Yet another Hacker News

macOS 27 does not support CoreStorage volumes

49 points colejohnson66 2 hours ago 22 comments

throwaway27448 53 minutes ago | parent

For those of you who have never heard of this, it's macos's LVM. Why they didn't just refer to it as LVM is beyond me.

duskwuff 44 minutes ago | parent

> Why they didn't just refer to it as LVM is beyond me.

Because it isn't LVM, and giving it the same name as another similar-but-distinct technology would just make matters more confusing.

Grombobulous 42 minutes ago | parent

According to the Wikipedia article about CoreStorage, it seems like the primary/only use case was Fusion drives (hybrid SSD/HDD hardware).

The article says “It renders your expensive storage hardware completely useless.” but I’m really curious what that hardware could actually be. This seems like a pretty dead technology.

mikepurvis 8 minutes ago | parent

Sidebar, but as an end user, I remain annoyed that there isn't seemingly something that's a worthy successor to fusion drives.

Like I have an Unraid box with dual NVMe (RAID1) as the "cache" drive and a bunch of spinning disks as the "array", but it's also very manual, like torrents get downloaded first to cache and then a nightly job syncs them to the array. Feels like a real missed opportunity to not be able to have this kind of config transparently managed.

sysguest 29 minutes ago | parent

...like route 53? which is "dns configuration, but fancier"

zamadatix 24 minutes ago | parent

AFAIK "Route 53" was a net new name for such a product?

throwaway27448 5 minutes ago | parent

Does it not manage logical volumes?

vondur 15 minutes ago | parent

It doesn't really do everything that a real LVM does though. This was used to support those annoyingly bad Fusion Drives. They dropped them around 2020 I think.

throwaway27448 6 minutes ago | parent

> It doesn't really do everything that a real LVM does though.

It manages logical volumes. Any quibbling is a matter of degree.

exabrial 50 minutes ago | parent

MacOs 27 is a disaster. All of the sudden, I have 35% of a computer left to do any kind of work.

drooopy 45 minutes ago | parent

Among other signs of awfulness, macOS 27 (and 26 before it) half the battery life of my M1 Air, forcing me to stay on Sequoia for a 2nd year.

Grombobulous 38 minutes ago | parent

Couldn’t possibly have anything to do with a 6 year old battery I’m sure.

zbentley 7 minutes ago | parent

Not GP, but: I had replaced the battery on my M1 Max 6mo ago with an aftermarket part. On MacOS 26 that routinely gave about 5 hours of coding/browsing/active screen time (no audio or massive CPU load other than unit test runs).

Anecdotally, after updating to MacOS 27 2mo ago that time has been reduced by between a third and a half, doing the same kind of daily work on the exact same project, without major new apps installed or new always-open browser tabs.

I don’t know if it’s the OS’s fault directly or the fault of an app I use that interacts poorly with the new OS’s power management, but either one is damning. I’m not doing anything particularly weird.

otterley 45 minutes ago | parent

What does that mean?

sys_64738 34 minutes ago | parent

Maybe referring to the Apple Superintelligence being auto-added to macOS 27.

varispeed 32 minutes ago | parent

I'll wait for Apple Supremeintelligence in macOS 29

hmartin 46 minutes ago | parent

Also dropped support for FireWire drives, as I just found out the hard way.

traceroute66 27 minutes ago | parent

> Also dropped support for FireWire drives, as I just found out the hard way.

Erm... it was dropped in macOS 26 back in 2025 ?

https://www.techspot.com/news/108394-usb-killer-dead-apple-d...

flanz_10 26 minutes ago | parent

did you go from 25 to 27?

varispeed 33 minutes ago | parent

I upgraded and this system is a dumpster fire. Lags, random crashes, performance issues, random CPU spikes...