The current bgwriter_lru_maxpages value limits the background writer
to a maximum of 4MB/s. If one imagines shared_buffers = 8GB, that starts to seem rather low, but I don't have a good feeling for what a better value would be.
I don't quite understand the point of bgwriter_lru_maxpages in the first place. What is it supposed to protect us from?
I wonder if that isn't an artefact from when the checkpointer was the same process as the background writer, to prevent the background writer functionality from starving the checkpointer functionality.
