Greg Stark <[EMAIL PROTECTED]> writes: > Tom Lane <[EMAIL PROTECTED]> writes: >> The main problem with this is knowing which files need to be fsync'd.
> Why could the postmaster not just fsync *every* file? You want to find, open, and fsync() every file in the database cluster for every checkpoint? Sounds like a non-starter to me. In typical situations I'd expect there to be lots of files that have no writes during any given checkpoint interval (system catalogs for instance). > I'm assuming fsync syncs writes issued by other processes on the same file, > which isn't necessarily true though. It was already pointed out that we can't rely on that assumption. > Or using aio write ahead as much as you want and then just make checkpoint > block until all the writes are completed. You don't actually need to rush them > at all, just know when they're done. If the objective is to avoid an i/o storm, I don't think this does it. The system could easily delay most of the writes until the next syncer() pass. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html