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+====== Force SSD Optimizations on Format ======
+Some devices are improperly detected on Linux as being rotational (ie: hard-drive with spinning disks) when, in fact, the device is an SSD (flash type) device. ''mkfs.btrfs'' checks:
+<code>
+/sys/block/DEVICE/queue/rotational
+</code>
+where ''DEVICE'' is a block device (''sda'', ''sdb'', etc...) and if the contents of that file is ''1'', then ''mkfs.btrfs'' considers that the device is rotational and disables SSD features.
+In case ''mkfs.btrfs'' disables SSD features but you are certain that the device is an SSD, you can simply:
+<code bash>
+echo 0 >/sys/block/DEVICE/queue/rotational
+</code>
+where ''DEVICE'' is the block device, in order to make the kernel treat the device as a non-spinning disk.
+After that, you can issue ''mkfs.btrfs'' with your favourite options and ''mkfs.btrfs'' will detect the device as an SSD.
+====== Snapshot and Recovery ======
+btrfs supports snapshotting at the volume level such that individual files cannot be backed up but rather a snapshot of the entire volume has to be taken. Subvolumes typically exist on the same filesystem as a sub-directory and in order to take a snapshot, a snapshot directory has to first be created using the command line:
+<code>
+btrfs subvolume create /mnt/volume/.snapshots
+</code>
+where:
+  * ''/mnt/volume'' is the path where the btrfs filesystem is mounted,
+  * ''/mnt/volume/.snapshots'' is the path where the subvolume will be created
+After which a snapshot of the volume can be created, for example, by issuing:
+<code>
+btrfs subvolume snapshot -r /mnt/volume /mnt/volume/.snapshots/20250811
+</code>
+where:
+  * ''-r'' stands for read-only,
+  * ''/mnt/volume'' is the path where the btrfs filesystem is mounted,
+  * ''/mnt/volume/.snapshots/20250811'' is the subdirectory that will store the snapshot
+Snapshots are instantaneous because btrfs maintains a link between inodes such that the snapshot file represents a careful set of links rather than a complete copy of a file.
+Restoring a file does not require any special command but rather copying the file using regular tools should be sufficient. For example to restore ''/mnt/volume/writeup.docx'' from the snapshot folder ''/mnt/volume/.snapshots/20250811'', simply copying it over is sufficient:
+<code bash>
+cp /mnt/volume/.snapshots/20250811/writeup.docx /mnt/volume/
+</code>
+To delete the volume-level snapshot after that, issue:
+<code bash>
+btrfs subvolume delete /mnt/volume/.snapshots/20250811
+</code>
+which should delete the entire folder ''/mnt/volume/.snapshots/20250811''