51 points colejohnson66 2 hours ago 23 comments

throwaway27448 59 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 51 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 48 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 14 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.

kstrauser 6 minutes ago | parent

I've gotta agree. I'm not sure what expensive storage hardware would be both relevant today and unable to migrate off CoreStorage. For example, my most expensive storage is a NAS with an iSCSI target, and it couldn't care less what blocks I write to it. If I had a CoreStorage setup on it, I could migrate the data to a new target and then reuse that space for something else. The hardware wouldn't mind, or even know, that I'd changed what's on it.

You mentioned old, obsolete Fusion drives. I'm having a hard time thinking of anything else where that'd matter, so you're probably right about that. AFAIK you can reformat those to use something other than CoreStorage if you're actually stuck using those boat anchors.

sysguest 35 minutes ago | parent

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

zamadatix 30 minutes ago | parent

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

throwaway27448 12 minutes ago | parent

Does it not manage logical volumes?

vondur 22 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 12 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 56 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 51 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 44 minutes ago | parent

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

zbentley 14 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 51 minutes ago | parent

What does that mean?

sys_64738 40 minutes ago | parent

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

varispeed 39 minutes ago | parent

I'll wait for Apple Supremeintelligence in macOS 29

hmartin 52 minutes ago | parent

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

traceroute66 33 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 32 minutes ago | parent

did you go from 25 to 27?

varispeed 40 minutes ago | parent

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