Reinstalling packages to get btrfs to compress the files?

Question

I recently upgraded most of my partitions to btrfs. I turned on compression in fstab, but it will only compress newly created files, which makes sense.
Lets say I have firefox installed. If I do pacman -S firefox, I assume it will actually rewrite the files and not just skip over ones that are already there, right?
Assuming this is the case, what would be a good way to reinstall all of my packages without screwing up the dependency tree?
Maybe I'll have to do two commands:
sudo pacman -S $(pacman -Qqe)
sudo pacman -S --asdeps $(pacman -Qqd)
Does that seem right?
Last edited by pogeymanz (2013-05-01 14:09:41)

Answer 1

lucke wrote:Maybe adding "-l 1" to the defrag command would assure all files are acted upon.
Wow, reading the man pages reveals some handy tricks! 
man 8 btrfs wrote:
filesystem defragment -c[zlib|lzo] [-l len] [-s start] [-t size] -[vf] <file>|<dir> [<file>|<dir>...]
              Defragment file data and/or directory metadata. To defragment all files in a directory you have to specify each one on its own or
              use your shell wildcards.
              The start position and the number of bytes to defragment can be specified by start and len. Any extent bigger than threshold will
              be considered already defragged. Use 0 to take the kernel default, and use 1 to say every single extent must be rewritten. You
              can also turn on compression in defragment operations.
Edit: Width formatting...
Last edited by WonderWoofy (2013-05-01 14:56:50)