Hi,
I just purchesed a intel 665p 1Tb m.2 NVMe disk and a USB 3.1 gen 2 compatible enclosure that I use with my MacBook Pro M1.
The enclosure is a Icy Box IB-1817M-C31 and is said to be using chipset JMS583.
I did a Blackmagic disk speed test v.3.3 and the results says that i get max approx. 580MB/s read/write using APFS non-encrypted but I'd expect to get closer to 900MB/s.
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If i format the disk to APFS encrypted, it drops down to approx. 100MB/s write and 80MB/s read, but I'd expect to not perhaps get the same throughput as non-encrypted filesystem, but I'd expect somewhere around 500+ MB/s.

Since the Intel 665p disk should handle at least 1500MB/s and the enclosure up to 1000MB/s I would expect to see at least 800+ MB/s.
Looking in system report i see that it says its connected with 10Gbit/s which is what to expect, but the performance i get is roughly halt of that.

Anyone else experiencing this with slow transfer speed on the M1 with USB 3.1 Gen 2 compatible disks(eq 500MB instead of close to 1000MB/s)?
Also anyone else seeing a huge performance drops with APFS Encrypted volumes?
I just purchesed a intel 665p 1Tb m.2 NVMe disk and a USB 3.1 gen 2 compatible enclosure that I use with my MacBook Pro M1.
The enclosure is a Icy Box IB-1817M-C31 and is said to be using chipset JMS583.
I did a Blackmagic disk speed test v.3.3 and the results says that i get max approx. 580MB/s read/write using APFS non-encrypted but I'd expect to get closer to 900MB/s.

If i format the disk to APFS encrypted, it drops down to approx. 100MB/s write and 80MB/s read, but I'd expect to not perhaps get the same throughput as non-encrypted filesystem, but I'd expect somewhere around 500+ MB/s.

Since the Intel 665p disk should handle at least 1500MB/s and the enclosure up to 1000MB/s I would expect to see at least 800+ MB/s.
Looking in system report i see that it says its connected with 10Gbit/s which is what to expect, but the performance i get is roughly halt of that.

Anyone else experiencing this with slow transfer speed on the M1 with USB 3.1 Gen 2 compatible disks(eq 500MB instead of close to 1000MB/s)?
Also anyone else seeing a huge performance drops with APFS Encrypted volumes?
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