Hardware and performance

I'm a bit mystified by your question. If you upload more files to your site (or run loads of automatic backups) then your file requirements will increase.

If you don't like it, you need to analyse *why* the file storage requirements are increasing so rapidly.

Have you looked into using dedup for at least your storage location for your course backups?

I do not know much about your situation, so I can only give very vague recommendations. I think this breaks down into two areas:

1. Generic web hosting concerns
2. Moodle-specific

For example: should you host many GBs of HD video directly using Moodle, or advise users to use a dedicated video platform (Vimeo or YouTube)? That's a general question for any web application, but there are specific ways you can address or prevent it in Moodle.

You might also want to look into:

• Course size plugin. Not a perfect measurement, but it can help you identify outlier courses.
  
• Are you saving a lot of automated course backups?
• What are the file size upload limits for your site, courses, and individual activities? https://docs.moodle.org/37/en/File_upload_size
  
• Are any of your database tables particularly large? Are you using any custom plugins that are misbehaving? I had a plugin that was writing millions of lines of event records to mdl_logstore_standard_log, and it turned out to be a pretty quick and reasonable fix once I showed it to my developer.