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 OutputSequential InputRandom Seeks
Per CharBlockRewritePer CharBlock
GBM/sec%CPUM/sec%CPUM/sec%CPUM/sec%CPUM/sec%CPU /sec%CPU
SSD2096.792.2127.510.736.5 8.161.956.7123.410.32771.210.0
Rust2090.884.290.610.639.0 3.894.172.594.5 6.2105.6 1.2

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.


Comment feed for ongoing:Comments feed

From: Norman Walsh (Jun 05 2012, at 07:41)

I did the same thing a while back:

It's certainly nice to have an SSD and plausible amounts of storage. I couldn't quite swing for the 1T, but next time...


From: Nate Abele (Jun 05 2012, at 08:09)

I'm surprised you made no mention of random seek times, since this is where SSD really cleans up, and since one can reasonably assume that random seeks are what most peoples' disks spend most of their time doing.


From: soph (Jun 05 2012, at 09:04)

Got me a very similar MBP last month, very nice.

Bought it with 4G RAM and intend to upgrade it. It seems it can hold 16G, and I’m tempted. Why didn’t you go that route? Did you get the 8G from Apple?


From: Kevin H (Jun 05 2012, at 09:36)

Dear LazyWeb - Can you tell me what it would cost to get this same system for myself?


From: Tom Lazar (Jun 05 2012, at 09:44)

I had a similar setup but instead I put the SSD into the optical drive bay and the spinning disk into the internal bay. The reason is that the latter is much more insulated against vibrations whereas the former actually tends to amplify the HDs noise.

The result was a noticeably quieter setup. YMMV


From: Martin Englund (Jun 05 2012, at 10:54)

I can confirm that it holds 16 GB memory :)

A great addition when you need to run one or more VMs in it.

I can also recommend ZFS from Ten's Complement LLC - great for your extra disk! I'm fiddling with using a partition of the SSD as a ZFS log...


From: Nathan (Jun 05 2012, at 11:34)

Did you consider remote storage? Things like Dropbox or even a free Flickr account may not be suitable for your volume of data, but you have a server and a domain name. ssh tunneling makes things as reasonably secure as an internet-facing server can be. A cronjob or inotify daemon watching a folder and sftping the contents to a remote location would be the work of an evening.

When--not if--your spinning rust decides to croak, how much are you going to lose? All my computers these days have a minimum amount of local storage--40GB or 64GB SSDs, mostly--and a connection to the mothership, backed by a RAID5 with nightly backups. I've lost too much data over the years to accept anything less than that. But I don't shoot in RAW and I don't generate enough data to expose the flaws in this sort of system. I'm curious if you have done so, or if you just went with the HDD approach because it's easy.


From: JeffDM (Jun 05 2012, at 12:43)

SSD's claim to fame was the random seek. In the past, sequential speed has even been below that of an HDD, but the random seek is what makes SSD worthwhile or interesting for consumers.

Flash memory has generally been slower than DRAM, there is a difference in performance because it's a very different kind of silicon.


From: Ariel Weisberg (Jun 06 2012, at 07:16)

Apples to oranges since it is a different SSD, but I got a very different set of results from a benchmark using my quickly thrown together "database" prototype.

I got 43k random reads, and 130 megabytes/sec of sequential write. I know I can do 230 megabytes/sec or so of sequential write if it is a naive application that is just writing.


From: Bud Gibson (Jun 06 2012, at 12:40)

I'm glad to see you went OWC. Really the place for the do-it-yourselfer who may not be so hardware inclined.


From: Z.T. (Jun 12 2012, at 20:57)

Wikipedia says FileVault version 2 in Os X Lion supports hardware AES available in Intel CPUs:


From: Z.T. (Jun 13 2012, at 18:39)

Here are good benchmarks comparing the SSD in mid-2012 MBP with SSDs from Apple's older offerings and with best available in the market:

spoiler: 400MB/sec sequential read and write.


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