From: Sreejith P <sreejith@lifetrenz.com>
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Subject: Delete Query slowdown Slave database.
Message-Id: <A53FF53D-8578-4271-ACCD-8C647FE93F53@lifetrenz.com>
Date: Thu, 28 Nov 2024 23:55:31 +0530
To: pgsql-general@lists.postgresql.org
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Hello,

My doubt here is, in a master - slave (streaming replication) set up, when =
I run a long running delete query for deleting 80 million records, . All qu=
eries in slave started running 2- 5 mins all of a sudden. When I check SQL =
analyse, most of the queries, planner used to choose seq scan, instead of s=
eq scan.=20

What could be the possibility?

How delete query running in Master affect secondary(Slave) DB.

Is it related to shared memory ?


NB: Problem solved after restarting slave servers.=20


Thanks
Sreejith


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<html><head><meta http-equiv=3D"content-type" content=3D"text/html; charset=
=3Dus-ascii"></head><body style=3D"overflow-wrap: break-word; -webkit-nbsp-=
mode: space; line-break: after-white-space;">Hello,<div><br></div><div>My d=
oubt here is, in a master - slave (streaming replication) set up, when I ru=
n a long running delete query for deleting 80 million records, . All querie=
s in <b>slave started running 2- 5 mins all of a sudden. When I check SQL a=
nalyse, most of the queries, planner used to choose seq scan, </b>instead o=
f seq scan.&nbsp;</div><div><b><br></b></div><div>What could be the possibi=
lity?</div><div><br></div><div>How delete query running in Master affect se=
condary(Slave) DB.</div><div><br></div><div>Is it related to shared memory =
?</div><div><br></div><div><br></div><div>NB: Problem solved after restarti=
ng slave servers.&nbsp;</div><div><br></div><div><br></div><div><br></div><=
div>Thanks</div><div>Sreejith</div><div><br></div></body></html>
<br>
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