Improve docs for EXPLAIN (IO)

Commit 681daed931 introduced a new EXPLAIN option "IO", but the docs
did not explain what information was added to the output. Expand the
description a little bit, similarly to the other EXPLAIN options.

While at it, fix a typo in the first sentence.

Author: Tomas Vondra <tomas@vondra.me>
This commit is contained in:
Tomas Vondra 2026-06-26 17:57:26 +02:00
parent cdae794af3
commit ed9ec3abb6

View file

@ -303,7 +303,14 @@ ROLLBACK;
<term><literal>IO</literal></term>
<listitem>
<para>
Include information on I/O performed by scan nodes proving such information.
Include information on I/O performed by scan nodes providing such
information.
Specifically, include information about the prefetch queue (the average
and the maximum distance, and the queue capacity), and information about
issued I/O requests (the total number of requests, the average request
size, the number of I/O waits, and the average number of concurrent I/O
requests). The request size is reported in blocks.
In text format, only non-zero values are printed.
This parameter may only be used when <literal>ANALYZE</literal> is also
enabled. It defaults to <literal>FALSE</literal>.
</para>