Comparison: Internal vs. External NVMe

[DRDR]

I ran some tests with the base Mac Studio with M1 Max, APFS Encrypted disks

Internal SSD (512 GB):

External SSD RAID 0 Set (Thunderbolt 3, Sabrent Dual NVMe Enclosure EC-T3DN with Samsung 970 Evo 2 TB and Samsung 970 Evo Plus 2 TB)):

 

[TTYS0]

That write speed on the internal is _crazy_!

 

[DRDR]

That write speed on the internal is _crazy_!

Yes and the external solution is not bad as well. So I do not regret getting the small internal drive, as long as it is doing its housekeeping as fast as possible.

 

[F-Train]

I ran some tests with the base Mac Studio with M1 Max, APFS Encrypted disks

External SSD RAID 0 Set (Thunderbolt 3, Sabrent Dual NVMe Enclosure EC-T3DN with Samsung 970 Evo 2 TB and Samsung 970 Evo Plus 2 TB)):

I haven't looked at your chart, but Samsung's 970 EVO Plus is severely limited on write speed. For discussion about this, see the thread below and Sonnet Tech's .PDF comparing SSD performance, specifically footnote #9.

 

[F-Train]

This Mac Studio thread offers discussion and comparison of several external options: Thunderbolt 4 & NVMe M.2 External Storage: Read/Write Speeds?

 

[atonaldenim]

Curious results, I'm not sure how an external SSD on a single Thunderbolt port could get more than 3000 MB/s read or write, isn't that the theoretical limit? Perhaps some kind of caching happening?

 

[F-Train]

Curious results, I'm not sure how an external SSD on a single Thunderbolt port could get more than 3000 MB/s read or write, isn't that the theoretical limit? Perhaps some kind of caching happening?

Yes, for an effective RAID 0 with these NVMe M.2 SSDs you need two enclosures, or a dual enclosure with two outputs, and two Mac Studio Thunderbolt 4/3 ports. That is also discussed in detail in the link in post #5 above.

The real life limit for a single Mac Studio Thunderbolt 4/3 port appears to be 2.7 - 2.8GB/s. Setting up drives in RAID 0 doesn't change that.

 

[OSB]

The Sabrent/Samsung write speeds look about right, but those read speeds are unicorn dust. Even if every last bit of TB4 bandwidth could be devoted to the drive (it can't) transfer speeds would top out at 5GB/s. Your read speeds are reporting somewhere in the area of 9GB/s.

As F-Train points out, the real-world limit of TB4 data transfers is about 2700MB/s. Some kind of read caching seems to be happening here.

 

[DRDR]

Yes, it looks strange, there must be some caching going on.

When copying a 36 GByte file with finder Internal SSD <-> External Sabrent Raid 0 SSD I get 2.5 GByte/s external read and 2.1 GByte/s external write performance. With a Samsung 980 Pro in a Sonnet Echo Express Enclosure I get 2.4 GByte/s read and write performance.