Among the different configuration options available when using the OWC Data Doubler in your MacBook or MacBook Pro is setting both drives to function as a RAID 0 (striped) array. This combines both drives (the one in the Data Doubler equipped optical bay and the one in the original hard drive bay) into a single volume, which provides an increase in data access speed.
Since we’ve had several questions about this, we decided to put this configuration to the test by using different combinations of hard drives and SSDs to determine which offered the best balance of price, capacity and performance.
Our test machine was a 2011 13″ MacBook Pro (MacBookPro8,1) with a 2.3GHz Intel Core 5 processor and 4GB of RAM. Inside, we replaced the optical drive with an OWC Data Doubler to allow us to utilize a second drive.
For simplicity’s sake, we tested four configurations:
- Two Mercury EXTREME Pro RE 50GB SSDs configured as a RAID 0*
- Two 2.5″ Seagate Momentus 7200.4 500GB 7200RPM hard drives configured as RAID 0*
- One Mercury EXTREME Pro RE SSD in the Hard Drive Bay and one of the Seagate hard drives in the Data Doubler. For this test, we installed the OS on the SSD and relocated the Home folder to the larger hard drive.
- One Mercury EXTREME Pro RE SSD in the Hard Drive Bay and one of the Seagate hard drives in the Data Doubler. All the software was on the SSD, leaving the 500GB as “general” storage.
*Note that due to the nature of RAID 0, we would highly recommend if you are working with important files that you consider getting an external drive for backup purposes. If you do have a drive failure in a RAID 0 setup, all your important information could easily be lost. Even if you are not going with a RAID 0 setup, it is important to keep a backup of any information you do not want to lose.
We ran two different performance tests. The first was the same boot test we use in our SSD shootout videos. It times how long it takes to boot Mac OS X and launch 4 apps from Adobe Creative Suite.
The second test was the same Photoshop action used in our Memory Benchmark Tests. Since this test generally fills the available amount of memory, and then goes to the scratch disk, this test offers some good insight as to disk performance as Photoshop reads and writes from the default drive.
We’re sure you are as excited to see the results as we were. So, without any further ado, here we go:
Boot Launch Test
- Configuration 1: 56.67 seconds
- Configuration 2: 91.97 seconds
- Configuration 3: 57.12 seconds
- Configuration 4: 59.68 seconds
Photoshop Action Test
- Configuration 1: 132.12 seconds
- Configuration 2: 171.12 seconds
- Configuration 3: 143.40 seconds
- Configuration 4: 136.21 seconds
As expected, the clear speed champ of the testing was Configuration 1, with the dual Mercury EXTREME Pro RE drives setup in a striped array (RAID 0). If you are looking to get the most performance possible, this is clearly going to be the way to go, but it does have the highest cost factor involved at this time, so it may not yet be a viable option for the everyday user if you have a lot of data to move around.
Configuration 2 (two 7200RPM Drives in a RAID 0) gave the slowest results – up to 62% slower – as it uses two standard SATA drives, though is was the lowest cost option out of the configurations tested. I was personally surprised it did as well as it did but, in hindsight, that does reflects the benefits of RAID 0 helping to boost the drive’s performance. Though it came in last for overall performance, if you are looking for the most cost affordable solution with the largest amount of storage space, this can be an attractive setup.
The remaining two configurations offer perhaps the best balance in price, capacity and performance. Relocating the home folder in Configuration 3 helps shave a bit off of the boot times, but has an adverse affect with a little longer delay in the Photoshop test compared to the standard setup of Configuration 4. You can’t go wrong with either setup as you get both speed gains and storage capacity, but depending on what your situation is, you may find one or the other to be slightly better for you.
Even with the smallest SSD drives, which are certainly affordable for nearly every user with current prices starting at $99, you can give yourself a sizable performance boost by arranging them in a RAID 0. However, if you need the extra storage space, consider a single SSD, a large capacity hard drive, and a Data Doubler so you can still benefit from SSD performance while having enough room for your files.
Editor’s note: This article was initially written prior to the release of the Mercury EXTREME Pro 6G. Subsequent testing found that when placed in the 6Gb/s main drive bay of the 2011 MacBook Pros, in Configuration 3 or 4, the results were considerably better performance. However, this is only in the case of a SINGLE 6Gb/s drive – when two SSDs are put in a RAID 0, as in Configuration 1, the 3Gb/s speed of the optical bay will slow the RAID down to speeds similar to those shown above. We will revisit this topic once the Mercury Extreme 6G RE SSDs (currently under development) are released later this year.
For any model MacBook Pro prior to the 2011’s, though, the above scores should give an idea of the kind of performance to expect.