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[162.195.168.172]) by smtp.gmail.com with ESMTPSA id 8926c6da1cb9f-4ea1de6d4f2sm3450493173.39.2025.01.14.09.45.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 14 Jan 2025 09:45:44 -0800 (PST) Date: Tue, 14 Jan 2025 11:45:42 -0600 From: Nathan Bossart To: Sami Imseih Cc: =?iso-8859-1?Q?Fr=E9d=E9ric?= Yhuel , Robert Treat , wenhui qiu , Robert Haas , "Imseih (AWS), Sami" , David Rowley , Joe Conway , Michael Banck , Laurenz Albe , Melanie Plageman , PostgreSQL Hackers Subject: Re: New GUC autovacuum_max_threshold ? Message-ID: References: <93f3dab5-caa4-4213-9be0-855d5aaa19bf@dalibo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk On Tue, Jan 14, 2025 at 11:08:36AM -0600, Sami Imseih wrote: > After staring at the documentation for a while, I am now > wondering whether we are adequately describing the > rationale for this GUC. The GUC documentation mentions that this is a > 'cap on the value calculated with autovacuum_vacuum_threshold > and autovacuum_vacuum_scale_factor,' which is acceptable; > however, I think further elaboration is necessary in > routine-vacuuming.html#AUTOVACUUM. This is because > scale_factor and threshold are already well-known > and widely understood parameters, and introducing > a third one to the mix deserves a bit more of an > explanation. What do you think? I think it would be odd to explain the intent for one autovacuum parameter while leaving the others unexplained. IMHO it would be better to address this for all such parameters in a follow-up patch. -- nathan