send vs send -p

[GreyGeek]

I've completed the installation of KDE Neon on my new HP 17cn1xx and set up my python3 development environment. I also moved @home into @ and commented out the line in fstab that mounts @home. Now it was time to make a backup.
The first backup was just a "btrfs send /mnt/snapshots/@todaysdate | btrfs receive /backup" For 79GB of data it took 39 minutes to a spinner plugged into a USB 3.0 port.
The second backup was a "btrfs send -p /mnt/snapshots/@yesterdaysdate /mnt/snapshots/@todaysdate | btrfs receive /backup" It took 48 seconds.

Of course, the amount of time that the incremental backup takes depends on the difference in the amount of changes between yesterday's snapshot and today's snapshot. I've got about another 25GB of data to install and by the time I finish the incremental backup will probably take around 90 seconds. I won't even attempt a non-incremental backup.

[jlittle]

btrfs incremental send/receive for backups has an advantage as well as that of saving time. The backup volume gets snapshots every time a backup is done, and so efficiently stores the state of the data at the frequency of the backup. For example, keeping weekly backups for a year may be quite feasible. This is much better than the classic weekly backups overwritten each month. If you include the occasional non-incremental in the mix, the backup volume will fill up more quickly.

[GreyGeek]

Yup, nice addendum!