On Wed, Nov 11, 2020 at 9:57 PM Simon Riggs <si...@2ndquadrant.com> wrote: > Having said that, we did raise the checkpoint_timeout by a lot, so the > situation today might be quite different. A large checkpoint_timeout > could eventually overflow shared buffers, with the right workload.
FWIW Jakuk Wartak did manage to show a 1.64x speedup while running crash recovery of an insert-only workload (with a variant of this patch that I shared in another thread), albeit with aggressive tuning: https://www.postgresql.org/message-id/VI1PR0701MB6960EEB838D53886D8A180E3F6520%40VI1PR0701MB6960.eurprd07.prod.outlook.com > We don't have any stats to show whether this patch is worthwhile or > not, so I suggest adding the attached instrumentation patch as well so > we can see on production systems whether checkpoint_timeout is too > high by comparison with pg_stat_bgwriter. The patch is written in the > style of log_checkpoints. Very useful. I've also been wondering how to get that sort of information in hot standby.
