https://bugs.openldap.org/show_bug.cgi?id=10454
Issue ID: 10454 Summary: O_DSYNC is busted on macos Product: LMDB Version: unspecified Hardware: All OS: Mac OS Status: UNCONFIRMED Keywords: needs_review Severity: normal Priority: --- Component: liblmdb Assignee: bugs@openldap.org Reporter: pyry.kovanen@gmail.com Target Milestone: ---
LMDB relies on O_DSYNC for writing the meta page, unfortunately it doesn't work on macos. Previous discovery by the tigerbeetle guys: https://github.com/tigerbeetle/viewstamped-replication-made-famous#leaderboa..., some more context at https://x.com/jorandirkgreef/status/1532314169604726784.
I discovered this during benchmarking and was wondering why lmdb writes were twice as fast as macos as on linux.