Sure I don't expect my application to have 14k RPS all the time. However, some spikes can happen, and it can leave you with a large WAL file which doesn't shrin

Sure I don't expect my application to have 14k RPS all the time. However, some spikes can happen, and it can leave you with a large WAL file which doesn't shrink by itself by default. 14k RPS is the maximum my PC could pull off, I think it can happen with a more modest RPS. I ran the stress test with 12 parallel threads, so technically it can happen with just 12 RPS too, if your read or write transactions take a lot of time each (say, it has to read a large table, or you forgot to add indexes, or write transactions update many rows). In fact, a single open read transaction already can trigger checkpoint starvation. Also, it's not only about HTTP requests, my application is event-driven so a few event handlers processing events in the background can easily trigger it, too. A system can accidentally produce many events without having a lot of user requests (say, you forgot to batch events and generate N separate events for N items).