Kevin Grittner <kgri...@gmail.com> writes: > On Mon, Apr 10, 2017 at 9:28 AM, Tom Lane <t...@sss.pgh.pa.us> wrote: >> I notice that the safe-snapshot code path is not paying attention to >> parallel-query cases, unlike the lock code path. I'm not sure how >> big a deal that is...
> Parallel workers in serializable transactions should be using the > transaction number of the "master" process to take any predicate > locks, and if parallel workers are doing any DML work against > tuples, that should be using the master transaction number for > xmin/xmax and serialization failure testing. Right, but do they record the master's PID rather than their own in the SERIALIZABLEXACT data structure? Maybe it's impossible for a parallel worker to acquire its own snapshot at all, in which case this is moot. But I'm nervous. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers