Poor performance with NVMe and High Sierra

[inequals]

Thanks so much!

 

[greenhobby]

RehabMan,

As my info says, I've got a GA-Z170x-ud5 th motherboard. I upgraded to high sierra on one of my SSD's. It did convert the SSD to AFPS. I then installed a Samsung 960 Pro NVMe card formatted it to APFS and restored my Carbon Clone backup to it. It does boot and the system runs. I've noticed though that it does sometimes slow down (also takes a while to boot). I was not aware that we should be using HPS+J on NVMe disks. I ran the Black Magic disk test and am seeing 734 MB/s reads and 745 writes. Should it be faster? If I need to convert my boot NVMe disk to HFS+J is there a way to do it besides reformat and restore?

thanks much, GH

 

[RehabMan]

RehabMan,

As my info says, I've got a GA-Z170x-ud5 th motherboard. I upgraded to high sierra on one of my SSD's. It did convert the SSD to AFPS. I then installed a Samsung 960 Pro NVMe card formatted it to APFS and restored my Carbon Clone backup to it. It does boot and the system runs. I've noticed though that it does sometimes slow down (also takes a while to boot). I was not aware that we should be using HPS+J on NVMe disks. I ran the Black Magic disk test and am seeing 734 MB/s reads and 745 writes. Should it be faster? If I need to convert my boot NVMe disk to HFS+J is there a way to do it besides reformat and restore?

thanks much, GH

You should benchmark your NVMe on Windows. Then you know what to expect and whether you have a hardware/installation problem (eg. running out of PCIe lanes).

And definitely HFS+J will lead to less problems due to TRIM always enabled for NVMe... and TRIM+APFS having problems with certain non-Apple SSDs.

 

[greenhobby]

You should benchmark your NVMe on Windows. Then you know what to expect and whether you have a hardware/installation problem (eg. running out of PCIe lanes).

And definitely HFS+J will lead to less problems due to TRIM always enabled for NVMe... and TRIM+APFS having problems with certain non-Apple SSDs.

Thanks. Is there a way to convert from APFS to HFS+J without format and restore?

 

[RehabMan]

Thanks. Is there a way to convert from APFS to HFS+J without format and restore?

Some people have reported using CCC to clone APFS->HSF+J (external), then back to target HFS+J.
(it works because CCC is file-based cloning software)

 

[greenhobby]

Some people have reported using CCC to clone APFS->HSF+J (external), then back to target HFS+J.
(it works because CCC is file-based cloning software)

Sure. Thanks for the response. Do you have a link to where these issues (APFS, trim, etc) are being discussed in detail?

 

[RehabMan]

Sure. Thanks for the response. Do you have a link to where these issues (APFS, trim, etc) are being discussed in detail?

There is some discussion here:
https://www.tonymacx86.com/threads/...n-high-sierra-update-or-fresh-install.232855/

Other places too.
The problems with TRIM+APFS are relatively common.

 

[telepati]

- ioreg shows NVMe with APFS.

Why is our APFS disk shown 'untitled' in ioreg?

 

[RehabMan]

Why is our APFS disk shown 'untitled' in ioreg?

'Untitled' will show for partitions formatted with a file system that macOS doesn't support, or for partitions that don't have a volume label (eg. Windows partitions with no label).

 

[telepati]

Did you install on APFS or HFS+J?
If you installed APFS, try HFS+J instead.

My Samsung 960 NVME is slow too. My system is HFS+J.

I tried TRIM on/off and I also tried VBoxHfs.efi this is worse than HFSPlus.efi.

Results;

HFSPlus.efi
800MB/s Write / 2500MB/s

VBoxHFS.efi
650MB/s Write / 2000MB/s

I attached all problem reporting files. Could you please tell me what is missing or this is the common problem? Thank you.