Add expire time / garbage collect (to limit disk space)

[ppenguin]

Is your feature request related to a problem? Please describe.
Disk usage balloons over time, many older modules are not needed anymore but are eating up disk space.

Describe the solution you'd like
Functionality that cleans up (deletes) modules from the cache that were downloaded (longer than) x ago or (even better/preferred) were last requested longer than x ago.

[omartrigui]

@ppenguin Out of curiosity, which storage backend are you using, and what size did you hit? Also, how many repos are involved and how long did it take to reach that size?

[DrPsychick]

I guess the simplest solution would be to wipe the storage, but if you have any repos in your Athens that aren't available upstream anymore, they would be gone, so that needs to be validated first.

[ppenguin]

@ppenguin Out of curiosity, which storage backend are you using, and what size did you hit? Also, how many repos are involved and how long did it take to reach that size?

I'm using seaweedfs via CSI (running athens under nomad), but I found out since that the ballooning backing store of my seaweed volumes was caused by its default journalling strategy. I.e. if I don't cleanup the journal via a cron job, storage consumption grows to many multiples of the actual data. So athens was not the main issue here.