Will deleting old, unused characters help free up server space?

[Catwho]

From what I understand: Offline character data is stored in a different place (the database) than the online character data (the Random Access Memory or RAM.) The world server loads the character data from the database into the world server's RAM, where it exists in real time along with the rest of the actual game world itself. It syncs your character's data back to the database about every 15 seconds, but the "you" that is logged into the server is live and active in the world instance only when you are actually logged in.

Log off, and it saves your character data to the database and removes the character from the RAM of the server, freeing up another login slot.

Database storage doesn't seem to be an issue; the issue is how many active character sessions can live in the server's RAM at any given time. So deleting offline characters will not help.

Source: I work in software development. Our software is capped at about 1000 concurrent sessions, but we have tables with millions of rows in the database that exist without any interference to the system servers.