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Wed, 20 Aug 2025 04:42:48 -0700 (PDT) MIME-Version: 1.0 References: <8B89FABB-E020-4EF0-9019-08B1B9E22208@gmail.com> In-Reply-To: <8B89FABB-E020-4EF0-9019-08B1B9E22208@gmail.com> From: Pawel Veselov Date: Wed, 20 Aug 2025 13:42:32 +0200 X-Gm-Features: Ac12FXzLvdhrxLSufOrI6Xg98esy-VS9qdm-GmoJCt1jrz6cIH8EFOKlnnRPot4 Message-ID: Subject: Re: Streaming replica hangs periodically for ~ 1 second - how to diagnose/debug To: Alban Hertroys Cc: Scot Kreienkamp , Adrian Klaver , "depesz@depesz.com" , PostgreSQL General Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: base64 List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk PiA+IOWMgOekgOa4gOaMgOaggOeIgOa8gOa4gOa8gOeUgOeMgOKAgOaMgOa8gOa0gOa0gOakgOeQ gOO8gOKAgOKAgOS8gOeIgOKAgOaEgOeMgOekgOa4gOaMgOaggOeIgOa8gOa4gOa8gOeUgOeMgOO8 gOC0gOCogOC0gOCogOC0gOCogOWMgOaMgOa8gOeQgOKAgOSsgOeIgOaUgOakgOaUgOa4gOasgOaE gOa0gOeAgOKAgOewgOKAgOSEgOeAgOeAgOawgOakgOaMgOaEgOeQgOakgOa8gOa4gOeMgOKAgOSk gOa4gOaYgOeIgOaEgOeMgOeQgOeIgOeUgOaMgOeQgOeUgOeIgOaUgOKAgOSEgOeIgOaMgOaggOak gOeQgOaUgOaMgOeQgOKAgOewgOKAgOSwgOaEgOK0gOWogOK0gOSIgOa8gOekgOKAgOSMgOa8gOeI gOeAgOa8gOeIgOaEgOeQgOaUgOC0gOCogOKggOOcgOOMgOOQgOKkgOKAgOOMgOOggOOQgOK0gOOY gOOQgOOAgOOMgOKAgOewgOKAgOOEgOK0gOOcgOOMgOOQgOK0gOOkgOOEgOOUgOK0gOOEgOOQgOOQ gOOQgOKAgOewgOKAgOWMgOaMgOa8gOeQgOK4gOSsgA0KPiBUaGlzIGxvb2tzIGxpa2UgYSBidWcg aW4gT3V0bG9vayAoYXQgd29yaykgdGhhdCBJIHJhbiBpbnRvIG92ZXIgMyB5ZWFycyBhZ28gYWZ0 ZXIgZW5hYmxpbmcgYmV0YS1zdXBwb3J0IGZvciBVVEYtOCBlbmNvZGluZ+KApiBUaGUgZnVuIHBh cnQgd2FzIHRoYXQgdGhlIG1lc3NhZ2VzIGxvb2tlZCBwZXJmZWN0bHkgZmluZSBvbiBteSBlbmQs IGJ1dCB3ZXJlIGdpYmJlcmlzaCBvbiB0aGUgcmVjZWl2aW5nIGVuZHMgb25seS4gSXMgdGhhdCBi dWcgc3RpbGwgcHJlc2VudCBwZXJoYXBzPw0KDQpJbnRlcmVzdGluZy4NCllvdXIgZW1haWwgY2xp ZW50IHByb2JhYmx5IGluY29ycmVjdGx5IGludGVycHJldHMgVVRGLTE2IGVuY29kaW5nLg0KVGhh dCdzIHdoYXQgdGhlIGNvbnRlbnQgY2hhcnNldCBpcyBpbiBTY290dCdzIGVtYWlsLg0KVGhlIGZp cnN0IHRleHQgY2hhcmFjdGVyIGluIFNjb3R0J3MgZW1haWwgaXMgIlMiIChVMDA1MyksIGJ1dCB3 aGVuDQpzZW5kaW5nKD8pIGl0IHRyYW5zbGF0ZXMgdG8g5YyAIChVNTMwMCkuDQoNCkdtYWlsIHdl YiBhbHNvIGlzIHN0cnVnZ2xpbmcgd2l0aCBpdCwganVkZ2luZyBieSB0aGUgc3BhY2VzIEkgc2Vl DQpiZXR3ZWVuIHRoZSBjaGFyYWN0ZXJzIGluIHRoZSBTY290dCdzIG9yaWdpbmFsLiBUaG9zZSBz cGFjZXMgYXJlDQpyZXBsYWNlZCAnMHgwMCcgY2hhcnMgZnJvbSB0aGUgZmlyc3QgYnl0ZSBvZiBl YWNoIFVURi0xNiBjaGFyLg0KDQo+DQo+IE9yIGlzIGl0IGp1c3QgbXkgZW5kIHRoYXQgdHVybnMg U2NvdHQncyAoYW5kIG9ubHkgU2NvdHQncykgbWVzc2FnZXMgaW50byBnaWJiZXJpc2ggQ2hpbmVz ZT8NCj4NCj4gQWxiYW4gSGVydHJveXMNCj4gLS0NCj4gVGhlcmUgaXMgYWx3YXlzIGFuIGV4Y2Vw dGlvbiB0byBhbHdheXMuDQo+DQo+DQo+DQo+DQo+DQo+DQoNCg0KLS0gDQpXaXRoIGJlc3Qgb2Yg YmVzdCByZWdhcmRzDQpQYXdlbCBTLiBWZXNlbG92DQo=