On Tue, Jul 23, 2019 at 7:29 PM Tom Lane <t...@sss.pgh.pa.us> wrote: > Parallel workers aren't ever allowed to write, in the current > implementation, so it's not real obvious why they'd have any > WAL log files open at all.
Parallel workers are not forbidden to write WAL, nor are they forbidden to modify blocks. They could legally HOT-prune, for example, though I'm not positive whether they actually do. The prohibition is at a higher level: they can't create new tuples or delete existing ones. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company
