Ever since PostgreSQL 11 we have JIT (Just-In-Time compilation).
Information about JIT is displayed in explain analyze plans, but up to this moment, explain.depesz.com didn't display it properly. But not anymore. Thanks to release 1.05 of Pg::Explain and subsequent change in templates for the site, you can now see nice JIT info.
Hope you'll find it useful 🙂
Just committed some new changes to explain.depesz.com.
The less visible is that, in case of plans generated by plain EXPLAIN (without ANALYZE), site will no longer show “actual time=.. rows= loops=", which was clearly bogus info.
The more visible is that if you add query to your plan, you can also have it reformatted to (hopefully) nicer format, shown in “REFORMATTED QUERY" tab. For example, take a look at this example.
Reformatting is done using pgFormatter library by Gilles Darold.
I picked this library for the very simple reason – it's in Perl, just like explain.depesz.com site, which made using it a breeze.
Quite a lot of people have been bugging me about it, and finally got some time, and worked on it.
Long story short – it works.
You can add your query below plan (in separate text area), and then it will be displayed as one of tabs
For example, check this plan.
It also works sensibly-ish, if you want to obfuscate your plans, as you can see here.
In case you're interested in technical details …
Continue reading You can now add query to your plan on explain.depesz.com
Just pushed some new changes to expain.depesz.com and it's underlying parsing library.
The changes are:
Some stats, for curious ones:
On 6th of April 2020, Amit Kapila committed patch:
Add the option to report WAL usage in EXPLAIN and auto_explain. This commit adds a new option WAL similar to existing option BUFFERS in the EXPLAIN command. This option allows to include information on WAL record generation added by commit df3b181499 in EXPLAIN output. This also allows the WAL usage information to be displayed via the auto_explain module. A new parameter auto_explain.log_wal controls whether WAL usage statistics are printed when an execution plan is logged. This parameter has no effect unless auto_explain.log_analyze is enabled. Author: Julien Rouhaud Reviewed-by: Dilip Kumar and Amit Kapila Discussion: https://postgr.es/m/CAB-hujrP8ZfUkvL5OYETipQwA=e3n7oqHFU=4ZLxWS_Cza3kQQ@mail.gmail.com
Ever since I released explain.depesz.com over 11 years ago there have been cases were people would upload a plan and it didn't parse.
There were many reasons, but the most common was – plan was line-wrapped by injecting new-line characters where there shouldn't be one.
Continue reading Initial support for fixing of line-wrapped plans
For very long time plans with parallel execution showed bogus values. Not any more.
Continue reading Finally – fixed time calculations for parallel plans in explain.depesz.com
Recently got two bug reports:
Additionally, I was kinda upset because plans that include trigger calls did not display properly.
All of this has been fixed today:
On 3rd of April 2019, Tomas Vondra committed patch:
Add SETTINGS option to EXPLAIN, to print modified settings. Query planning is affected by a number of configuration options, and it may be crucial to know which of those options were set to non-default values. With this patch you can say EXPLAIN (SETTINGS ON) to include that information in the query plan. Only options affecting planning, with values different from the built-in default are printed. This patch also adds auto_explain.log_settings option, providing the same capability in auto_explain module. Author: Tomas Vondra Discussion: https://postgr.es/m/e1791b4c-df9c-be02-edc5-7c8874944be0@2ndquadrant.com
On Friday, Zr40 reported on irc that explain.depesz.com doesn't show table/index names for Parallel Seq Scan nodes.
Checked it and found couple of other omissions of the same kind with other Parallel* scans.
Fixed (I hope) all of them in:
The change is not really big, but just figured I'll let you know.