While running backups of the site, I'm noticing that there are some very large private message attachments, in some cases from a very long time ago, still on the server. (If I'm not mistaken, they're only removed when everyone has deleted the message - including the sender if they've saved it in their Sent Items).
These do add to site storage costs, and seeing as they're unlikely to be downloaded again (compared to those in regular posts, which new users might want to download), I'm considering whether to implement a system where PM attachments are removed from the server if:
- They've been downloaded at least once
- They haven't been downloaded within the last 30 days (but I do need to check whether SMF actually tracks this; I don't think it does)
- They've over a certain size, probably around 200KB (as small files such as levels have a negligable impact on storage costs; I'm referring to the larger, multi-MB files here)
This would not affect the messages themself, only the attachment. I could possibly also look into having the site send a warning message before this happens, if people are worried about possibly-important attachments they may have in their older messages.
(One alternative that people may suggest is limiting the total size of PM attachments a single user can have; I don't like this idea, as I'm perfectly fine with someone having multiple large attachments in their inbox/outbox; if they're there because they're actually being sent to the person, and not just sitting there, taking up space, from a PM several months ago.)
Implementing such a measure could also mean I'd be more comfortable with increasing the size limit a bit; this has been mentioned in the past.
Just to be clear, no such system has been implemented yet, and it will not be implemented without a warning significantly in advance. It's just something I'm considering.