I had a desire to enable compression after the fact on some shares. Synology (As of DSM 6.0) doesn’t have the facility to modify the compression settings of a folder after the initial creation – and perusing the forum, it seems you can’t enable compression at all on the /homes location.
Much discussion orbits the topic of chattr, how it isn’t installed and how to go about installing it. I have a way to do it without installing anything! btrfs-progs is already installed 😀
SSH into the device, and issue the command (as root)
btrfs property set /volume1/homes compression lzo
The btrfs command gives you plenty of other options to explore – perhaps best as a non-root user. Now to find a built-in for disabling Copy of Write.