Mac Studio M1 Ultra, Network and Speed problems

  • Last Post 30 January 2023
Vogelsänger Studios posted this 30 January 2023

Hello we have 4 edit setups at our office

(2x Mac Studio M1 Ultra -> Pegasus3 R8 and 2x Mac Pro 2019 -> Pegasus2 R8).

We've been using Promise raids for a couple of years and since adding two Mac Studios as the main workstations

and updating from Catalina to Monterey (all system are on the exact same version) we have been experiencing

many performance problems to the point that projects wont even load up for hours and working from an external SSD is that much faster.


All four workstation are connected over LAN Network and the raids are shared and can be accessed via Finder.

That used to work flawlessly and even simultanious editing was no problem but now the projects crash as soon as another device is trying to communicate.

On the M1 Macs the issue is a lot more coomon though. When the raid is connected the whole system feels dragged and gets hickups. Disconnecting the Thunderbolt 3 cable actually increases the whole system performance.


Raid speeds on the M1s vary from w: 90mb/s r: 150mb/s to w: 600mb/s r: 600mb/s but its always all over the place.


I found out that after restarting the system the speeds would be very low. Goind into Promise Utility and changing the Cache Policy from "ReadAhead/WriteBack" to anything else, saving, going back into settings and switching back to "ReadAhead/WriteBack would result in the best perfomance. Although it wont last for long and the speeds will be all over again after some time.


I hope to find help in this forum, we are right now editing new projects from external SSDs and thats really impacting our workflow.



Greetings from Germany!

R P posted this 30 January 2023


Hopefully the winter in Germany is not too cold.

First some general advice. Please use the appropriate drivers and Promise Utility from the Pegasus32 downloads. They are backards compatible with the Pegasus 2 and Pegasus3. Pegasus 2 and 3 drivers are Intel only and won't work on an M1.

Second, please make sure you are using the latest user space driver on the M1.

Lastly, for M1 MACs you need to make sure the Pegasus 2 units have the latest firmware.

The latest Promise Utility will give a CRC error if you try and update Pegasus2 firmware, this will be fixed next release, but for now to update the Pegasus 2 firmware please use a slightly older Promise Utility, v4.06.0000.01 will work.

I am not aware of any firmware issues with the Pegasus 3, but it won't hurt to update to the latest version of the Pegasus 3 firmware.