These tasks are available to instance operators:
rake mastodon:media:clearremoves uploads that have not been attached to any status after a while, you would want to run this from a periodic cronjobrake mastodon:push:clearunsubscribes from PuSH notifications for remote users that have no local followers. You may not want to actually do that, to keep a fuller footprint of the fediverse or in case your users will soon re-followrake mastodon:push:refreshre-subscribes PuSH for expiring remote users, this should be run periodically from a cronjob and quite often as the expiration time depends on the particular hub of the remote userrake mastodon:feeds:clear_allremoves all timelines, which forces them to be re-built on the fly next time a user tries to fetch their home/mentions timeline. Only for troubleshootingrake mastodon:feeds:clearremoves timelines of users who haven't signed in lately, which allows to save RAM and improve message distribution. This is required to be run periodically so that when they login again the regeneration process will trigger