Citus 11.3 is out! Now with tenant statistics. Read all about it in Marco's 11.3 blog post. 💥
Reducing replication lag with IO concurrency in Postgres 15
PostgreSQL 15 improves crash recovery and physical replication performance of some large and very busy databases by trying to minimise I/O stalls. A standby server might now have an easier time keeping up with the primary.
How? The change in PostgreSQL15 is that recovery now uses the
maintenance_io_concurrency setting (default is 10, but you can increase it) to decide how many concurrent I/Os to try to initiate, rather than doing random read I/Os one at a time. With big and busy databases, when I/O concurrency increases, replication lag can be reduced.