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Ellis V writes:
My media is stored on an external Thunderbolt RAID array.
As I creep into doing video work I keep running into the out of storage /temporary memory message in FCP X. Currently this machine has the stock 512Gb SSD installed and I am looking at replacing it with either the OWC Mercury Extreme 6G 2TB or the Mercury Electra 6G.
With FCP X (and Lightroom Classic CC + Photoshop CC 2018) will I see a real world performance difference between these two drives?
I'd love to get one of the new iMac Pro ( most likely a 10 core model with 64GB RAM but that won’t happen until t least late 2019.
MPG: SATA drives like the OWC Mercury Extreme Pro 6G or OWC Mercury Electra 6G peg at ~520 MiB/sec at best, due to the SATA interface. Still that is plenty fast mor most video use. However, a key question is where/how that drive is connected.
In my testing, USB external enclosures for SATA drives (and/or the computer USB interface) tend to cut the actual speed down by up to 25%, e.g., 420 MB/sec vs 520MB/sec is typical. I have yet to find any USB enclosure that delivers full speed.
For full performance of SATA drives on a Mac, use the OWC Thunderbolt Drive Dock. It can accomodate dual SATA drives. While it is not nearly as convenient as something like the OWC Mercury Elite Pro Mini, the form factor matters little on a desktop computer.
An OWC Thunderbay 4-drive RAID (available in Thunderbolt 2 or Thunderbolt 3) is actually faster for sustained transfer speeds when configured with modern hard drives; you should seen close to ~800 MiB/sec with a RAID-5 array. So that might actually be better for footage, albeit more expensive for that much storage.
The issue is that when/if random access is needed, hard drives have higher latencey; in such cases an SSD is usually much faster.
Most video work is not about writing data; footage is laid down and pointers to it are moved around. Thus read speeds matter most hence the Extreme or Electra models are likely to perform pretty much the same.
For really top-end video, look at Thunderbolt 3 and drives engineered for very fast and very consistent performance like the OWC Envoy Pro EX Thunderbolt 3, VE (“Video Edition”)—my test results there show the consistency in performance. Or the OWC Thunderblade 4, which is expressly designed for super high end video users.
Shown below are various products related to the foregoing discussion.