Aug 2008

Solid State Society

The traditional hard disk that’s likely to be in your computer right now is made out of a few magnetic circular platters, with a head attached to an actuator arm above the platter that reads and writes the data to it. The head’s such a microscopic distance away from the platter that it’s equivalent to a Boeing 747 flying at 600 miles per hour about six inches off the ground. So, when you next have a hard disk crash (and that’s when, not if), be amazed that the pilot in the 747 flying six inches off the ground didn’t crash earlier.

Enter solid-state drives (SSDs). Unlike hard disks, SSDs contain no moving parts, and are made out of solid-state memory instead. This has two big advantages: first, SSDs don’t crash (although this is a small lie—more on that later). Second, since SSDs are made out of memory, it’s much faster than a hard disk to get to a particular piece of data on the disk. In other words, they have a random access time that are orders of magnitude faster than their magnetic cousins. Hard disks need to wait for the platter to rotate around before the head can read the data off the drive; SSDs simply fetch the data directly from a memory column & row. In modern desktop computers, random access I/O is often the main performance bottleneck, so if you can speed that up an order of magnitude, you could potentially make things a lot faster.

Unfortunately, while SSDs are orders of magnitude faster than a hard disk for random access, they’re also an order of magnitude more expensive. That was until May this year, when this thing appeared on the scene:



(Image courtesy of itechnews.net.)

That boring-looking black box is a 120GB Super Talent Masterdrive MX. As far as SSD drives go, the Masterdrive MX is not particularly remarkable for its performance: it has a sustained write speed of just 40MB per second, which is a lot lower than many other SSDs and typical hard disks.

However, it’s a lot cheaper than most other SSDs: the 120GB drive is USD$699. That’s not exactly cheap (you could easily get a whopping two terabytes of data if you spent that money on hard disks), but it’s cheap enough that people with more dollars than sense might just go buy it… people like me, for instance. I’ve had that SSD sitting in my lovely 17” MacBook Pro for the past two months, as an experiment with solid-state drives. So, how’d it go?

I’ll spare you the benchmarks: if you’re interested in the raw numbers, there are a number of decent Masterdrive MX reviews floating around the Web now. I was more interested in the subjective performance of the drive. Does it feel faster for everyday tasks? Is it simply a better experience?

The overall answer is: yes, it’s better, but it’s not so much better that I’d buy the SSD again if I could go back in time. With a hard disk, things occasionally get slow. I’m sure I’m not the only one to witness the Spinning Beachball of Death while I wait 5-10 seconds for the hard disk to finally deliver the I/O operations to the programs that want them completed. With a hard disk, launching a program from the dock would sometimes take 20-30 seconds under very heavy I/O load, such as when Spotlight’s indexing the disk and Xcode’s compiling something. With the SSD, those delays just went away: I can’t even remember a time where I saw the evil Beachball due to system I/O load.

The most notable difference was in boot time. A lot of people love how Mac OS X is pretty fast to boot (and I agree with them), but when you go to log in, it’s a very different story. If, like me, you’ve got about ten applications and helper programs that launch when you log in, it can take literally minutes before Mac OS X becomes responsive. I clocked my MacBook Pro at taking just over a minute to log in with my current setup on a hard disk (which launches a mere half a dozen programs); the SSD took literally about 5 seconds. 5… 4… 3… 2… 1done. What is thy bidding, my master? I wish I’d made a video to demonstrate the difference, because it’s insanely faster when you see it. 10x faster login speed is nothing to sneeze at.

However, aside from boot up time, normal day-to-day operation really was about the same. Sure, it was nice that applications launched faster and it booted so fast that you don’t need to make a coffee anymore when logging in, but those were the only major performance differences that I saw. Mac OS X and other modern operating systems cache data so aggressively that I guess most of the data you’ll read and write will usually hit the cache first anyway. The lower sustained write performance didn’t end up being a problem at all: the only time I noticed it was when I was copying large torrented downloadsfiles around on the same drive, but that wasn’t slow enough for me to get annoyed. The one benchmark that I really cared about—compiling—turned out to take exactly as long on the SSD as the hard disk. I thought that maybe it was possible that random I/O write speed was a possible bottleneck with gcc; it turns out that’s not true at all. (I’ll also point out that I was using Xcode to drive most of the compilation benchmarks, which is one of the fastest build systems I’ve seen that uses gcc; no spastic libtool/automake/autoconf/autogoat insanity here.) Sorry to disappoint the other coders out there.

Aside from performance, the total silence of the SSD was a nice bonus, but it’s not something that you can’t live without once you’ve experienced it. In most environments, there’s enough background noise that you usually don’t hear the quiet hard disk hum anyway, so the lack of noise from the SSD doesn’t really matter. It was, however, very cool knowing that you could shake your laptop while it was on without fear of causing damage to your data. I’m usually pretty careful about moving my laptop around while it’s on, but with an SSD in there, I was quite happy to pick up the machine with one hand and wave it around in the air (as much as you can with a 17” MacBook Pro, anyway).

So, with all the nice small advantages of the SSD, you may be wondering why it’s no longer in my MacBook Pro. Here’s some reviews of the disk on newegg.com that may give you a hint:



It turns out those reviewers were right. Two months after I bought it, the Masterdrive MX completely died, which seemed like a pretty super talent for an SSD. The Mac didn’t even recognise the disk; couldn’t partition it; couldn’t format it. So much for SSDs not crashing, eh?

While SSDs don’t crash in the traditional manner that a hard disk may, there’s a whole number of other reasons why it might crash. RAM’s known to go wonky; there’s no reason why that can’t happen to solid-state memory too. Maybe the SATA controller on the disk died. No matter what the cause, you have the same problem as a traditional hard disk crash: unless you have backups, you’re f*cked. Plus, since I was on holiday down at Mount Hotham, my last backup was two weeks ago, just before I left for holiday. All my Mass Effect saved games went kaboom, and I just finished the damn game. André not very happy, grrr.

So, what’s the PowerPoint summary?

  • The Super Talent Masterdrive MX would be great buy if it didn’t friggin’ crash and burn your data with scary reliability. Even if you’re a super storage geek, avoid this drive until they have the reliability problems sorted out.
  • The Powerbook Guy on Market St in San Francisco is awesome. They were the guys to install the SSD in my MacBook Pro, and were extremely fast (two-hour turnaround time), professional, and had reasonable prices. (I would’ve done it myself, but I’d rather keep the warranty on my A$5000 computer, thanks.) Plus, they sold me the coolest German screwdriver ever for $6. (“This one screwdriver handles every single screw in a MacBook Pro”. Sold!)
  • The MacCentric service centre in Chatswood in Sydney is equally awesome. When the SSD died, they quoted me the most reasonable price I had ever seen for a hard disk swap in a MacBook Pro (have you seen how many screws that thing has?), and also had a two-hour turnaround time. Yeah, I know, decent Mac service in Australia! Woooooah.
  • Back up.
  • SSDs are great. I think they’ll complement rather than replace hard disks in the near future, and possibly replace them entirely if the price tumbles down enough. Next-generation SSDs are going to completely change the storage and filesystem games as they do away with the traditional stupid block-based I/O crap, and become directly addressable like RAM is today. Just don’t believe the hype about SSDs not crashing.

I, for one, welcome the solid state society. Bring on the future!

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Mac Developer Roundtable #11

The Mac Developer Network features an excellent series of podcasts aimed at both veteran Mac developers and those new to the platform who are interested in developing for the Mac. If you’re a current Mac coder and haven’t seen them yet, be sure to check them out. I’ve been listening to the podcasts for a long time, and they’re always both informative and entertaining. (Infotainment, baby.)

Well, in yet another case of “Wow, do I really sound like that?”, I became a guest on The Mac Developer Roundtable episode #11, along with Marcus Zarra, Jonathan Dann, Bill Dudney, and our always-eloquent and delightfully British host, Scotty. The primary topic was Xcode 3.1, but we also chatted about the iPhone NDA (c’mon Apple, lift it already!) and… Fortran. I think I even managed to sneak in the words “Haskell” and “Visual Studio” in there, which no doubt left the other show guests questioning my sanity. I do look forward to Fortran support in Xcode 4.0.

It was actually a small miracle that I managed to be on the show at all. Not only was the podcast recording scheduled at the ungodly time of 4am on a Saturday morning in Australian east-coast time, but I was also in transit from Sydney to the amazing alpine village of Dinner Plain the day before the recording took place. While Dinner Plain is a truly extraordinary village that boasts magnificent ski lodges and some of the best restaurants I’ve ever had the pleasure of eating at, it’s also rather… rural. The resident population is somewhere around 100, the supermarket doesn’t even sell a wine bottle opener that doesn’t suck, and Vodafone has zero phone reception there. So, it was to my great surprise that I could get ADSL hooked up to the lodge there, which was done an entire two days before the recording. Of course, since no ADSL installation ever goes smoothly, I was on the phone to iPrimus tech support1 at 10pm on Friday night, 6 hours before the recording was due to start. All that effort for the privilege of being able to drag my sleepy ass out of bed a few hours later, for the joy of talking to other Mac geeks about our beloved profession. But, I gotta say, being able to hold an international conference call over the Intertubes from a tiny little village at 4am in the morning, when snow is falling all around you… I do love technology.

Of course, since I haven’t actually listened to the episode yet, maybe it’s all a load of bollocks and I sound like a retarded hobbit on speed. Hopefully not, though. Enjoy!

1 Hey, I like Internode and Westnet as much as every other Australian tech geeks, but they didn’t service that area, unfortunately.

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