So … I did succumb, and I did purchase the Mac mini 4 Pro with 24Gb RAM and 500Gb internal SSD, and the Satechi Mac mini M4 Stand & Hub with SSD Enclosure with 2Tb of NVMe SSD storage which I liked the look of in the previous post
What have I learnt, what could I have done differently – if anything?
I’m pleased I purchased the Mac mini 4 Pro, I got a remarkably good discount on it (c.£300 from Amazon (breaking a golden rule), and was able to pay for it over 4 months at 0% interest. A good buy. The processor just swallows up anything and everything I throw at it, and with the 24Gb RAM, I believe I’ll be future proofed for quite a few years!
The SSD both internal and external (in the hub) however has caused some issues and consternation, which initially caused me to think I should have gone for a much larger internal SSD, but thankfully (as explained below) I’m now quite relaxed about that decision and 500Gb is definitely sufficient for my needs.
The Satechi Hub is not a Thunderbolt hub, and if I’d been prepared to wait (or pay a lot more for one that was not so aesthetically pleasing), the connection between the Hub and the Mac mini could have been faster – but to be honest the data transfer rate using the USB-C 3.2 Gen 2 (up to 10Gbps) has not proven to be a problem. The 2Tb Crucial NVMe SSD storage in the Hub is not being used intensively and so data transfer rate has not been a problem. The ports on the front of the Hub are all in use to serve music, movies and other stored media, and the SD-UHS-II card slot has been well used to import images from my camera.
The Mac mini’s Three Thunderbolt 5 ports are connected to the Hub, an external G’Drive SSD drive for Images, and a connection to two external G’Drive HD Time Machine and Carbon Copy Cloning drives. The Headphone jack connected to a pair of Logitech powered speakers. Magic!!!
[PS I treated myself to a Pioneer Blu-Ray Player as well because my old SuperDrive was not working with the new Mac mini hardware.]
Did I learn anything from the purchase? Well, yes – but it was nothing to do with the hardware!!
As I was editing images in Lightroom Classic, I discovered that I couldn’t save a Catalog Backup to a folder on my iCloud Drive. There was plenty of space for the file, so what could be going on?
It took me a couple of days to get to the bottom of the problem, and one that was quite unexpected.
The problem was that the System Data on my internal drive was growing to a ridiculous size, to the extent that there was not enough space on the Internal Drive of the Mac mini to do the save to the iCloud Drive. So, a couple of things had to be addressed. Why was the System Data growing so large, and should I review where some of my Lightroom files were being stored. This was the first thing to be considered.
I moved the Lightroom Classic Catalog Backups folder from the iCloud Drive to the external SSD drive in the Hub, I also reviewed all the other peripheral files and folders that Lightroom was using and either moved them to the Internal SSD on the Mac mini, or to the External SSD in the Hub.
The folders on the external SSD in the Hub – none of these require “fast” access and so are “happy” to sit on an external drive with data transfer rates still at up to 10Gbps.
These folders are located on the internal SSD of the Mac mini and are ones which could benefit from the fastest data transfer rates.
It is also important to make sure you’ve changed all the preferences in Lightroom Classic to match the “new” configuration …
So that’s got Lightroom Classic sorted to give me the best performance on the new kit, but still I had an issue with System Data in General > Storage on the Mac mini. For a while I thought “shall I just upgrade to Tahoe (from Sequoia) and perhaps it’ll go away, but having upgraded my Mac Book Pro to Tahoe I was astonished to see that even with 2Tb of Internal SSD storage, System Data was eating as much it could of that storage. Obviously something wasn’t right.
The solution which I discovered eventually after extensive use of Perplexity was counter-intuitive and one that I would never have worked out.
I needed to switch-off synchronising of my Desktop and Documents Folders – this meant some re-organisation of file store which was in itself long overdue, and then switch on Optimise Mac Storage!!!
Surprisingly System Data will gobble-up local disk storage if you switch this off. Switching it on gets everything back into a sensible state of order.
So … I applied these settings to both the Mac mini and the MacBook Pro (even though it had loads of Internal SSD space), and System Data shrunk on both systems to a manageable level.
Who’d have known that! Thanks Perplexity.
[Addendum: After upgrading the Mac mini 4 to Tahoe this morning (15/12/2025) the System Data shrank again to c.67Gb – this was also recommended in the Perplexity threads as a “if the above doesn’t work … try a re-install”]