Hi,
my Promise Pegasus 2 R4 drive is very slow on Mac mini 2018 with Apple Thunderbolt 3/2 adaptor and Monetary, backup from Pegasus to TB2 HDD about 25MB/s!!!
Same Pegasus on iMac 2014 with Bid Sur get about 300MB/s.
Whats going wrong?
Best regards
Roland
Hello bruno75,
I just installed my new hard drive case and got the following warning when creating the volume:
"Should I format my SoftRAID volume as APFS or HFS+?
APFS is Apple’s first new file system in over 30 years. It offers a host of features not found in HFS+, including native encryption, copy-on-write, snapshots, and greatly improved volume stability. We recommend using APFS whenever you are creating a volume which only uses SSDs as this allows you to take advantage of these great features.
Unfortunately, one of these features, copy-on-write, can result in a volume that quickly becomes unusably slow. This can happen after just a few weeks of use on any APFS volume which uses HDDs. The slowdown will occur on any file which is written after being duplicated with the copy-on-write feature. Copy-on-write is used anytime: a file is copied or duplicated in the Finder and where both copies are on the same volume, when a snapshot of a volume is created or whenever any of the most popular backup utilities are used to back up a volume. For this reason, we do not recommend using APFS on volumes containing HDDs unless you are using the volume for a Time Machine backup.
Time Machine volumes must be formatted as APFS if you are running macOS 11 or later. This includes SoftRAID volumes which contain HDDs.
For a more detailed description of why the copy-on-write feature of APFS results in slow performance with HDDs, check out this video starting at the 3:20 mark."
This text comes from there: https://www.softraid.com/faq/should-i-format-my-softraid-volume-as-apfs-or-hfs/
Now I'm quite angry, I actually spent €800 for nothing!
best regards
Roland
Hello bruno75,
I just installed my new hard drive case and got the following warning when creating the volume:
"Should I format my SoftRAID volume as APFS or HFS+?
APFS is Apple’s first new file system in over 30 years. It offers a host of features not found in HFS+, including native encryption, copy-on-write, snapshots, and greatly improved volume stability. We recommend using APFS whenever you are creating a volume which only uses SSDs as this allows you to take advantage of these great features.
Unfortunately, one of these features, copy-on-write, can result in a volume that quickly becomes unusably slow. This can happen after just a few weeks of use on any APFS volume which uses HDDs. The slowdown will occur on any file which is written after being duplicated with the copy-on-write feature. Copy-on-write is used anytime: a file is copied or duplicated in the Finder and where both copies are on the same volume, when a snapshot of a volume is created or whenever any of the most popular backup utilities are used to back up a volume. For this reason, we do not recommend using APFS on volumes containing HDDs unless you are using the volume for a Time Machine backup.
Time Machine volumes must be formatted as APFS if you are running macOS 11 or later. This includes SoftRAID volumes which contain HDDs.
For a more detailed description of why the copy-on-write feature of APFS results in slow performance with HDDs, check out this video starting at the 3:20 mark."
This text comes from there: https://www.softraid.com/faq/should-i-format-my-softraid-volume-as-apfs-or-hfs/
Now I'm quite angry, I actually spent €800 for nothing!
best regards
Roland
Hello Roland,
While we're unable to speak to the results for the Blackmagic Disc Speed test, we'd recommend reaching out to the app developers to discuss those results.
As it was unclear, do you use the same adapter from your new Mac mini to connect your external hard drive to your older iMac?
Have you already checked for any compatibility issues with the manufacturer of your external hard drive? Another thing to check with the manufacturer would be if there are any possible firmware updates for your drives.
Take care!
Hi there Roland,
We'd like to lend a hand to help with what's happening with your Mac and that drive.
Let's start with better understanding what's happening:
Cheers!
Hello bruno75,
at first thank you for your quick response.
I noticed that hard drives are getting slower and slower because backups are taking longer and longer.
Backup with CCC 2,15TB 27h20min.
My Konfiguration.
Mac mini 2018 3 GHZ 6Core i5, 8GB Ram macOS12.2
Promise Pegasus 2 R4 2x Toshiba MG06ACA8, 2 Arrays watch with Raid1
Apple Thunderbolt 3>2 Adapter
USB FANTEC HDD-Sneaker
HDD Toshiba DT01ACA300 as external Backup Disk
I don't need a Thunderbolt adapter on the IMac because the iMac 2014 has Thunderbolt two, just like the Pegasus2 hard disk drive.
On Mac mini:
Internal backup from Array1 to Array2 with the Time Machine backup, I had the impression that it was already running around the clock.
So I to a Speed Test with Blackmagic Disk Speed test on the Promise on raid1 Array, write about 170MB/s read about 50MB/s.
After that, I watched the data backup from the CCC, sometimes dizzying to 5 MB/s, the maximum was about 30 MB/s.
Yesterday the Pegasus drive said goodbye during the data backup, crash and cannot bring it online on Mac Mini.
Today I was able to use Disk Utility to repair the disk volume.
A data backup is currently running at a fairly acceptable speed, about 50-80MB/s with CC 6.0.5, just now in 1 hour already 190 GB saved on the external USB hard drive.
On iMac:
After the Pegasus drive on the Mac Mini crashed, I connected it to the iMac to save my data (approx. 1,1TB) after about 8 hours of running time with CCC, the drive crashed again, than 2,5 hours later the backup was finished, 1,1TB in 10,5 hours, Converted that gives 30MB/s.
A Speed Test with Blackmagic Disk Speed test on the same Promise on raid1 Array, write about 290MB/s and read about 150MB/s.
Maybe the Pegasus 2 is EOL? It is now 5 years old, but my other two Pegasus R6 (10 year old) are always working without troubles.
Soory for my bad English, I hope you can unterstand my story.
In summary, I can say that the Pegasus drive crashed on both Macs (Mac Mini and iMac), but the data throughput on the old iMac is faster.
No idea whats going wrong, I think the Mac mini cannot have a malfunction.
The data are so important, because of my work, so I ordered an OWC Thounderbay 8 today and will put it into operation tomorrow and hopping the problem will be solved.
Best regard from Austria.
Roland
Hi Roland,
For your reference, if you'd like to provide product feedback about Apple devices, you can submit yours here: Product Feedback
From the details you provided, along with the video, we aren't able to confirm them as it's provided from a third-party source.
That being the case, we still recommend reaching out to the manufacturer(Pegasus) to look into any workarounds, along with confirming the details listed in the earlier post.
Have a good one!
Hello,
Thanks for replay, I make a Product Feedback.
The Pegasus2 is EOL but have the latest Firmware, now on OWC ThunderBay8 TB3 the backup is slow too so the problem cannot be on the Apple Thunderbolt3 Adapter.
Now I will try a other filesystem maybe the problem is the APFS.
Best regard
Roland
Promise Pegasus 2 R4 slow
