Date: Wed, 9 Mar 2022 16:52:37 -0800
From: Nathan Bossart <nathandbossart@gmail.com>
To: "Imseih (AWS), Sami" <simseih@amazon.com>
Cc: Masahiko Sawada <sawada.mshk@gmail.com>, Peter Geoghegan <pg@bowt.ie>,
	"Bossart, Nathan" <bossartn@amazon.com>,
	Justin Pryzby <pryzby@telsasoft.com>,
	"pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: Add index scan progress to pg_stat_progress_vacuum
Message-ID: <20220310005237.GA307769@nathanxps13>
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Precedence: bulk

I took a look at the latest patch set.

+      <entry role="catalog_table_entry"><para role="column_definition">
+       <structfield>indexes_total</structfield> <type>bigint</type>
+      </para>
+      <para>
+       The number of indexes to be processed in the 
+       <literal>vacuuming indexes</literal> 
+       or <literal>cleaning up indexes</literal> phase. It is set to
+       <literal>0</literal> when vacuum is not in any of these phases.
+      </para></entry>

Could we avoid resetting it to 0 unless INDEX_CLEANUP was turned off or
failsafe kicked in?  It might be nice to know how many indexes the vacuum
intends to process.  I don't feel too strongly about this, so if it would
add a lot of complexity, it might be okay as is.

 	BTreeShmemInit();
 	SyncScanShmemInit();
 	AsyncShmemInit();
+	vacuum_worker_init();

Don't we also need to add the size of the hash table to
CalculateShmemSize()?

+ * A command type can optionally define a callback function
+ * which will derive Datum values rather than use values
+ * directly from the backends progress array.

I think this can be removed.

-- 
Nathan Bossart
Amazon Web Services: https://aws.amazon.com