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Wed, 28 Jan 2026 07:55:26 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kurilemu.de; s=schmee; t=1769604872; bh=VVNIOJ83y8QAHasq7zxQ5B3GbSCSLcDea/j0aPCVGvg=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=Xc3E4R3Y1FD8544EDXVX/G+J1FMkuUXp6/JljcSeES9S1e2318LAzDZtR9SyX/UWU do5RS+Yz7Z2G/MqYw+ekDAd8vwQNbrVWdzmpL9IEBT630jzXi1lAad8Gwfo/AFQxjl ufW1J86Pj4BruWJ7WpUSmtK0POR3Qkj6cI3Py14FtmcUXgenHYPPalsuTHzRYx4Pk9 NC07S/JnHU7Hx9//y6CTHo6c5r6v8dNmXlOPbyuCz61qC7H4aEQKHIKLeSI/oFkaQS Sp37sSTVnlFoEE/+n4W+Y7Dnzr6dt9UjqJc8aoL9ofgKBze1iHjzsVKK8UkujPRr0e gangmCYXevQPQ== Received: by schmee.kurilemu.internal (Postfix, from userid 1000) id AA5737A; Wed, 28 Jan 2026 13:54:32 +0100 (CET) Date: Wed, 28 Jan 2026 13:54:32 +0100 From: =?utf-8?Q?=C3=81lvaro?= Herrera To: Ahmed Et-tanany Cc: pgsql-hackers@lists.postgresql.org Subject: Re: [PATCH] Add max_logical_replication_slots GUC Message-ID: <202601281248.qjv5oru7hxlz@alvherre.pgsql> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk On 2026-Jan-28, Ahmed Et-tanany wrote: > In practice, a burst of logical replication activity can exhaust all > available replication slots, which in turn prevents physical standbys > from connecting or restarting. > > This is problematic because logical replication slots are often > user-managed and can grow dynamically, Ah, you mean that users doing CREATE SUBSCRIPTION could cause the limit to be reached, possibly blocking streaming replication. Yeah, it makes sense to have a separate limit. -- Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/ "[PostgreSQL] is a great group; in my opinion it is THE best open source development communities in existence anywhere." (Lamar Owen)