I have done long tests with Samsung drives this evening, hoping I could figure it out..
I tested again the 960 Evo and PM981 (which is newer than the 960)
Tests were made with both macOS 10.13.4 (beta 0) and Linux Xubuntu 17.10 on a 13" rMBP late 2013, and with both black v.3 and large green v.2 sintech adapters.
Results with Linux and the 960 Evo/Pro :
- never had any hang or panic... Sleep works and resume properly. Reboot works and never present a blinking folder even on 2013-2014 mac, with both green and black adapters !
Copy of 400GB of datas can be made without trouble up to a fast external Samsung T3 , at a medium speed higher than 300 MB/sec
Results with macOS and the 960 Evo/Pro
- reboot fails with the black sintech adapter with a blinking icon
- reboot works 100% times without issue with the large green adapter
- huge data copy-I/O transfers work without issue from a NVMe APFS boot drive running 10.3.3
- huge data copy-i/o transfers randomly causes kernel panics while booted from a NVMe APFS drive under 10.3.2. Same thing while booted from an HFS+ drive (any version of High Sierra)
Results with Linux and the PM981 :
- no problem at all. Disk is fast, reboot works 100% of the time, sleep seems to work perfectly; no single issue
Results with macOS and the PM981 :
- disk impossible to use. Read works fast (1500MB/s) but write almost always fails ! (with both models of adapters).
Write on a APFS or HFS disk can write up to 100MB a 5 MB/sec only... after a while, I got spinning ball cursor and no transfer at all, then all this followed by a KP...
Conclusions so far :
- as for kernel panics issues : it sems macOS doesn't handle well the combinaison of Samsung NVMe drives formates in HFS+... (or Samsung NVMe drives formatted in APFS under 10.13.2 or lower)
- also macOS doesn't like the combinaison of both Samsung NVMe and Sintech black adapter... it results of a blinking icon folder
I have noticed no problem at all with any combinaison of linux / apple hardware / samsung NVMe drive / sintech adapter
Also all 2015-2017 macs are free from reboot problems so they can use a black sintech adapter with no issue !
And last, I feel quite optimistic, at least the fact that it works perfectly with linux/ windows makes me hope that the remaining issue (very noticeable with the PM981) is only with the macOS kext and the way macOS handles samsung NVMe drives..