It’s not “safe” or “unsafe”, there’s mountains of valid workloads which don’t require synchronous_commit. Synchronous_commit don’t make your system automatically safe either, and if that’s a requirement, there’s many workarounds, as you suggested, it certainly doesn’t make the setup useless.
Best, Pierre On Thu, Jul 24, 2025, at 21:44, Nico Williams wrote: > On Fri, Jul 18, 2025 at 12:57:39PM +0200, Pierre Barre wrote: >> - Postgres configured accordingly memory-wise as well as with >> synchronous_commit = off, wal_init_zero = off and wal_recycle = off. > > Bingo. That's why it's fast (synchronous_commit = off). It's also why > it's not safe _unless_ you have a local, fast, persistent ZIL device > (which I assume you don't). > > Nico > --