ben robison

RAID Options for Mac OS X

If you’re anything like me, you often daydream of the wonderful computer setup you’d like to have someday if you can ever afford it. All those computers & gadgets, working flawlessly together in absolute technological bliss.

Well, as I near graduation, my probably false perception, is that those dreams are a little closer. The first two items on that imaginary shopping list is some kind of RAID storage solution and some kind of device that plays all my content on my TV (and since my TV is old, analog, crt, and several hundred pounds, I better throw in a new one of those as well).

Plasma vs. LCD, AppleTV vs. Netgear’s Digital Entertainer vs. the upcoming SlingCatcher are debates that can wait. I’d like to express my dilemma regarding the various RAID options I’ve investigated.

Hardware vs. Software
For me, the obvious option is hardware RAID. For one, it’s faster. I’m a firm believer that if something can be handled at the hardware level, it can be done quicker and with less overhead than a similar function implemented as a software solution (assuming the respective developers know what they’re doing). I’ve read claims of software RAID solutions that are just as fast or faster than hardware solutions, but in my eyes, it simply doesn’t hold water.

Another reason is it’s movable (I was going to say mobile, but that just doesn’t fit). There’s only one Mac in my life at the moment, but I hope to see that number increase in the future. That being said, I still have Windows & Linux machines in my apartment. The idea of all my data being tied to a specific OS makes me shudder. Hardware solutions can be moved.

Internal vs. External
Given the choice, I’d like to stay internal, but I can be flexible on this. My computer space has enough cables and external enclosures lying around that one more little enclosure of some kind wouldn’t be too much of a hassle.

Windows vs. Linux vs. Mac
Awhile ago, I specced a system for my father-in-law, building my own server from the ground up. I think I’ve learned a little since then, but the price for the pimped out almost 1TB RAID server (4 x 320 G drives & a 3Ware controller) was $2700. If I put Windows on it, then you can add the cost of Vista or Windows Server. So for cost of OS purposes, we’ll just round up to an even $3k.

What about the Linux option? That would keep the price at around $2.7k, but I’ve looked into a few different distros and I can’t say with any amount of confidence that I could even find a distro that could support the RAID controller. If you’re not doing software RAID on your Linux machine, it’s a complete tossup if you can get drivers to support your setup.

What about the Mac possibilities? Not encouraging. Until recently, the only solution I could find that I would call even close to reliable was the XServe RAID. If you’re thinking of going that route, your looking at $6k on the low-end, plus whatever you plan on plugging it into (XServe starts at $3k, Mac Pro starts at $2.5k). Don’t get me wrong, I’d love to have a gleaming XServe sitting just above my XServe RAID in a rack in the closet, but it seems a bit expensive.

Enter the 3Ware Sidecar. It’s external and still expensive, but it does have style and it’s coming much closer to the affordable mark. It retails for $1295 which does not include the cost of the SATA II drives you can put in it. 4 x 320 G drives in a RAID 5 array gives you close to 1TB of space tagging on another $360. The price includes the cost of the actual PCI-E hardware controller, but does not include the required G5 or Mac Pro. Again, the low-end Mac Pro tags another $2.5k, so we’re now looking at just over $4.5k for your Mac Solution.

So do the benefits of having a Mac Pro in your house outweigh the extra $1500? I know a lot of people who would say yes. Depending on the amount of my disposable income, I might be inclined to agree with them. There’s a lot you can do with that kind of power. Maybe the perfect solution would be to get the guys over at 3Ware to market the card separate from the SideCar, then you could just toss the drives into your Mac Pro and save all the extra cost of the enclosure and the required cabling.

*** Update: I dug a little further and discovered that the 3ware sidecar is also compatible with the Powermac G5. Those are selling on eBay in the $700-800 range. That would bring the Mac solution down into the $2.5k range making it the cheapest hardware option.

However, I then had to ask if a Powermac G5 would really be getting the benefits of hardware RAID and I think the obvious answer is no. Which begged the next question: if nearly every hit on this so-called media server is happening over a network through SMB or NFS, would any machine really see the speed benefits of hardware RAID? Again, the obvious answer is no.

Now the most important question of all: if you’re not going to see the speed benefit, is forking over all that extra cash really worth the benefit of having mobility? I’m not sure it is, which suddenly makes software RAID a viable option. Macs can do software RAID out of the box. For the cost of a Powermac G5 + Sidecar, I could buy a Mac Pro!

*** Update 2: After looking into transfer speeds of network file sharing protocols (9-30 MB/s for Samba and NFS) and the RAID speeds available in hardware RAID (600-700 MB/s for 3ware 9650), my arguments for speed are likely useless anyway.