Running iMac 2009 on an External Drive with 2 SSDs configured in RAID 0 on Firewire

[Riverrun]

I wanted to boost my iMac's performance and so I bought one of these:
http://eshop.macsales.com/item/Other World Computing/MEQMHSSD240/

I transferred the OS to it (clean install) and wiped the Macintosh HD which I now use to store my media files. Documents are kept in the ~ folder on the SSD RAID.

Here are the benchmarks if anyone care to look at them:

 

[Riverrun]

I think that they work better like this:

Before

Results 121.16

System Info
Xbench Version 1.3
System Version 10.7.2 (11C74)
Physical RAM 8192 MB
Model iMac10,1
Drive Type Hitachi HDT721050SLA360

CPU Test 211.62
GCD Loop 349.55 18.43 Mops/sec
Floating Point Basic 169.18 4.02 Gflop/sec
vecLib FFT 142.71 4.71 Gflop/sec
Floating Point Library 320.19 55.75 Mops/sec

Memory Test 211.33
System 286.05
Allocate 1618.34 5.94 Malloc/sec
Fill 192.86 9377.43 MB/sec
Copy 213.46 4408.98 MB/sec
Stream 167.56
Copy 161.25 3330.55 MB/sec
Scale 158.34 3271.29 MB/sec
Add 175.93 3747.70 MB/sec
Triad 176.34 3772.42 MB/sec

Quartz Graphics Test 282.91
Line 263.91 17.57 Klines/sec [50% alpha]
Rectangle 350.65 104.69 Krects/sec [50% alpha]
Circle 272.34 22.20 Kcircles/sec [50% alpha]
Bezier 254.95 6.43 Kbeziers/sec [50% alpha]
Text 290.86 18.19 Kchars/sec

OpenGL Graphics Test 139.59
Spinning Squares 139.59 177.08 frames/sec

User Interface Test 89.85
Elements 89.85 412.36 refresh/sec

Disk Test 54.84
Sequential 100.97
Uncached Write 164.35 100.91 MB/sec [4K blocks]
Uncached Write 58.64 33.18 MB/sec [256K blocks]
Uncached Read 85.43 25.00 MB/sec [4K blocks]
Uncached Read 209.62 105.35 MB/sec [256K blocks]
Random 37.65
Uncached Write 11.96 1.27 MB/sec [4K blocks]
Uncached Write 158.84 50.85 MB/sec [256K blocks]
Uncached Read 95.87 0.68 MB/sec [4K blocks]
Uncached Read 168.94 31.35 MB/sec [256K blocks]

After

Results 163.35

System Info
Xbench Version 1.3
System Version 10.7.2 (11C74)
Physical RAM 8192 MB
Model iMac10,1
Drive Type Mercury Elite Pro Dual m

CPU Test 203.75
GCD Loop 355.71 18.75 Mops/sec
Floating Point Basic 174.03 4.14 Gflop/sec
vecLib FFT 125.78 4.15 Gflop/sec
Floating Point Library 320.12 55.74 Mops/sec

Memory Test 210.40
System 284.54
Allocate 1631.96 5.99 Malloc/sec
Fill 191.01 9287.29 MB/sec
Copy 212.99 4399.13 MB/sec
Stream 166.91
Copy 160.22 3309.20 MB/sec
Scale 157.15 3246.76 MB/sec
Add 175.73 3743.52 MB/sec
Triad 176.37 3772.99 MB/sec

Quartz Graphics Test 274.50
Line 246.06 16.38 Klines/sec [50% alpha]
Rectangle 341.71 102.02 Krects/sec [50% alpha]
Circle 263.67 21.49 Kcircles/sec [50% alpha]
Bezier 260.57 6.57 Kbeziers/sec [50% alpha]
Text 278.24 17.41 Kchars/sec
OpenGL Graphics Test 141.18
Spinning Squares 141.18 179.09 frames/sec
User Interface Test 94.67
Elements 94.67 434.49 refresh/sec

Disk Test 173.00

Sequential 118.62
Uncached Write 160.51 98.55 MB/sec [4K blocks]
Uncached Write 136.35 77.15 MB/sec [256K blocks]
Uncached Read 71.73 20.99 MB/sec [4K blocks]
Uncached Read 160.88 80.86 MB/sec [256K blocks]

Random 319.50
Uncached Write 170.82 18.08 MB/sec [4K blocks]
Uncached Write 256.62 82.15 MB/sec [256K blocks]
Uncached Read 2073.16 14.69 MB/sec [4K blocks]
Uncached Read 437.43 81.17 MB/sec [256K blocks]

 

[Riverrun]

I didn't want to open such a pretty machine and replace the Optical Drive, though I have a compatible enclosure and that is still an option. I did my research well and decided against using the caddy as I thought that the fans might be a little difficult to control. Word is that Apple have booby trapped them and while there are solutions, I felt that the risks were too great. This is an area in which I have choices and I may change my mind!

The firewire 800 bottleneck is throttling back the SSD but I was expecting this. Performance is noticeably faster in the areas of launching apps, copying and pasting (using the Mac Services Menu in combination with TextEdit or Bean for example) and the setup is very stable. It's been up for 3 days now and no adverse effects are visible so far. I can always restore if things go wrong.

The OWC external is a miracle of engineering; no fans and yet it remains cool to the touch and mostly silent to the ear. It does whistle once in awhile but stops in a short time.

I'd be interested in reading about other people's experiences with similar setups and any comments that you wish to make about the benchmarks.

Geekbench, which measures CPU efficiency returned a small gain which surprised me but as I say it was a matter of a score or so points and not significant.