MacOS Catalina has a dedicated system volume now

[seedylee]

Is it still possible to modify system launchctl daemons on catalina? The facial recognition in Mojave Photos has absolutely killed performance of my machine for months, and the only solution apple could offer was to disable Photoanalysisd after disabling SIP.

In any event it's unlikely I will move on from Mojave due to the amount of 32 bit software I still depend on, so I'm probably going to be a security sitting duck in any case.

 

[FarmerBob]

I've hard a dedicated volume for the OS since the late 90's. The main way to keep things safe. OS on one partition or drive, Apps and Files on another, Databases (aliased into the OS partition) on a third. That way when the OS hammers, and it will, all you have to do reinstall the OS and you are good to go. A minimal amount of lost info if not backed up. Plus Back Ups are so much smaller and for any reason I can recover in 10-15 minutes.

 

[verpeiler]

Hmmmm..... lemmmmeeeesssseeee here....

Since back to my earliest days of Mac'ing (late 80's), I've partitioned my drives so that the "System files" resided in their own partition.

I've ALWAYS kept my data on a separate volume (partition).
This made it fast and easy to backup my data, and if anything went wrong with the "system partition", the data partition was usually still fine.

And for years others told me what I was doing was unnecessary.

Well, well, well...!
Looks like Apple itself has finally come around to "my way of doing it".
That is -- segregate the OS files into their own "space".
Call it "a partition", or call it "a container", or call it whatever you like ("a rose by any other name...")
That's what they're doing.

Who had it right...?

Uh, users (especially on Windows) have been doing this like forever... Nothing special about it.

 

[bogdanw]

Is it still possible to modify system launchctl daemons on catalina? The facial recognition in Mojave Photos has absolutely killed performance of my machine for months, and the only solution apple could offer was to disable Photoanalysisd after disabling SIP.

With SIP disabled, launchctl unload -w /System/Library/LaunchAgents/com.apple.photoanalysisd.plist still works in Catalina 19A501i.

 

[dsemf]

This thread has been quiet lately. I found a very informative link at CCC that helped me understand the changes with APFS.

https://bombich.com/kb/ccc5/working-apfs-volume-groups

DS

 

[Skoal]

Can you still override Gatekeeper with right-click + open?

Yes

 

[Skoal]

I think doing this has broken a bunch of apps that require the tmp folder.
Tunnelbrick doesn’t work on Catalina at the moment. It doesn’t even seem to be able to install properly.

So you’re saying the name “tunnelbrick” is appropriate then?

 

[DuncanGarp]

Related to this topic.

I have 2 partitions setup on my internal drive. The first hosting Mojave and the second hosting Catalina.

• MaciIntoshSSDMojave
• MacIntoshSSDCatalina

On the Catalina Drive, it showing these 3 under /Volumes

1. MacIntoshSSDCatalina/
2. MacIntoshSSDCatalina - Data/
3. MacIntoshSSDCatalina - Data 1/

edit: along with the above, this one is included as well

• MacIntoshSSDMojave/

So my confusion are why there are 2 " - Data/" and " - Data 1/"

Anyone can explain this for me? Thanks.

 

[DuncanGarp]

Related to this topic.

I have 2 partitions setup on my internal drive. The first hosting Mojave and the second hosting Catalina.

• MaciIntoshSSDMojave
• MacIntoshSSDCatalina

On the Catalina Drive, it showing these 3 under /Volumes

1. MacIntoshSSDCatalina/
2. MacIntoshSSDCatalina - Data/
3. MacIntoshSSDCatalina - Data 1/

edit: along with the above, this one is included as well

• MacIntoshSSDMojave/

So my confusion are why there are 2 " - Data/" and " - Data 1/"

Anyone can explain this for me? Thanks.

An update on this.

It must have just been an anomaly. What I did was a fresh re-install and it seems to have just reset everything and now I only have a single "MacIntoshSSDCatalina - Data/" drive.

 

[gilby101]

I have 2 partitions setup on my internal drive. The first hosting Mojave and the second hosting Catalina.

Do you really mean 2 partitions or did you just add Catalina as a new volume in the APFS container?

Much safer (and less confusing) to put Catalina on a different drive (e.g. an external SSD).

 

[DuncanGarp]

Do you really mean 2 partitions or did you just add Catalina as a new volume in the APFS container?

Much safer (and less confusing) to put Catalina on a different drive (e.g. an external SSD).

Added a new volume on the same APFS container hosting Mojave. So 2 volumes on internal SSD (1) Mojave and (2) Catalina. I didn't have a spare external SSD to try, but I will soon.

 

[0906742]

How much ssd space is wasted on dedicated system volume? I have MBP 128GB and I'm wondering how big partition will be created for system. I guess you must leave there extra space to allow it expanding during use but I'd rather sacrifice as little as possible for that partition to avoid wasting any free space from that small ssd.

 

[glhaynes]

How much ssd space is wasted on dedicated system volume? I have MBP 128GB and I'm wondering how big partition will be created for system. I guess you must leave there extra space to allow it expanding during use but I'd rather sacrifice as little as possible for that partition to avoid wasting any free space from that small ssd.

One of the cool features of APFS is "space sharing" — multiple volumes can exist in the same container and share its space, growing and shrinking automatically. So, any loss of space because of the new system volume is extremely minimal.

 

[0906742]

That is good to know. Is it so clever that it dynamically expands the space it need while machine is running or does it do it periodically? About how much "extra" space it will reserve for system partition or is it going to be exactly what the files in that partition use?

 

[adrianlondon]

I'm no technical expert on this new thing, but my understanding is that it's just a logical partition - it's not real. It sits on the same actual partition as the other logical one. Think of it as simply a directory (with loads of hard links to the rest of the filesystem) that's marked read-only somehow.

 

[0906742]

OK. Sounds nice. I was a bit worried about how it works since I just got only 128GB machine.

 

[gilby101]

Partitions and volumes are not the same thing. Partitions are rigid, volumes are flexible. You only need 1 partition. That single partition contains 1 APFS container. The APFS container can hold multiple APFS volumes. The APFS volumes share all the space in the container. And each APFS volume expands and contracts as needed.

Having said that, putting two boot volumes on a 128 GB SSD is going to be very restricted. Have fun!

 

[0906742]

Having said that, putting two boot portions on a 128 GB SSD is going to be very restricted. Have fun!

I'm not sure I get what you mean by that? Am I going to be in troubles with Catalina when I have no issues with free space using Mojave? If 128GB is not going to be enough for Catalina, I don't get why Apple still sells new computers with 128GB. Anyway, I guess I did not get right what you meant.

I may or may not at some point consider running also Windows in my Macbook but I have external SSD already purchased and I will use that for it.

 

[gilby101]

I'm not sure I get what you mean by that?

Firstly, I have corrected two portions(!!) to two volumes.

What I meant was that 128GB is pretty small for one copy of the OS and some documents, photos, etc. Putting a second copy of macOS on there as well might be just a bit too much, even with the benefits of APFS volumes sharing the space.

I don't get why Apple still sells new computers with 128GB

Neither do I, except for those with very modest needs.

 

[0906742]

Firstly, I have corrected two portions(!!) to two volumes.

What I meant was that 128GB is pretty small for one copy of the OS and some documents, photos, etc. Putting a second copy of macOS on there as well might be just a bit too much, even with the benefits of APFS volumes sharing the space.

Sorry I'm must be stupid or something but I still did not get what you mean by second copy of MacOS? Do you mean if I wanted to have two different MacOS versions installed at the same time or what (I don't think I ever need more than the current one I use at the time)?
I realize in case I sometimes want to have Windows installed I will have problems with internal ssd size but for that I already have external ssd, so I could put it there but I have several Windows machines from desktops to laptops already, so I really don't see the reason for that now.

Neither do I, except for those with very modest needs.

Well, I out myself in that category since I got my MacBook just for being curious about having my first MacOS system to expand my current ecosystem from iPhone, iPad, AW and Apple TV.

Plus I did not want to pay extra 250 currency for the step up 256GB, the price difference is just not from this world considering I could buy 512 external ssd for under 100.

 

[gilby101]

Sorry I'm must be stupid or something

No you are not! I have gone back through this thread and I have been confusing your comments and those by DuncanGarp who does want to put two copies of macOS on the one disk.

You clearly (when I read it properly) are going to have Windows on a separate SSD. I am sure Catalina will take much the same space as Mojave when you are ready to upgrade.

Sorry about causing confusion.

 

[cBraunDesign]

This is great, thanks to everyone who contributed. Similar to other posters, I just like to hide all of the silly Apple apps like Chess and Launchpad from the Finder view to clean things up. These commands worked great.

Follow up question for someone who's relatively naive about this stuff: Is there anything we need to do to "reverse" the command that mounts the system volume as writable, similar to how we re-enable SIP after we're finished with the customizations?

EDIT: After rebooting, it appears the system volume is back to being read-only.