Yes I know, that's why I don't think that program worked properly. By mb I did mean bytes - I should have been more careful there

My PC is for home use. It is used for Gaming & online use. Downloading and installing files, often very large files. Basicallay I want fast drive to install and load large games as fast as possible and for fast access/load times for games that have to load huge amounts of textures as seemlessly as possible - such as Doom3 and Half-Life2.