Hi, On 2017-10-08 18:36:23 +0200, Pavel Stehule wrote: > 2. Lot of used tables are pretty wide - 60, 120, .. columns > > Now, I am doing profiling, and I see so most time is related to > > ExecTypeFromTLInternal(List *targetList, bool hasoid, bool skipjunk)
Yea, that's known - I've complained about this a couple times. You could try whether the following master branch helps: https://git.postgresql.org/gitweb/?p=users/andresfreund/postgres.git;a=shortlog;h=refs/heads/simple_statement_perf That's just micro-optimization though, not a more fundamental solution. But for me it yields pretty nice speedups for cases with long tlists. > This function is executed in exec init time - in this case pretty often. > Although there are used few columns from the table, the target list is > build for columns (maybe it is bug) It's probably just the physical tlist "optimization". > 2. If is not possible to reduce the number of fields of target list, is > possible to store tupledesc template to plan? We should do that, but it's not a small change. Greetings, Andres Freund -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
