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Can't you use CoW to make the clone essentially instant? (I thought BTRFS supported it, but I'm not sure)

Edit: Okay, I did a bit of searching and if the image is a file (qcow2, say) I'm pretty sure you could just `cp --reflink=always old.qcow2 new.qcow2` and it would take way less than 30 seconds. (Again, assuming BTRFS; I guess ex. XFS has some sort of reflink support these days but I don't know)

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This isn’t about cloning an image, it’s the full running VM state, including memory.

? I was responding to

> A VM can be cloned and the clone started in seconds though this heavily depends on image / rootfs size so it’s likely more in the order of 30 seconds or so (number pulled out of thin air).

which is specifically about the disk side.

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