Re: [PATCH] Add extra statistics to explain for Nested Loop
Ekaterina Sokolova <e.sokolova@postgrespro.ru>
From: Ekaterina Sokolova <e.sokolova@postgrespro.ru>
To: pryzby@telsasoft.com, lukas@fittl.com,
pgsql-hackers@lists.postgresql.org
Date: 2022-02-02T21:59:03Z
Lists: pgsql-hackers
Attachments
- extra_statistics_v6.patch (text/x-diff) patch v6
- overhead_v0.txt (text/plain)
Hi, hackers. I apply the new version of patch. Justin Pryzby <pryzby@telsasoft.com> wrote: > I'm curious to hear what you and others think of the refactoring. Thank you so much. With your changes, the patch has become more understandable and readable. > It'd be nice if there's a good way to add a test case for verbose > output > involving parallel workers, but the output is unstable ... Done! Lukas Fittl <lukas@fittl.com> wrote: > I've briefly thought whether this needs documentation (currently the > patch includes none), > but there does not appear to be a good place to add documentation about > this from a > quick glance, so it seems acceptable to leave this out given the lack > of more detailed > EXPLAIN documentation in general. You're right! I added feature description to the patch header. > Whilst no specific bad cases were provided, I wonder if even a simple > pgbench with > auto_explain (and log_analyze=1) would be a way to test this? I wanted to measure overheads, but could't choose correct way. Thanks for idea with auto_explain. I loaded it and made 10 requests of pgbench (number of clients: 1, of threads: 1). I'm not sure I chose the right way to measure overhead, so any suggestions are welcome. Current results are in file overhead_v0.txt. Please feel free to share your suggestions and comments. Regards, -- Ekaterina Sokolova Postgres Professional: http://www.postgrespro.com The Russian Postgres Company
Commits
-
Fix wrong units in two ExplainPropertyFloat calls.
- f90c708a0486 14.0 cited