Ever woken up one morning and just wondered why you spend a good portion of your day waiting for your laptop to boot up?
Me too.
I was curious to see if there was a speed improvement booting OS X “El Capitan” from an SD card versus the internal hard drive.
The SD card was 32Gb:
And I’d also purchased a card reader, even though my MacBook Pro has a built in card reader:
The results were a bit interesting:
| Mac Model | Storage Medium | Connection Type | Boot Speed (Seconds) |
|---|---|---|---|
| 2009 13-inch MacBook Pro | Seagate Momentus XT | Internal Bus | 1:43 |
| Lexar 32Gb SD | Card Reader | 1:21 | |
| Staples USB Card Reader | 1:23 | ||
| 2011 Mac Mini | Internal Hard Drive | Internal Bus | 1:06 |
| Lexar 32Gb SD | Internal Card Reader | 0:44 |
So, bearing in mind that this is a highly unscientific experiment, there’s a roughly 20 second boost to running the OS on an SD card over the internal drive.
We have to take into account that the internal drive in the MacBook Pro is a hybrid, meaning the most frequently read sectors on the conventional disk should be cached in the SSD section. There’s a good chance many of these sectors belong to core OS files, and so we might expect a significantly slower boot time from a conventional hard drive.
Also of interest is there’s little performance improvement using the internal card reader over a USB one, implying all these are travelling down the same bus.
If I’d realised that if there were significant performance gains to be had, it could have been worth going to the trouble of building a core storage drive for El Capitan’s system files, but from this test the performance gain might not outweigh the effort.
There’s something to talk about at your next dinner party.
