TRIM should only affect write speed, but not read speed.
Something is very wrong with that read speed on a NVMe SSD.
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PCIE M.2 NVMe on MacPro
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TRIM should only affect write speed, but not read speed.
Something is very wrong with that read speed on a NVMe SSD.
Sorry my mistake it's the write speed that's slow. I wonder if it's the WD device. most people seem to use Samsung SSDs. but it is SO slow that it does seem like a trim issue
[doublepost=1528888681][/doublepost]Also as an experiment i tried it in slot 2 (x16) and the write speed remained at 200 but the read speeds went down to 700. Not what I expected at all.
I think it's TRIM issue.
You may need to turn ON TRIM, boot into recovery partition, then Run first aid in disk utility to manually TRIM the SSD.
Just turn TRIM ON won't help if the SSD is already "dirty" and "full". You need to manually TRIM it in order to let it free up the cell for next high speed write in operation.
you know as they say
sometimes you just gotta fsck it
if the SSD is formatted as HFS+ and you have trim enabled
then running fsck in Single user mode before you mount the drive, will manually trim the SSD
Thanks for that but I'm afraid it made no difference. I also ran trimforce enable in the terminal once more to be sure. First aid ran but didn't give a report or anything but since the disk was yet to be written to (except for Black Magic's temp file of course) it probably wouldn't have done much. Maybe the Lycom card doesn't support this particular drive. I'm pretty sure I checked that before I bought but I'll check again.
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Ah! now we might be getting to it. I was advised to format APFS. Is this not the way to go?you know as they say
sometimes you just gotta fsck it
if the SSD is formatted as HFS+ and you have trim enabled
then running fsck in Single user mode before you mount the drive, will manually trim the SSD
are you booting from this NVMe drive or?
when in single user mode
fsck -fy
will check/fix up the Boot/Root Device it is possible to run fsck on other drives however i have not looked into that. so i cant tell you how currently.
the reason I mentioned HFS is when an SSD is APFS formatted running fsck no longer manually trims the blocks sadly. (or it does not appear to do so)
when in single user mode
fsck -fy
will check/fix up the Boot/Root Device it is possible to run fsck on other drives however i have not looked into that. so i cant tell you how currently.
the reason I mentioned HFS is when an SSD is APFS formatted running fsck no longer manually trims the blocks sadly. (or it does not appear to do so)
Tried to reformat to HFS+ but it no longer seems to be an optionyou know as they say
sometimes you just gotta fsck it
if the SSD is formatted as HFS+ and you have trim enabled
then running fsck in Single user mode before you mount the drive, will manually trim the SSD
Doesn't seem to be possible once formatted to APFS unless I'm missing something
Make sure you select the drive, not the partition. You can't format a drive inside a partition.
ran fsck -fy
It just seemed to just check the OS HD as far as I can see. All the same I'm afraid. NVMe doesn't exactly seem plug and play on Mac Pro 5,1s -or maybe I'm just unlucky.
I wasn't planning on attempting to use this to boot from. I'd just just be happy to get it writing at a reasonable speed.
OK after a bit googling it seems that once you've booted in recovery mode HFS+ is no longer an option.
It just seemed to just check the OS HD as far as I can see. All the same I'm afraid. NVMe doesn't exactly seem plug and play on Mac Pro 5,1s -or maybe I'm just unlucky.
I wasn't planning on attempting to use this to boot from. I'd just just be happy to get it writing at a reasonable speed.
OK after a bit googling it seems that once you've booted in recovery mode HFS+ is no longer an option.
You have to boot from another drive. As I said, you cannot format a drive if you already inside a partition (you boot from a partition). And you can't format your boot drive.
But if you boot from another drive's recovery partition. You can format your APFS SSD back to HFS+.
click view then "show all devices"
then you will see the actual SSD it self then you can format it as whatever
(I know Modern disk utility sucks...)
Don't quite understand your point I'm booting from a regular HD
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Ok got you but I'm still not seeing HFS+ just MacOS extended and some FAT stuff
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MacOS Extended is HFS+
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And that's exactly why I made post #184 to ask you to choose the drive but not the partition.
OK it's just that when I first formatted a couple of days ago the option appeared as HFS+, anyway I went for macOS Extended (journaled) and its still showing 200 MB/sec write
[doublepost=1528899535][/doublepost]Thanks for you infinite patience BTW
So, the NVMe SSD is now newly formatted to HFS+. And you confirmed TRIM is activated in system info?
Ok well that's different... mine doesn't appear under the SATA/SATA Express heading, just NVMExpress
[doublepost=1528902893][/doublepost]This was the case after I first put the card in 2 days ago.
[doublepost=1528903062][/doublepost]Software? SSD? Card? Mac Pro? I haven't a clue
Is it worth installing a new copy of the OS on a fresh disk?
[doublepost=1528902893][/doublepost]This was the case after I first put the card in 2 days ago.
[doublepost=1528903062][/doublepost]Software? SSD? Card? Mac Pro? I haven't a clue
Is it worth installing a new copy of the OS on a fresh disk?
I just check your SSD's spec and review. 200MB/s sequential write may be normal indeed. Even the 512GB model can only do 300MB/s in real world test.
Jeez where was that chart when I needed it. Guys I've wasted your time and I'm really sorry about that. I can see why the 960 leads the pack.
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On the Scan site it says 700MB/sec. I'm asking for money back.
May be you can only achieve that 700MB/s under very specific condition. I don't know. But so far, this doesn't looks like a good choice for NVMe SSD.
For me, the sole reason to go PCIe SSD is the sequential speed. And this model fail to deliver.
If I only want low latency, SATA SSD is good enough.
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