USB 3.0 SSD RAID - Cheaper and fast external storage solution
Saturday, May 10, 2014
Background
Recently I got a Macbook Pro as my daily use machine. As MacBook Pros are too expensive, I decided to go for the 13" mid-configuration (A$1750 for a 13" machine with 8G RAM and 256G SSD) as I don’t need a graphic card and a powerful CPU. I got the machine in JB Hi-Fi (yes, that is the name of an Australian company) so there is no way for me to upgrade the solid state drive. Also the 2014 Macbook Pro is so locked down, meaning there is no reason for you to open it up because there is no way to upgrade anything, I have no choice but to use external storage.
Use Case
The reason I want to have an external storage is for virtual machines. I use a lot of virtual machines (Linux, Windows) to do my development work (programming and testing) and also use them to finish my uni assignments. For the MacBook itself, after I installed software that I need (Adobe Creative Cloud, PhpStorm, IntelliJ and many more), I have about 150G left. I need about 120G for few Windows machines and 50~80G for few Linux machines.
When you run operating systems on an external drive, it needs to have a fast read speed and reasonable write speed. It’s just my case as I don’t do media work so I don’t have to worry that the drive is not good enough for editing 1080p video, or for some professionals out there, editing 4K video. I just need the speed to be reasonably fast so I don’t lose my patient when debugging the IE 8 compatibility issue on a Windows XP machine, nor when testing emails in Outlook 2013.
My Solution
Initially, I just got a normal USB 3.0 spinning hard drive, which I gave up using it after about 30 minutes. It’s just too slow to run virtual machines on it.
Then I started to look for better solutions. I came across few options:
- Pre-build Thunderbolt 2 SSD Raid, by Lacie: Yes you are right, this damn thing cost A$1600 at the time of writing this article. The specification claims it to have 1,375MB/1,180MB read/write speed per second. I love it, but it is way beyond my budget!
- WD My Passport Pro 2TB: This was in my consideration initially, as it is not too expensive yet performs at 230MB read/write per second. As then I found that I have two spare SSDs (two 128G SSD from OCZ Vector) and a 1TB drive I bought earlier. I found few reviews about this drive but as it seems to be pretty new there is not much information about it.
- No brand, I decided to go for two 250G SSD with USB 3.0 enclosures. The total cost for me is about A$30 (I only need to buy two hard drive enclosures, so for you it may be around A$250.
The Setup & Benchmark
I used the default Disk Utility to configure the RAID. You can just create a RAID 0 array and then add your volumes to that RAID configuration. Then you will be able to format them and start to use it. I won’t provide too many details here as I think you will be able to find great tutorials on how to set them up. Here is the benchmarks: (around 470MB/s)
Conclusion
This setup did save me some money, and here is a brief summary of the pros and cons:
Pros:
- Cheap and easy to set up.
- Configuration really flexible, you can get different SSDs or use existing ones.
- Speed is faster than HDD, and I am really happy with the performance.
Cons:
- Two USB cables will use up all the ports of your MacBook Pro.
- Having two USB cables are really annoying, but that’s what you pay for the low price.
Update (May 14, 2014)
I got a USB 3.0 hub for these two drives, as I think the theoretical speed of USB 3.0 is 5Gbit/s or 625MB/s, so one USB hub may be able to handle the speed above. However, the reality is about 270MB/s. I haven’t tried any other USB hub so I am not sure whether it’s the problem of the USB hub or the limitation of the port speed.