> pre-allocating during checkpoints. I've done a few pgbench runs, and > it seems to work pretty well. Initialization is around 15% faster, > and I'm seeing about a 5% increase in TPS with a simple-update > workload with wal_recycle turned off. Of course, these improvements > go away once segments can be recycled.
I've checked the patch v7. It applies cleanly, code is good, check-world tests passed without problems.
I think it's ok to use checkpointer for this and the overall patch can be committed. But the seen performance gain makes me think again before adding this feature. I did tests myself a couple of months ago and got similar results.