On Thu, Nov 1, 2018 at 6:14 AM Michael Paquier <mich...@paquier.xyz> wrote: > > On Wed, Oct 31, 2018 at 01:09:53PM -0400, Robert Haas wrote: > > There's no rule whatsoever that a parallel worker can't write to the > > disk. pg_start_backup and pg_stop_backup have to be > > parallel-restricted because, when used in non-exclusive mode, they > > establish backend-local state that wouldn't be synchronized with the > > state in the workers -- namely the information that a non-exclusive > > backup is in progress. > > Okay, but likely we would not want to signal the postmaster > unnecessarily, no?
Right, but I think the question here is whether it is safe to execute this function in parallel workers? I don't see any meaningful use cases where anyone wants to run this via parallel workers even if it is safe to execute via them, but I think that is not how we decide parallel-safe property of any functions. -- With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com
