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Drobo 5D — As a Photoshop Scratch Disk
B&H Photo supplied the Data Robotics Drobo 5D for testing, along with five Hitachi 4TB hard drives.
Testing was on the fast 2.7 GHz MacBook Pro with Retina display via Thunderbolt.
The diglloydMedium benchmark requires that Photoshop have available about 15.7 GB of real memory for itself, which means that a machine with less than 24GB of system memory will suffer in performance on this test due to the need for Photoshop to write and read from the scratch disk. Hence the speed of the scratch 'disk' has an important influence.
Results
The single internal 512GB SSD in the MacBook Pro Retina offers far superior performance as a scratch disk compared to the Thunderbolt Drobo 5D with its five hard drives. The advantage for the SSD would grow with larger jobs.
The Drobo 5D is appropriate for high capacity storage at moderate speeds, but it is absolutely not a preferred solution for key areas of workflow.
The Drobo 5D does accept an mSATA accelerator card, but the Drobo PR firm declined to make one available so it was not tested. In any case, a dedicated SSD for high performance needs (e.g., Photoshop scratch) is the smart move.

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