In the November 2007 issue, we took an in-depth look at RAID—short for Redundant Array of Inexpensive (or Independent) Disks—and broke down the pros, cons, and most importantly, speeds of the various RAID permutations you would find on a typical multidrive setup. Here we’ll examine the medium itself: the RAID controller, which tells the drives in a RAID setup how to interact. As you’ll see, there are RAID controllers of differing types, technologies, and price points, and we want to learn whether these variations translate into performance differences. After all, even the fastest RAID configuration ultimately depends on the performance capabilities of its physical host.

A RAID array can be set up in one of two ways: You can use the controller that’s built into your motherboard’s chipset (if it includes one), which requires you to hook up your drives as normal and then edit a few BIOS settings, or purchase an external controller card, which boots its configuration menu before your operating system even loads.

Our mission is to test the performance of RAID setups using both low- and high-end RAID cards from five different manufacturers and compare those results against the performance of two common motherboard solutions. Once the dust settles, you’ll know which RAID controller will give you top performance and exactly what features you get for your buck!

Our Testing Methods

Every aspect of our experiment had to be considered in order to ensure meaningful results.

The Controllers

To test the performance of motherboard-based RAID controllers we turned to Nvidia’s nForce 680i chipset and Intel’s P35 chipset. The former represents the typical testing environment we use for all our storage benchmarking and is a solid example of what you’d find on a high-end motherboard. The Intel-based board provides a fair representation of RAID performance on a midrange machine. Given Intel’s dominance in the performance-computing market right now, we didn’t bother testing an AMD-compatible motherboard. What’s the point?

For our controller cards, we picked a combination of host-based and discrete models: With the former, the controller uses the rig’s processor to handle RAID functionality (just as a motherboard chipset does), while discrete controllers remove your computer from the equation by supporting a low-powered processor right on the card. As you might expect, host-based controllers are cheaper than their discrete counterparts. Besides selecting controllers for both card types, we also sought to vary the price points in each category.

The Test Bed

All the testing, save that done on the MSI P35 Neo2-FR motherboard, was conducted using our standard storage benchmarking system: an Intel Q6700 on an EVGA nForce 680i motherboard, a single EVGA GeForce 8800 GTX videocard, and a single 500GB Western Digital Caviar SE16 hosting the Windows XP operating system. Each RAID test uses four Western Digital 150GB Raptor drives.

We elected to use two RAID configurations for benchmarking: RAID 0 (aka striped) and RAID 5. This allowed us to study the price/performance equation from two different mindsets: speed and redundancy. As we noted in our previous RAID feature, you won’t find a faster storage configuration than RAID 0, in which the drives serve as one volume and your data is written and read across them concurrently. A RAID 5 setup balances the performance gains of striped arrays yet still offers a degree of data redundancy.

The Benchmarks

We’re using the same standard suite of benchmarks we normally use for storage testing, with a few changes. We’ve downgraded our HD Tach program to version 3.0.1.0 to ensure we can run both read and write tests on the arrays. This synthetic benchmark bypasses any software on a machine to get right to the drives themselves, measuring the subject’s

For a more real-world test, we’re using PCMark05. We’ll compare the scores from the program’s subset tests—XP Startup, Application Loading, General Usage, Virus Scanning, and File Writing—as well as the overall score given to each test subject.

Finally, we’ve created our own real-world benchmark to further test these arrays under a typical usage scenario. We time how long it takes to write a 1080p multimedia slideshow to the array using Photodex’s ProShow, based on files read from the array, while simultaneously using Adobe Premiere to convert a DVD rip on the array into an uncompressed AVI file. As these tasks also maximize our processor’s usage, it allows us to discern the potential performance pitfalls of a card that uses said processor for its RAID calculations.

COMMENTS:

0

TAGS: 

motherboards, RAID, raid controllers, features, May, 2008, from the magazine, reviews

Comments Print Email