As I make a full clone of a VMware Workstation VM in just under 9 minutes, I'm reminded that the same thing would take about 1 second on macOS.

But hey, I hear the Windows peeps are working on cool things like software that scrapes your screen in the background as you use it. 😂

@wdormann I don't think that's a real copy (as in duplicated bits for a true full clone) though.

@buherator
CoW copies are no less real than copies that duplicate every single bit.

@wdormann (Morpheus voice) "How do you define 'real'?" But yeah, I get it, CoW is nice.

@buherator
I consider "real" in this case as in I can use it immediately, and anything I do with this VM clone is completely independent of the original. 😂

@wdormann
Oh, does macos have copy on write? Neat.

It does look like Windows added it for w11 24h2 and server 2025 but only on ReFS. Dunno if it's quite as easy though.
https://learn.microsoft.com/en-us/windows-server/get-started/whats-new-windows-server-2025#block-cloning-support

@FritzAdalis
If Microsoft indeed "added it" with 24H2, it's still not ready to use.
e.g. you cannot choose ReFS at install time. Even if you do custom partitioning, you only get to control the size of the partition.

When you install Win11 24H2 (Or Server 2025), you get NTFS. Even if you add an additional disk, you get the choice between NTFS and FAT32. 🤷‍♂️

@wdormann
Yeah, I guess ReFS is still the unloved stepchild. Oh well.

@FritzAdalis @wdormann Block Cloning on refs is actually available since ws2016 (I guess one needs to manually use fsctls there). But yeah, IMO they could just gradually transition such features to ntfs instead.

@sixtyvividtails @FritzAdalis
I was able to set up a Server 2025 machine with a second disk that was ReFS.
And it does indeed to CoW file copies by default in the GUI file manager like macOS introduced 7 years ago.

Baby steps... 😂

@wdormann @sixtyvividtails
I saw someone released btrfs drivers for Windows, maybe that's the way forward...

@FritzAdalis @sixtyvividtails
Sounds terrifying. 😂