Pegasus 32 R4 - ThunderBolt MB/s Speed Discussion - Intel Mac vs M1 Max, etc..

  • Last Post 08 January 2023
John Felske posted this 05 January 2023

I have recently taken on a Mac Studio M1 Max. Previously I was using (still do) a Intel 27" iMac. Mac Studio has been nice, but I have noticed that reading from the Pegasus 32 R4 (I have Seagate 8TB IronWolf VN004's in it) has taken some time to get files to appear in Finder. 

This has lead me down a long road testing read and write speeds on this and other devices. Trying to get an idea of what others have experienced or have seen. 

In Short, The Pegasus 32 averages the image below (Intel Mac, Mac Studio and M1 Mini). Is this similar to what others are seeing?

I am finding the speeds to be very slow, especially in Mac OS Ventura. Just makes saving files or seaching brutal at times. I have tired to bounce back to Monterey on the Intel system and notice some better performance, but overall the speeds (MB/s) are similar. 

I have also tested a Pegasus2 R6, this system running TB2 has over all better numbers in the sequential are by 150MB/s - 250MB/s read and write vs the Pegasus32 on TB3. This really isnt making much sense.

Thoughts? Suggestions?



EDIT: Forgot to mention running RAID 5 


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Paul Blake posted this 05 January 2023

I have also just upgraded to Mac Studio M1 Max from a 27" iMac. I use the latest Ventura.

I purchased my Pegasus32 R4 from Apple as part of the system. It uses Toshiba HDDs.

These are my results below using Blackmagic's speed test.

I presume you are directly connected to one of the thunderbolt ports on the back of the Mac Studio using the Pegasus supplied cable, and not the USB ports on the front?



John Felske posted this 05 January 2023

Hi Paul, Thanks for the reply. 

I went to the BM speed test to get comparable results. They are below. 

I have used multiple TB3 (and even TB2) cables to test. and yes I am plugging into the TB ports on the back (differnt combos, etc..)

Seems I am in the same area as you are. One thing I am struggling with, and I have seen others on reddit and that say similar, is that reading seems to be a bit weird overall and sluggish. Not saying this is a Pegasus issue, but more of a Ventura issue with external drives. Hence why I was curious what others might be seeing in terms of speeds. 

For example, lets says I am in safari or chrome and goto save a video or file, when I goto the Pegasus, if it is a list of files that is a decent amount it takes quite a long time to populate the list of files and folders. Way more than what I was seeing with my intel Mac with the similar system. I guess I am going to have to chalk it up as a Ventura issue more than anything. Just ends up being cumbersome even when I have saved files over and over again, the process ends up the same. 

At times I am also seeing better load (read) times on TB2 system on the Pegasus2 R6. Just ends up strange on how this Studio is functioning.

Curious if you happen to see the same "issues" or if it is performing as expected similar to your Intel Mac. 

Thanks again! 



John Felske posted this 08 January 2023


I have been messing more with the read speeds within Ventura. I don't feel it has to do with external drive issues outside Finder just seems to struggle with accessing them and "loading" at times. 

I deleted my finder.plist and noticed that if I just use finder everythign seems fine and very little loading unless a lot of files. Where the trouble appears to lie is when attemping to save files or download from Safari or Chrome and picking folders to access within external drives, in this case the P32. For whatever reason finder just takes for every to load folders that have a decent amount of files. Don't know what to make of this really, but I am hoping a lot of this gets resolved on next update from Apple.

Going to keep working at it to see if I can figure out any fixes.