Before I start proposing solutions like all the posts above, a few additional questions:

1. Is it a lot or a little?

2. What has been the trend over the last week/30 days?

3. Does the Damus relay have any purging/archiving mechanism implemented?

4. What effect does database size have on relay performance?

5. Is the relay architecture scalable?

Do you want to write a longer article about the operation of Damus relay? Many of us would welcome it!