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CLOD-HOPPER

macrumors regular
Original poster
Oct 10, 2015
124
5
I know that something similar to this question has been asked and answered previously, but there is a slight difference of circumstance in my question.

Using Open Core Legacy Patcher, I installed Monterey on my early 2009, 24-inch iMac. It seems to have been successfully installed, even though it was installed on a spinning platter hard drive. Emboldened, I then paid to have a SSD installed, and thought that the Monterey installation could be easily cloned over to the SSD. I used Carbon Copy Cloner, but it did not work, and I now realise that Monterey will need to be installed all over again, on the SSD. (Also, since trying the cloning, Monterey will not boot any more.)

My question is: Ought the SSD to be formatted as APFS, or should it be Mac OS Extended (Journalled)? And if APFS, would it be possible to drag files etc over from folders that exist on a data-storage-only partition? (This partition exists on the spinning platter hard drive.)

With thanks in hopes of some informed advice,
C.H.
 

theMarble

macrumors 6502a
Sep 27, 2020
967
1,352
Earth, Sol System, Alpha Quadrant
Monterey (and every release since Mojave) physically cannot be installed onto a drive formatted as HFS+ (Mac OS Extended (Journaled)). APFS is a requirement.

The benefits of APFS are that it can read/write several times faster than HFS+, as it has been solely optimised for SSD's. That's why performance is so bad on old mechanical spinning drives. Also, because of the way it handles data, you get more storage space than you would with HFS+.

The downside of APFS is that it cannot be read or written to by older versions of OS X/macOS, prior to High Sierra.
 

TheShortTimer

macrumors 68030
Mar 27, 2017
2,788
4,912
London, UK
That's why performance is so bad on old mechanical spinning drives.

Which was why even spinner die-hard me, installed an SSD on a MBP that runs Ventura.

Also, because of the way it handles data, you get more storage space than you would with HFS+.

I didn't know that. Interesting!

The downside of APFS is that it cannot be read or written to by older versions of OS X/macOS, prior to High Sierra.

Yes, I've seen this on my 2010 MBA that has a triple-boot of Snow Leopard, Mojave and Catalina. Snow Leopard is unable to see the Catalina partition. It's a shame that no-one has written a driver/patch to remedy this. Ah well.
 

theMarble

macrumors 6502a
Sep 27, 2020
967
1,352
Earth, Sol System, Alpha Quadrant
I didn't know that. Interesting!
Yeah, I remember that it was one of the big features of APFS when it was announced.

I'm not too well-versed on filesystems work, but I believe it has to do with it supporting 64-bit index nodes. HFS+, being released in 1998, had no support for it. The horrid performance on spinning drives has something to do with this as well, if I understand it correctly.

From Wikipedia:
Enumerating files, and any inode metadata in general, is much slower on APFS when it is located on a hard disk drive. This is because instead of storing metadata at a fixed location like HFS+ does, APFS stores them alongside the actual file data. This fragmentation of metadata means more seeks are performed when listing files, acceptable for SSDs but not HDDs.

Apple has published a white-paper on APFS, if you're interested in how it works. I can't make heads or tail of it though.
 

CLOD-HOPPER

macrumors regular
Original poster
Oct 10, 2015
124
5
The downside of APFS is that it cannot be read or written to by older versions of OS X/macOS, prior to High Sierra.
I note what you say about APFS, theMarble. However, my question was not about reading or writing to an old version of Mac OS, from an APFS-formulated drive (I shall not use El Capitan on the old iMac). It is a separate STORAGE-ONLY partition from which I might want to drag files into the SSD, running Monterey, and edit them. Or I might want to look at a file on the storage-only partition, double-click on it, and open and edit it, leaving it where it is stored (i.e.in a partition that has no operating system whatever on it).

Would that work?
C.H.

PS: As I stated earlier, I did instal Monterey on a spinning platter H.D, and it worked OK. (Perhaps this anomaly was because I used Open Core Legacy Patcher, to install it.) There is an update on this. I decided to go ahead and install Monterey on the SSD that I had installed on my old iMac. You may find this hard to believe, but I am finding that this installation does not run as well as it did on the spinning platter H.D! Also, it is not any faster. The cursor freezes occasionally, and I cannot connect to the Internet by WiFi. (Luckily, I have another Mac, running High Sierra, so I can use the internet). The WiFi keeps on reporting that the network that I ask to join "cannot be found". If anyone can offer any useful advice about this, it will be gratefully received!

The WiFi problem has been resolved. I spoiled things by attempting to join a network before applying post-install extras.

Another admission (to theMarble) is this: a bit late in the day, as it were, I discovered that OCLP does its own partition-formatting, even though the partition may start out as HFS+. It then re-formats it to APFS.
 
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