Earlier I've posted some results from a comparison between different ATA RAID setups using Apple's software based solution included in Mac OS X, and a hardware based solution that uses a PCI RAID card. These second more extensive tests follow the same purpose.

As I've been using a PCI RAID card in a RAID 0 setup for years I'm clearly biased towards this solution. This summer when I ordered a G5 I saw the end of my hardware RAID days coming, that's why I conducted these tests: to see if OS X's RAID is a viable alternative to a PCI RAID card.

Let's compare features:

Test setup:
PowerMac G4, dual 1.42 GHz, 2 GB RAM, Radeon 9800 Pro, Mac OS X v10.2.8
Two WD 200 GB 7200 rpm 8 MB cache drives, each attached as Master to an individual channel on an Acard ATA-133 PCI RAID card - in *all* tests. For OS X's RAID and the single disk tests, jumpers on the PCI card were set to non-RAID ("JBOD") mode.

The tests are divided in the following sections:
• Finder file/folder duplication
• Helios LanTest
• Intech's QuickBench
• XBench disk tests
and finally the conclusion.

Finder

In this test, I simply duplicated a large file and a folder with lots of smaller files on the target volume.
Throughput values in MB/s are simply file size divided by time to duplicate, but considering the computer has to read *and* write the file(s) actual read/write performance is about twice that number.

RAID 0 (stripe): As expected, both striped RAID configurations are faster than a single disk, the hardware solution being yet somewhat faster.
RAID 1 (mirror): In the mirrored RAID configuration, the software based RAID is considerably slower than a single disk (especially with a single file), whereas the hardware solution is about as fast as a single disk.

HELIOS LanTest v3.1.0u0318

This test is done using Helios LanTest. I only used the results from the read/write tests (average out of 10 tests). As I selected 'very fast networks' in the Preferences, a 300'000 KB file was used (default is 30'000 KB).

RAID 0 (stripe): The software solution is a little faster than a single drive, the hardware solution is considerably faster.
RAID 1 (mirror): Again, the hardware RAID is about as fast as a single drive, the software RAID considerably slower.

QuickBench X v1.0.1

This test uses QuickBench X v1.0.1. I also conducted the "Extended Test" (which uses filesizes from 2 to 10 MB), but as the results were more of the same, I don't show them here.

RAID 0 (stripe): The software based RAID 0 seems to be a little *slower* than a single disk (!). The hardware RAID 0 once again is considerably faster than a single disk, more so as filesizes grow.
RAID 1 (mirror): The software based RAID 1 takes a hit compared to a single drive, whereas the hardware RAID performas about the same as a single drive (a little faster on writes, and a little slower on reads).

Xbench v1.1.3

This test uses XBench. I only used its disk test.

RAID 0 (stripe): As expected, both striped RAID configurations are faster than a single disk, the hardware solution being somewhat faster.
RAID 1 (mirror): In the mirrored RAID configuration, the software based RAID is considerably slower than a single disk, whereas the hardware RAID is about as fast as a single disk.

Conclusion:

As can be seen, the solution with dedicated RAID PCI card surpasses the software based solution in performance and features, but also in price - following the WYPIWYG principle (what you pay is what you get).
I for one will probably get one of the new Raptor 10K drives to make up for the loss of my RAID 0 in the G5.

Here are a couple of links I thought might be of interest:
It all started in the forum
First comparison tests
Some rather old (OS 9 days) RAID vs non-RAID tests
Extensive Information on RAID in general

Cheers, Oliver AKA boli

(The other advantage of the switched RAID card is that you can boot to OS 9 from the RAID volume, for those that still need/want to boot to OS 9 and have the RAID array usable from other than classic mode.-Mike)

(copy of his first results follow)

Test system: powermac G4, dual 1.42 GHz, 2 GB ram running mac os x 10.2.x (tests were done some time ago, probably was 10.2.6 though).

the harddisks are western digital 200 gb, 7200 rpm, 8 mb cache models (ata-100). Acard ATA/133 RAID IDE card used for all tests, comparing the RAID switch mode vs using OS X's RAID.

Time to duplicate a 457.2 MB file (quake3's pak0.pak):

OS X Software RAID:
23s (equals 19.9 MB/s) with OS X RAID 0 (stripe)
33s (equals 13.9 MB/s) with OS X RAID 1 (mirror)
25s (equals 18.3 MB/s) single disk internal ata-100

Acard ATA-133 PCI RAID card:
14s (equals 32.7 MB/s) with Acard RAID 0 (stripe)
20s (equals 22.9 MB/s) with Acard RAID 1 (mirror)
21s (equals 21.8 MB/s) single disk Acard ata-133

---
results in order of performance (top is faster):
14s (equals 32.7 MB/s) with Acard RAID 0 (stripe)
20s (equals 22.9 MB/s) with Acard RAID 1 (mirror)
21s (equals 21.8 MB/s) single disk Acard ata-133
23s (equals 19.9 MB/s) with OS X RAID 0 (stripe)
25s (equals 18.3 MB/s) single disk internal ata-100
33s (equals 13.9 MB/s) with OS X RAID 1 (mirror)

-------------- Xbench results -----------
If anyone cares, here are a couple of XBench scores of the same setup. I don't trust XBench much generally, but it was what I had around at the time.

OS X RAID 0       128.27
Sequential        132.45
Uncached Write    139.02     60.65 MB/sec (4K blocks)
Uncached Write    158.11     64.33 MB/sec (256K blocks)
Uncached Read     113.39     17.86 MB/sec (4K blocks)
Uncached Read     127.16     54.86 MB/sec (256K blocks)
Random            124.35
Uncached Write    173.12      2.61 MB/sec (4K blocks)
Uncached Write    229.48     52.65 MB/sec (256K blocks)
Uncached Read     105.77      0.69 MB/sec (4K blocks)
Uncached Read      79.5      15.58 MB/sec (256K blocks)

OS X RAID 1        80.05
Sequential         69.81
Uncached Write     64.73     28.24 MB/sec (4K blocks)
Uncached Write     83.21     33.85 MB/sec (256K blocks)
Uncached Read      84.13     13.25 MB/sec (4K blocks)
Uncached Read      55.72     24.04 MB/sec (256K blocks)
Random             93.83
Uncached Write     81.58      1.23 MB/sec (4K blocks)
Uncached Write    131.17     30.09 MB/sec (256K blocks)
Uncached Read     101.03      0.66 MB/sec (4K blocks)
Uncached Read      77.8      15.25 MB/sec (256K blocks)

Single Drive      100.33 (on internal ATA-100)
Sequential         94.23
Uncached Write     84.81     37.00 MB/sec (4K blocks)
Uncached Write    125.65     51.12 MB/sec (256K blocks)
Uncached Read     150.58     23.72 MB/sec (4K blocks)
Uncached Read      62.27     26.86 MB/sec (256K blocks)
Random            107.27
Uncached Write     87.96      1.33 MB/sec (4K blocks)
Uncached Write    124.22     28.50 MB/sec (256K blocks)
Uncached Read     103.55      0.67 MB/sec (4K blocks)
Uncached Read     121.73     23.86 MB/sec (256K blocks)

Acard RAID 0      147.63
Sequential        159.6
Uncached Write    139.6      60.91 MB/sec (4K blocks)
Uncached Write    224.54     91.35 MB/sec (256K blocks)
Uncached Read     131.43     20.70 MB/sec (4K blocks)
Uncached Read     171.33     73.91 MB/sec (256K blocks)
Random            137.33
Uncached Write    182.0       2.75 MB/sec (4K blocks)
Uncached Write    158.68     36.40 MB/sec (256K blocks)
Uncached Read     105.64      0.69 MB/sec (4K blocks)
Uncached Read     127.16     24.92 MB/sec (256K blocks)
          
Acard RAID 1      109.18
Sequential        116.96
Uncached Write     95.58     41.70 MB/sec (4K blocks)
Uncached Write    123.65     50.30 MB/sec (256K blocks)
Uncached Read     138.21     21.77 MB/sec (4K blocks)
Uncached Read     118.83     51.26 MB/sec (256K blocks)
Random            102.38
Uncached Write     82.82      1.25 MB/sec (4K blocks)
Uncached Write    114.22     26.20 MB/sec (256K blocks)
Uncached Read     101.33      0.66 MB/sec (4K blocks)
Uncached Read     119.44     23.41 MB/sec (256K blocks)

Single Drive      114.58 (on Acard)
Sequential        126.16
Uncached Write    111.57     48.68 MB/sec (4K blocks)
Uncached Write    141.02     57.37 MB/sec (256K blocks)
Uncached Read     138.3      21.78 MB/sec (4K blocks)
Uncached Read     118.77     51.24 MB/sec (256K blocks)
Random            104.94
Uncached Write     87.4       1.32 MB/sec (4K blocks)
Uncached Write    115.5      26.50 MB/sec (256K blocks)
Uncached Read     103.39      0.67 MB/sec (4K blocks)
Uncached Read     119.82     23.49 MB/sec (256K blocks)

---
results in order of performance (top is faster):
Acard PCI ATA-133 RAID 0 147.63
OS X RAID 0 128.27
Single Drive on Acard PCI ATA-133 114.58
Acard PCI ATA-133 RAID 1 109.18
Single Drive on internal ATA-100 100.33
OS X RAID 1 80.05

-Oliver B.