My Google-issue Mac is pretty nice, but I decided to improve it by swapping obsolete optical storage for not-obsolete-yet spinning rust. With benchmarks for the disk geeks in the crowd.
It’s a late-2011 15" MacBook Pro model; 8G and the big matte screen. It came with SSD storage, said to be fast but at 128G kinda cramped. That’s enough room for all the apps and source code and presentations and libraries and IDEs that any sane person could want. You could have all that stuff and squeeze in my blog publishing system and maybe even an AOSP or two. But if I wanted to keep photo-archives or video projects or large amounts of uncompressed audio around, well, nope.
To be fair, there’s no reason Google owes me storage for this stuff, the majority of which is personal. So one solution would be to carry a personal computer around but that would be messy, and it’d mean I couldn’t do Google stuff in between editing photos.
Another solution would be to get an outboard disk, and I did that. But it was awkward on airplanes and in my favorite comfy chair, and wasn’t the fastest thing in the world.
So I bought a 1-Terabyte 5400RPM Data Doubler from OWC, and swapped it in for the optical drive that I never use. My electronics-hands-on technique is very limited, but they had a really well-put-together how-to video, and that made the task straightforward, if not exactly easy or fast.
How Big? · The amount of space is, well, ridiculous. I’ve got the contents of a thousand ripped CDs (losslessly encoded of course), several years worth of image files (because I discard everything that’s not sentimental or publishable), some video projects, and of course that Android OSS dump; the big disk isn’t even half full.
How Fast? · Theory says that SSDs are massively faster than spinning rust, and bloggers have waxed effusive about the performance boost. Since I’m a quantitative type, and also author of Bonnie, an elderly but quite widely used filesystem benchmark, I thought I’d find out just how fast.
I ran Bonnie on both disks with a 20G test file, which ought to be enough to bust the cache on an 8G machine; here’s what she told me.
|Sequential Output||Sequential Input||Random Seeks|
|Per Char||Block||Rewrite||Per Char||Block|
So Bonnie thinks that the SSD can pump data out about 40% faster, suck it in about 30% faster, and do random seeks about 25 times faster. The system says:
Both are running through Serial-ATA Intel 6 Series chipsets with a 6G/sec link speed.
The SSD is advertised as an “APPLE SSD TS128C”. (AnandTech says it’s a Toshiba).
The spinning rust is advertised as a “SAMSUNG HN-M101MBB”.
This is running a recent OS X 10.7 release, and FileVault is in effect on the SSD but not the spinning rust. Which of course makes the comparison unfair, only not really, because everybody’s primary disk should bloody well be encrypted these days. And my intuition is that the CPU has enough horsepower to do the encryption without having any trouble staying ahead of the SSD. This would explain why the %CPU columns are generally higher in the SSD row of the Bonnie output.
In general, I have to say I’m pretty happy with the performance of the add-on disk.
Obligatory Geek-Greybeard Shock & Awe · I mean, holy crap. 2.2GHz quad-core I7, 8G of RAM, 1680x1050, two video cards one of which is a Radeon 6750M, and 1.1T of storage. This is a meat grinder.