On 1/1/19 6:48 PM, Pavel Stehule wrote: > > > út 1. 1. 2019 v 18:39 odesílatel Tomas Vondra > <tomas.vondra@2ndquadrant.com <mailto:tomas.vondra@2ndquadrant.com>> napsal: > > Attached is v4, changing how GUCs are picked for inclusion on the query > plans. Instead of picking the GUCs based on group and/or explicitly, a > new GUC_EXPLAIN flag is used for that. > > I went through GUCs defined in guc.c and marked those in QUERY_TUNING* > groups accordingly, with the exception of default_statistics_target > because that seems somewhat useless without showing the value used to > actually analyze the table (and/or columns). > > I've also included a couple of other GUCs, that I find to be relevant: > > - parallel_leader_participation > - max_parallel_workers_per_gather > - max_parallel_workers > - search_path > - effective_io_concurrency > - work_mem > - temp_buffers > - plan_cache_mode > > > when plan_cache_mode is auto, you know maybe too less executed query. > Maybe you can read somewhere if plan was custom or generic. >
This patch is about showing GUCs, not such additional internal info. Also, you'll see the plan actually used.
I understand to your goal, and I understand so collecting some data inside can be hard or impossible.
But if you collect a data important for understanding to planner behave/decision, then some important information is inside plancache too. - and now it is not visible from user space.
It is just my note - so not only GUC are interesting - nothing more.
> > I think this covers the interesting GUCs pretty well, although perhaps I > missed something. > > > seq_page_cost, random_page_cost, from_collapse_limit, > join_collapse_limit, ... enable_*** >
All these GUCs are included, of course.
ok - thank you for info.
Regards
Pavel
-- Tomas Vondra http://www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
