On Mon, Apr 10, 2017 at 9:28 AM, Tom Lane <t...@sss.pgh.pa.us> wrote: > Thomas Munro <thomas.mu...@enterprisedb.com> writes: >> Here's a pair of draft patches for review:
Thanks. > Pushed with cosmetic improvements. Thanks. > 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. If either of those rules are being violated, parallel processing should probably be disabled within a serializable transaction. I don't think safe-snapshot processing needs to do anything special if the above rules are followed, nor can I see anything special it *could* do. -- Kevin Grittner VMware vCenter Server https://www.vmware.com/ -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
