The consequence of disabling fsync is the same regardless it’s a local or remote disk: you should always guarantee your WAL writes. If you achieve a quick win for better writes, I would say keep your WALs on the local drive and write the rest into ceph. Since you can cap total WAL size you don’t have to scale the local disk ever but you will have to rescue your drive in case of failure if you want your WALs back. On Sat, 8 Feb 2025 at 02:03, Petr Holubec <petr.holubec@dcore.cz> wrote:
We are evaluating pros and cons of running postgresql backed by ceph. We know that running pg on dedicated physical hw is highly recommended, but we've got our reasons.
So to the question: What could happen if we switch fsync to off on postgre backed by ceph?
The increase of perfomance is huge, which is the reason we are considering it. Ceph pool is running on osds connected to controllers with batteries so we could mitigate power losses. What happens when an osd run out of space? Are there other considerations? _______________________________________________ ceph-users mailing list -- ceph-users@ceph.io To unsubscribe send an email to ceph-users-leave@ceph.io