Can't test boot drive because it is set to "read only".

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Level 1

14 points

Can't test boot drive because it is set to "read only".

I'm getting constant beach balls with my relatively new M2 Mac Mini, although sometimes I can have an hour or so of ultra-fast performance with no impediments. In the previous 16+ years with various [way slower] Intel Macs, I've never experienced anything remotely like this. I'm trying to determine the problem, so am running BlackMagic Disk Speed Test. But when I choose the internal Mac Mini drive, I get an error message saying that is is read only. When I get info on this drive, "system" is set to Read & Write but both "wheel" and "everyone" are set to Read only.

Is this the default state and I shouldn't mess with it? I have external drives so it isn't like I specifically need to write to this boot drive, although obviously various things DO get written to it (like when an application is installed or when an application quits and the preference file is updated). Is this all "system" stuff?

Mac mini

Posted on Nov 5, 2024 8:54 AM

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Answer 1

Mac Jim ID

Level 7

26,447 points

Nov 5, 2024 3:50 PM in response to zerobeat

That is expected behavior of Blackmagic Speed Test on the boot drive when a folder has not been selected. As already been suggested, select the Downloads folder or actually any user folder. The System partition is not writable.

For the issue of constant beachballing, I would recommend posting the free EtreCheck report using the Additional Text option when posting. The report contains no personal information. It sounds like you may have third party processes launching at startup that is causing a conflict and those will be able to be identified in the report. The most common categories of apps where this has been seen are:

Cleaners (especially CleanMyMac)
Optimizers
AntiVirus
VPN

How to use the Add Text Feature When Post… - Apple Community

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Answer 2

zerobeat Author

Level 1

14 points

Nov 5, 2024 7:41 PM in response to Mac Jim ID

EtreCheck report

Thanks. I just did Etrecheck.

Some notes on its findings:

1) The "unsigned" software it found are from companies I trust and have been using for many years on other Macs.

2) I only have 8GB RAM, but in the first 3 months of me owning this computer I didn't experience this problem AT ALL, even when loading up a ridiculous amount of apps trying to bring to computer to its knees, which I could, but it wasn't beach balls but rather an actual message saying I'm running out of RAM. I get beach balls now with just one application open, or none (like trying to open a folder in the Finder).

3) I only have a 256GB internal boot drive (and external Thunderbolt HDs for data). The boot drive has 26GB free, basically the same amount since I first installed everything I needed to several months ago. I do NOT use the boot drive for storage at all. All folders (like pictures, documents, music etc...) are aliased to an external drive (SSD RAID).

3) Sharing risk: the beach balls happen even if I unplug the Ethernet cable (and I don't have WiFi or Bluetooth activated ever).

4) I don't use any cleanup or antivirus or vpn or optimizer software. Mainly Logic Pro and Music (formerly iTunes).

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Answer 3

Nov 5, 2024 11:58 PM in response to zerobeat

Your boot drive has too much on it.

10% free is not good . . . you should be aiming for at least 20%.

To get round the tiny SSD I have my M2 booting off a 1TB USB 3.0 SSD and surprising as it may sound, the computer performs every bit as fast (within 1%) as using the internal. Obviously copying huge files takes longer but that's the only downside.

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Answer 4

HWTech

Level 9

60,650 points

Nov 7, 2024 1:33 PM in response to zerobeat

I agree with @Ian that having just 24GB of Free storage space on the boot drive is part of the problem. 24GB is the bare minimum of Free space needed for the normal operation of macOS just for basic use of macOS. Other workloads require more Free space (ignore the "Available" storage value shown everywhere in macOS since it is very misleading)....the Free space is only shown within Disk Utility and System Profiler.

I think your 8GB of memory may also be part of the problem. While your memory usage at the time you created the EtreCheck report is Ok, I'm guessing you are running low on memory as well when you are on your more intensive workloads. Most people should have a system with at least 16GB of memory.

Another concern is the mention of qbittorrent app. BitTorrent use can easily impact system performance & chew up your already limited system resources. I skipped the installed software list since I am not a macOS software expert, so I leave that analysis to others.

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