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+0100 Content-Type: multipart/alternative; boundary="------------ZgX0HXZxBhq0Ct68nb8hPhFn" Message-ID: <290abcbf-8d1c-4f75-bd31-2963331edb40@gmx.de> Date: Tue, 3 Feb 2026 02:02:52 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: pgsql-performance@postgresql.org From: Dirk Krautschick Subject: performance impact on read replicas during heavy vacuums on primary X-Provags-ID: V03:K1:nwLwRWV0+U/7CSpc+SypDExSrc61AC4dblCz5XkldHhYLST65Jj pjrs9szj/8/h7P8floDRwbCWSHC/gCwrO6YIA0t95lCQ3XbMfDhskAU8n+eAP5pZ9+mVDS4 qLxzkDe4/5PpHd8xBrkf1rMdHx/1S28ujQSgWnqbmPrytqejcye2WWohewwEXat3JDxmNFn aNBisw7w4L7CStzDcE+2g== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:2PC9//rQD2E=;1WjDk8EqRuXxM5s8Z9Zptzragb1 oV1XF9e9rVWcF1TIiRiDE9Tn5dYIxg0UUU6nUN4oPxz0909WPsrypzpztgvxW7CvAiaAFofOV iphmKTNSEyKc7UGP4ZzupZjKeqpr7CxozndgUqdnrlP8Erkw0oC2NKgPAblhyMgau5HF3MVRH mkxy/JwvsIi8ybH1cnO99V2yt5rz38LE585LfcuaefLN7ldm5dR+T9kWgeRKzaRLl4+G0QVhb 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I do not get this reproduced ...only the lag is clear but even=20 hammering down the primary with vaccum keeps my standby answering fine. Cheers --------------ZgX0HXZxBhq0Ct68nb8hPhFn Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Is there a scenario, where a very heavy vacuum on the primary side is affecting significantly=C2=A0
the read replica(s) in matter of performance (not the overall apply lag, which is expected) of=C2=A0
selects? I do not get this reproduced ...only the lag is clear but even hammering down the=C2=A0
primary with vaccum keeps my standby answering fine.

Cheers

--------------ZgX0HXZxBhq0Ct68nb8hPhFn--