Bring On Holographic Storage


If I needed any more proof that Mondays are a fundamentally evil day, I would look no further than today.

I woke up, staggered blearily down the corridor to the kitchen, and was alerted to an ominous clacking noise emanating from the server closet. As it happens, the matching pair of that Maxtor disk that gave me trouble a few weeks back died sometime in the wee hours of the morning, taking with it my entire bulk archive - my disk image of Xcode 2.4, sets of ISO files for Fedora and Ubuntu, assorted media (fortunately not my MP3 rips), several gigabytes' worth of cartographical data that Bruno had given me when I was toying with the notion of GeoCaching, a bunch of VMware and QEMU images with pre-loaded operating systems, and, of all things, my Quake III Arena snapshot.

Plus, of course, a bunch of other stuff that I am only likely to notice when I go looking for it - that's what I'm really annoyed about. Although I religiously back up my Mac's home directories (which includes most of the freeware stuff I use, which I keep in an Applications folder under my home directory), there's always some PDF or piece of software that I tossed into a network drive and (nearly) forgot about.

Hot Bits

Some of this is, of course, related to the heat. Those Maxtor disks were on 24/7 hooked up to my NSLU2, and since they could not be powered down (or power managed), their plastic casings were always very warm to the touch. Add in the over 40C temperatures outside (which eventually raise indoor temperature quite a bit), and you're bound to have parboiled bits sometime - which is why I eventually started buying disks with fans.

Sure, I could invest in something like an Infrant NAS, and lock it away somewhere I don't have to look at (or listen to) it.

The thing is, a full-blown home NAS isn't something that I'm keen on, since:

  • It will end up being used only for around 10% of the time, or less (even if you're at home all evenings and weekends, you won't be accessing it all the time).
  • It will be noisy, or hot, or (sometimes) both.
  • It will waste power to the point where the electricity bill is likely to be a surprising item in any cost-benefit analysis.
  • The ROI on having advanced features like RAID5 is very hard to justify, even considering the loss I experienced.

So unless there's a box out there that will wake up quickly when accessed via the network and lay quiescent the other 90% of the time it's not really necessary, I'll stick to plugging cheap disks into an NSLU2, with the extra twist of sparing some time to organize things so that the more important stuff is on a powered off drive.

Still, stuff like this is why things like MyLifeBits won't get anywhere soon. Without some sort of cheap, massively dense random-access storage that can lay quiescent until necessary, even home users will soon find themselves with massive amounts of data that they can't easily back up.

The Olden Days

Looking back, this is not a new problem. I used to have an 8" floppy (from a TRS-80 or some forgotten IBM dinosaur, I'm not sure) pinned on my office wall, a relic of days before I discovered CP/M and DOS and 5.25" came along.

And I used several forms of increasingly denser (but always boringly slow) optical storage. I started with 2.5" 20MB optical disks way back when the Mac was 680x0-based (and we shared a "massive" 160MB - yes, MB - disk among several Macs with that funky serial AppleTalk) and eventually progressed to today's dubiously wonderful dual-layered DVDs, with the NeXT's cartridges and other more or less brand-specific formats in between.

All the while, archival/backup media (other than tapes, which I find to be a loathsome and volatile approach) has always fallen somewhat short of the mark, and I don't see this changing anytime soon.

Data Crystals, Anyone?

But regardless of whatever lies ahead in using photons to carve grooves, there's another problem - you can't even easily copy across to other disks. Sure, Firewire is great, but there are practical limits to the number of disks you can daisy-chain to your machine (if only in terms of noise, heat and cable tangles).

And getting back to the NAS approach, when you're using one, the most likely bottleneck is Fast Ethernet's speed - toss in the SMB network protocol overhead, some processing at either end, and you're lucky to reach a sustained throughput of 5MB/s (your mileage may vary, but this is about my average everywhere).

Sure, you can go giga, but... it hasn't really hit mainstream yet - not at the consumer level. Although I'd be hard pressed to find a recent machine without it, there aren't that many small consumer switches out there, and there will always be something running at slower speeds.

Which means that when Auntie Florence's got to back up 50GB of photos of her grandsons, petunias and assorted cats, she's going to have to wait a good while. Or ask her nephew, who will burn a dozen DVDs, or a quarter that number in whatever new thing eventually comes along (I'm not holding my breath regarding either HD-DVD or Blu-Ray).

Or (which is the most sensible thing right now) go out, get another external hard disk and wait an hour or so until the Finder copies things across (if you have Firewire disks, and taking into account its obtuseness regarding massive file copies).

This, incidentally, is where the iLife concept meets reality. iPhoto, iMovie, etc. - all those applications enable people to create, yes. To create gigabytes of data that is increasingly harder to back up in any sensible way, and which is just crying out for some form of permanent storage.