Compare Speed Differences Between 2-, 3-, and 4-Drive SSD RAIDS

Recently, I bought an 8 TB OWC Thunderblade for myself to speed my editing. This 4-blade, NVMe SSD RAID is really fast – though not as fast as it could be.

NOTE: Read my review of the Thunderblade here.

However, because this unit contains four separate SSD drives (called “blades”) this also gave me the ability to test the speed differences between different RAID configurations.

NOTE: All my test results and charts are available in a PDF at the end of this article.

In this article, I’ll show you real-world speed results and compare them to what we need for single and multi-camera editing.

MY SYSTEM

Using a 16″ MacBook Pro (with an M1 Pro chip) running macOS Monterey, I formatted a 1 TB Samsung T-5 PCIe SSD using APFS in macOS Monterey. It was connected via USB-C.

I then compared it to various configurations of an OWC Thunderblade NVMe SSD RAID.

NOTE: Recent testing shows that macOS Ventura is 15-25% slower reading and writing SSD drives. Expect your results to be lower than mine. (Here’s the article: Warning: SSD and ExFAT Speeds are Much Slower in macOS Ventura & Reformatting is Trickier. My hope is that Apple fixes this in future updates.)

THE TESTS

Using Disk Utility, I combined the internal drives of the Thunderblade into three different RAID 0 configurations: 2-drive, 3-drive and 4-drive.

• All RAIDs were formatted into APFS, which is the recommended format for SSD drives.
• All RAIDs were created using Disk Utility because past tests show that this software creates the fastest RAIDs.
• All tests were measured using AJA System Test (Full version) because the engineers at OWC told me that they trust the results of this software.
• Each test was run five times, then the results were averaged.

THE RESULTS

If we set the speed of a PCIe SSD equal to 100%:

• A single blade of the Thunderblade formatted as an NVMe SSD is slightly less than twice as fast. (A stand-alone NVMe SSD should be MUCH faster than this.)
• A 2-drive RAID 0 is roughly 3 times faster.
• A 3-drive RAID 0 is 5 times faster.
• A 4-drive RAID 0 is slightly less than 6 times faster.

Converting these same numbers into MB/second (MB/s):

• A PCIe SSD is roughly 400 MB/s.
• A single blade formatted as an NVMe SSD is about 700 MB/second, writes are slower than reads. (A stand-alone NVMe SSD should be MUCH faster than this.)
• A 2-drive RAID 0 is roughly 1,200 MB/s, writes are slower than reads.
• A 3-drive RAID 0 is roughly 1,800 MB/s, writes are slower than reads.
• A 4-drive RAID 0 is roughly 2,200 MB/s, reads are slower than writes.
• The maximum speed of Thunderbolt 3/4 is 2,800 MB/s. A 3- or 4-drive SSD RAID should totally fill that pipe; but, currently, they don’t.

Read speeds are more important than write speeds for media editing. No current video editing software will render or export media at anywhere close to these write speeds.

NOTE: A stand-alone NVMe SSD should be closer to 2,500 MB/second. However, I don’t have a stand-alone unit to test. A single blade on the Thunderblade should max out around 975 MB/second.

IS IT FAST ENOUGH?

While it is helpful to see these speed numbers, the bigger question remains: Are these speeds fast enough? This chart (above) from Blackmagic Disk Speed Test displays the results of editing media on a 2-drive SSD RAID. As you can see, all current video formats are easily supported.

NOTE: Well, OK. 12K 60fps is not. How often are you editing 12K 60 fps today?

Where 3- and 4-drive RAIDs make a big difference is in multicam editing. Based on some unofficial tests that I did, a 3-drive SSD RAID connected via Thunderbolt 3/4 easily supports 10 streams of 4K video, and about 20 streams of proxy video. I would expect the 4-drive RAID configuration to support 15 streams of 4K and 30 streams of proxy video.

NOTE: As with everything in technology, always test your system before you start editing to make sure it is fast enough to support what you want to do.

While the speeds of 3- and 4-drive configurations are slower than I would expect, they are still fast enough to support significant multicam editing, especially using proxies.

SUMMARY

I found this exercise very helpful in seeing the differences in speed between different  RAID configurations. We think of SSDs as being “infinitely fast.” But, like all tech, they have limits. You can use these charts to help you plan the gear you need as your media needs expand.

EXTRA CREDIT

• Here’s a PDF (137 KB) detailing my test results and charts. (Due to limitations in Numbers, I can’t properly label the charts.)

---

Bookmark the permalink.