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Thu, 15 Nov 2018 05:10:17 +0000 (GMT) Received: from epsmgms1p2new.samsung.com (unknown [182.195.42.42]) by epsmtrp1.samsung.com (KnoxPortal) with ESMTP id 20181115051016epsmtrp147cbf2d93c08154b08ebea4d1b2873be~nNAp3JH9E1674416744epsmtrp1k; Thu, 15 Nov 2018 05:10:16 +0000 (GMT) X-AuditID: b6c32a25-a69ff70000000f0c-fd-5becffb9b33a Received: from epsmtip2.samsung.com ( [182.195.34.31]) by epsmgms1p2new.samsung.com (Symantec Messaging Gateway) with SMTP id B1.2D.03606.8BFFCEB5; Thu, 15 Nov 2018 14:10:16 +0900 (KST) Received: from lmkPC (ip-70-2-253-71.ftwttx.spcsdns.net [70.2.253.71]) by epsmtip2.samsung.com (KnoxPortal) with ESMTPA id 20181115051016epsmtip2b24469e79d48bacfdd4ee61a7deea31c~nNAprCTUb1011510115epsmtip2-; Thu, 15 Nov 2018 05:10:16 +0000 (GMT) From: "myungkyu.lim" To: "'Surafel Temesgen'" Cc: "'PostgreSQL Hackers'" In-Reply-To: Subject: RE: [Todo item] Add entry creation timestamp column to pg_stat_replication Date: Thu, 15 Nov 2018 14:10:21 +0900 Message-ID: <003001d47ca1$8282dc20$87889460$@samsung.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Mailer: Microsoft Outlook 14.0 Content-Language: ko Thread-Index: AQJGM0N8HOY1QBp8pnN6i6q2RmgvzAH04GnbAnEE6D+kSaaDYA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrPIsWRmVeSWpSXmKPExsWy7bCmku7O/2+iDe4eVra4u6+N2WJG2yY2 ByaPnbPusntc2DeNPYApissmJTUnsyy1SN8ugSvj98929oL1PBXnFz5maWA8ztHFyMkhIWAi sejXRvYuRi4OIYGljBKr55xnhXA+MUr0nnjPBlIlJPCNUaJzTgJMR++LzUwQRXuBinrfsUA4 vxklfrzrZQapYhPQl7i+4wjQKA4OEQEDif5GsHXMApYSey41soPYnAKBEqf332QFsYUFQiV6 1y9jBLFZBFQlthx6xgLSygtUf+B0IEiYV0BQ4uTMJywQY7Qlli18zQxxj4LEjrOvGSHiIhKz O9vA4iICThLHlq8He0ZCYAObxO4Jz1khGlwkfvz5yA5hC0u8Or4FypaSeNnfBmWXS9ztuMsI YVdINHT2QcX1JWYvaAN7i1lAU2L9Ln2IvXwSc7oPMoGEJQR4JTrahCBMNYkH57khGmUkVv7a wgZhe0js3X2QdQKj4iwkj81C8tgsJM/MQti1gJFlFaNYakFxbnpqsUmBqV5xYm5xaV66XnJ+ 7iZGcLLQUt3B2LLQ+xCjAAejEg/vCas30UKsiWXFlbmHGCU4mJVEeBfUAIV4UxIrq1KL8uOL SnNSiw8xSnOwKInzVkjOjRYSSE8sSc1OTS1ILYLJMnFwSjUwstyY27oxVfjGCenNYs+OvXG/ 0tByotVo5RYOqSzGmW3+Qiprc4x6hJZWcwvM0D0dOH9t9ZWidC/TSYejsj68uNiu/ees6/Ib q85KK8yvPumUb8LukH1wVoFc8JIJgZbzXG/Y78l6xcHg0ZhuuCfmx7HgXVl2O+epTXOcffw/ +8GJJyatWeVirsRSnJFoqMVcVJwIAIUJXmQSAwAA X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrOLMWRmVeSWpSXmKPExsWy7bCSvO6O/2+iDZ5vN7a4u6+N2WJG2yY2 ByaPnbPusntc2DeNPYApissmJTUnsyy1SN8ugSuj++AKtoL33BW7Jl5iaWBs5+hi5OSQEDCR 6H2xmamLkYtDSGA3o8Sa+79YIRIyEj33bjB3MXIA2cISM29JQNT8ZJT4+fMiM0gNm4C+xPUd R1hBakQEDCT6G8FmMgtYSuy51MgOUX+BUeLdnSOMIAlOgUCJ0/tvgs0XFgiW2Hm7CSzOIqAq seXQMxaQObxAzQdOB4KEeQUEJU7OfMICMVNbovdhKyOMvWzha2aIMxUkdpx9DRUXkZjd2QYW FxFwkji2fD3rBEbhWUhGzUIyahaSUbOQtC9gZFnFKJlaUJybnltsWGCUl1quV5yYW1yal66X nJ+7iREc/FpaOxhPnIg/xCjAwajEw3vC6k20EGtiWXFl7iFGCQ5mJRHeBTVAId6UxMqq1KL8 +KLSnNTiQ4zSHCxK4rzy+ccihQTSE0tSs1NTC1KLYLJMHJxSDYwztUL/hXmwbZx9PsDn4v4l izeeXT1jR9OdxjqOWYqCU8zk7bZqNXW47DqV9tPDeH5lgePRfsnTVoUd1vfX7n/ryxIbvmWi 7/ENneJMvCXdSoJTPzU5frn1hn921Inp23UdpNWiZ2ZHXD3yUkLypcjlFVcToqqm7WrZ1bIt 6qPfH6Np5Yf1joQpsRRnJBpqMRcVJwIAwHctEnoCAAA= X-CMS-MailID: 20181115051017epcas4p3e950b7ea6fa2b6c058c3741c4906be84 X-Msg-Generator: CA Content-Type: text/plain; charset="utf-8" CMS-TYPE: 104P X-CMS-RootMailID: 20180731085657epcms4p86e41bb64a978775023ef8cb77535ef44 References: <1657809367.407321.1533027417725.JavaMail.jboss@ep2ml404> List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk Hi. Thanks for your feedback. > Can you explain the purpose of this feature more because now we have colu= mns to report replication delay times like write_lag ,flush_lag and replay_= lag that can use for similar purpose . I think, time elapsed stats are very useful on DML query active system,=20 but not present that stats on idle system - not query, or only select. sent_lsn =7C 0/5476C88 write_lsn =7C 0/5476C88 flush_lsn =7C 0/5476C88 replay_lsn =7C 0/5476C88 write_lag =7C 00:00:00.000055 flush_lag =7C 00:00:00.000855 replay_lag =7C 00:00:00.000914 sync_priority =7C 0 sync_state =7C async last_msg_send_time =7C 2018-11-15 14:04:39.65889+09 state =7C streaming sent_lsn =7C 0/5476CC0 write_lsn =7C 0/5476CC0 flush_lsn =7C 0/5476CC0 replay_lsn =7C 0/5476CC0 write_lag =7C flush_lag =7C replay_lag =7C sync_priority =7C 0 sync_state =7C async last_msg_send_time =7C 2018-11-15 14:05:02.935457+09 state =7C streaming sent_lsn =7C 0/5476CC0 write_lsn =7C 0/5476CC0 flush_lsn =7C 0/5476CC0 replay_lsn =7C 0/5476CC0 write_lag =7C flush_lag =7C replay_lag =7C sync_priority =7C 0 sync_state =7C async last_msg_send_time =7C 2018-11-15 14:06:23.128947+09 This timestamp column is useful when react interval check and debugging on = idle system. Best regards, Myungkyu, Lim