WordPress database becoming huge. How to analyze and optimize it? fear of running out of memory

look at the size of my wordpress database tables:

are there simple ways to optimize it? I fear of running out of memory one day

maybe bad collation? how can I analyze what is eating up so much space in the posts and post meta tables?

One thing you can do to help reduce the amount of bloat is add a plugin that controls the number of previous revisions kept for Pages, Posts, etc (preferably one that allows for separate values for each type, such as last 5 revisions for pages and last 20 revisions for posts, or whatever.)

There are numerous plugins that handle this, check around https://wordpress.org/plugins/search/revision+control/ and similar