Convoy 425XL: 4x 500GB Sata on Raid5 extreme low write performance

[Bigf0ot]

Hi,

I bought my Convoy 425XL for my Homeserver (windows 2008 r2) utilising 4x Western Digital WD5000BUDT 500 GB in a Raid5 Set.

I didn't expect overhelming performance, as it is a cheap part of hardware (compared with a good raid controler) and doesn't have any nameable amount of cache, but I atleast expected the performance of an usual onboard Raid Controller.

The read performance is ok, but write is below my worst nightmare!
As my Server, new installed on the Raid5 set, was soo slow,
I made some Tests with IOmeter (glad to share the Logs), and i got 4-5 MB/s writes at 32k Blocks sequential write with 5 outstanding IOs....thats crap!
With 32k Blocksize, every Storage Vendors fakes its Benchmarks :-)
512b blocksize (native Disk Blocksize) i got below 1 MB/s.
A 2T Caviar Green give's you easily 100 MB/s at 32k sequential write...on a single 3,5" Disk!

As i couldn't belive this, i moved it to my PC but the results were exact the same.

I can not imagine anything to change or that i did wrong, as no drivers have to be installed and the Dip switches are not so difficult to handle.
Is there anything I can do or try? Or should i simply use my 14 days giveback right i got here in Germany?

[Patriot_Z]

what board you using?

RAID setting i suppose at RAID 5?

can you check if perofrmance drops on other RAID settings? such as mirror or clone?

but yes.. your IO is reallllly low.

[Bigf0ot]

Hi,
I'm using a MSI H55M-ED55 in the "Homeserver" and a Gigabyte E7AUM-DS2H in the other System.
The RAID Setting is at RAID5, yes.

Will give the other RAID Settings a try this weekend.

Btw, I also obend a support Ticket, the same day i posted this topic...but didn't got any reply yet.

[Bigf0ot]

Hello again,
so i did a coule of tests this weekend and they got all the same result.
But i was also able to identify the root of this "issue" :/

The Performance i monitored on every RAID-Setup was the same and it is exactly the behavior of a single WD5000BUDT without the Convoy 425XL (Even RAID1 or RAID10!)
This is simple logic, as the Convoy 425XL doesn`t have any cache itself, it can not be faster then the slowest Disk it is using.
So, the error is in front of the keyboard :-)

Suggestion: Only use the Convoy 425XL with fast(!!) Disks or SSD's, and only for reasons of redundancy, not performance.

regards

Bigf0ot