[riedel]

I wonder why EC2 is so slow on snapshots. We use CEPH internally and if we wanted we could export the diffs [0] (we use proxmox backup instead). Snapshots always felt blazing fast (I still often forget to do them, need a solution to trigger them from the guest)

[0] https://ceph.io/en/news/blog/2013/incremental-snapshots-with...

[hanwenn]

IIUC, on EC2, the disk (EBS)is one service, and snapshots are in another service (S3). Taking a snapshot involves copying the entire disk to S3, while restoring a snapshot pages blocks in from S3 as the VM accesses the disk.