On 01/11/2015 11:27 AM, Stephen Frost wrote: > * Robert Haas (robertmh...@gmail.com) wrote: >> On Thu, Jan 8, 2015 at 2:46 PM, Stephen Frost <sfr...@snowman.net> wrote: >>> Yeah, if we come up with a plan for X workers and end up not being able >>> to spawn that many then I could see that being worth a warning or notice >>> or something. Not sure what EXPLAIN has to do anything with it.. >> >> That seems mighty odd to me. If there are 8 background worker >> processes available, and you allow each session to use at most 4, then >> when there are >2 sessions trying to do parallelism at the same time, >> they might not all get their workers. Emitting a notice for that >> seems like it would be awfully chatty. > > Yeah, agreed, it could get quite noisy. Did you have another thought > for how to address the concern raised? Specifically, that you might not > get as many workers as you thought you would?
Wild idea: What about dealing with it as some sort of statistic - ie track some global counts in the stats collector or on a per-query base in pg_stat_activity and/or through pg_stat_statements? Not sure why it is that important to get it on a per-query base, imho it is simply a configuration limit we have set (similiar to work_mem or when switching to geqo) - we dont report "per query" through notice/warning there either (though the effect is kind visible in explain). Stefan -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers