Advanced: Allowing User to Specify Compression Program

[davidlohle]

This ability would be nested away in aegis.json and not changeable via Aegis runtime. Perhaps built-in support for pigz and 7zip?

config value something like:
"compression-program": "tar czf {1} {0}",

where {0} is the directory to be compressed and {1} is the output so that a user could change it like so:
"compression-program": "tar cf - {0} | pigz > {1}",

[davidlohle]

Actually thinking about this further, this should be a core feature, but implemented such that a user doesn't have to manually edit config. Current thoughts:

pixz is an interesting solution. While I want backups to perform quickly to minimize server overhead during a backup, the panic of "OH GOD I NEED TO RESTORE, NOW" really hits when you're unzipping a .tar.gz for a single file because gzip doesn't provide indexing and you're sweating for twenty minutes with angry users. So I'm at this weird crossroad.

The common case is compression, and pigz excels at that. Compressing a MC server folder @ 5.33GB goes down to 3.5GB in both pixz and pigz, but pixz took 3m28s while pigz took 0m40s. That's a LOT shorter, but the decompression time for a single file (most restore cases) is instantaneous with pixz, while you have to decompress the whole tar with pigz. (which takes some time, and in the case of my 50GB+ server folders, each second feels like an hour off my life worth of stress)

Since the amount of times a person compresses a server folder vs. restoring from backup is heavily lopsided towards compression, I believe pigz is the better default option. As such, the current compression setup will look as follows:

pigz
gzip
zip
pixz
xz

in that order. Aegis will check the system for those installed programs and operate in that order. A user can switch between the various algos with a reconfig suiting their purpose.