Testbed and Methods
The following benchmarks were used:
- IOMeter 2003.02.15
- WinBench 99 2.0
- FC-Test 1.0
- Intel SC5200 system case
- Intel SE7520BD2 mainboard
- Two Intel Xeon 2.8GHz CPUs with 800MHz FSB
- 2 x 512MB PC3200 ECC Registered DDR SDRAM
- IBM DTLA-307015 hard disk drive as system disk (15GB)
- Onboard ATI Rage XL graphics controller
- Windows 2000 Professional with Service Pack 4
The controller was installed into the mainboard’s PCI-Express x8 slot. We used Fujitsu MBA3073RC hard disk drives for this test session. They were installed into the standard boxes of the SC5200 system case and fastened with four screws at the bottom. The controller was tested with four and eight HDDs in the following modes:
- Degraded RAID10 with one failed HDD
- Degraded RAID5 with one failed HDD
- Degraded RAID6 with one failed HDD
- Degraded RAID6 with two failed HDDs
A four-disk RAID6 is not present because 3ware blocks the opportunity to build such an array in the BIOS and driver. We don’t like the developer’s position on this point. On one hand, it is clear that a four-disk RAID10 is going to be faster while delivering the same useful capacity. But on the other hand, a four-disk RAID10 offers lower fault tolerance than a four-disk RAID6. A four-disk RAID10 can only survive a failure of two disks if these disks belong to the different mirrors whereas a four-disk RAID6 is free from this limitation and can survive a failure of any two disks. It would be good if the user had the choice between maximum fault tolerance and speed.
As we try to cover all possible array types, we will publish the results of degraded arrays. A degraded array is a redundant array in which one or more disks (depending on the array type) have failed but the array still stores data and performs its duties.
For comparison’s sake, we publish the results of a single Fujitsu MBA3073RC hard disk on an LSI SAS3041E-R controller as a kind of a reference point. We want to note that this combination of the HDD and controller has one problem: its speed of writing in FC-Test is very low.
We used the latest BIOS available at the manufacturer’s website for the controller and installed the latest drivers. The BIOS and driver pack was version 9.5.1.