Message-ID: <0ce31eb2-4209-dc00-adf9-4d2c05ec5187@jakobs.com>
Date: Tue, 2 Apr 2024 19:42:11 +0200
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To: Rajesh Kumar <rajeshkumar.dba09@gmail.com>
Cc: Pgsql-admin <pgsql-admin@lists.postgresql.org>
References: 
 <CAJk5Atb6CnsgAJUQ--UPgvRH-eZUhhL__P9-pz=XZsq=r29ShA@mail.gmail.com>
 <58661f82-620c-8116-efe7-23266578289c@jakobs.com>
 <CAJk5AtbDMDD5HKP796qoNPzKqE4qWgnr-ySE7ErED6ph6ebdtw@mail.gmail.com>
From: Holger Jakobs <holger@jakobs.com>
Subject: Re: Deadlock
In-Reply-To: 
 <CAJk5AtbDMDD5HKP796qoNPzKqE4qWgnr-ySE7ErED6ph6ebdtw@mail.gmail.com>
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From: Holger Jakobs <holger@jakobs.com>
To: Rajesh Kumar <rajeshkumar.dba09@gmail.com>
Cc: Pgsql-admin <pgsql-admin@lists.postgresql.org>
Message-ID: <0ce31eb2-4209-dc00-adf9-4d2c05ec5187@jakobs.com>
Subject: Re: Deadlock
References: <CAJk5Atb6CnsgAJUQ--UPgvRH-eZUhhL__P9-pz=XZsq=r29ShA@mail.gmail.com>
 <58661f82-620c-8116-efe7-23266578289c@jakobs.com>
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    <p><br>
    </p>
    <div class=3D"moz-cite-prefix">Am 02.04.24 um 19:09 schrieb Rajesh
      Kumar:<br>
    </div>
    <blockquote type=3D"cite"
cite=3D"mid:CAJk5AtbDMDD5HKP796qoNPzKqE4qWgnr-ySE7ErED6ph6ebdtw@mail.gmai=
l.com">
      <meta http-equiv=3D"content-type" content=3D"text/html; charset=3DU=
TF-8">
      <div dir=3D"auto">Yes, I am trying to find out what message i shoul=
d
        reply if I receive email with deadlock notification.
        <div dir=3D"auto"><br>
        </div>
        <div dir=3D"auto">I understand how deadlock occurs, hot to find
          them in logs, prevention of deadlock(ex: oqueries in order)
          etc.</div>
        <div dir=3D"auto"><br>
        </div>
        <div dir=3D"auto">But since the deadlock_timeout is 1s, they don'=
t
          probably hang around. So post getting an alert, not sure what
          to respond to them</div>
      </div>
      <br>
      <div class=3D"gmail_quote">
        <div dir=3D"ltr" class=3D"gmail_attr">On Tue, 2 Apr 2024, 22:15
          Holger Jakobs, &lt;<a href=3D"mailto:holger@jakobs.com"
            moz-do-not-send=3D"true" class=3D"moz-txt-link-freetext">holg=
er@jakobs.com</a>&gt;
          wrote:<br>
        </div>
        <blockquote class=3D"gmail_quote" style=3D"margin:0 0 0
          .8ex;border-left:1px #ccc solid;padding-left:1ex">
          <div>
            <div>Am 02.04.24 um 18:40 schrieb Rajesh Kumar:<br>
            </div>
            <blockquote type=3D"cite">
              <div dir=3D"auto">Hi
                <div dir=3D"auto"><br>
                </div>
                <div dir=3D"auto">If I receive an alert for deadlock, wha=
t
                  should I do? Like what analysis should I do? No way to
                  find a root cause?</div>
                <div dir=3D"auto">Under pg_locks, what I can analyse?=C2=A0=
</div>
                <div dir=3D"auto"><br>
                </div>
              </div>
            </blockquote>
            <p>If you receive an error with a deadlock, the current
              transaction is dead. You have to decide whether to try
              again.</p>
            <p>Within the error message you find a hint which other (not
              aborted) transaction was involved in the deadlock. So you
              have all the information you need to find the culprit.</p>
            <p>Regards,</p>
            <p>Holger<br>
            </p>
            <div>-- <br>
              <p>Holger Jakobs, Bergisch Gladbach, Tel. +49-178-9759012<b=
r>
                <img src=3D"cid:part1.CLyhcq2Z.UZ3YijWJ@jakobs.com" alt=3D=
""
                  title=3D"chat with me on Signal messenger"
                  moz-do-not-send=3D"true"><br>
                <a
href=3D"https://signal.me/#eu/GpIP259bBne_JiBYJFvbZCLYJELhB-92nJfncACL1LU=
eBOphfXFFgLYYVXv_AGhg"
                  target=3D"_blank" rel=3D"noreferrer"
                  moz-do-not-send=3D"true">chat with me on Signal
                  messenger</a></p>
            </div>
          </div>
        </blockquote>
      </div>
    </blockquote>
    <div class=3D"moz-signature">I wonder what you are writing about. A
      database doesn't send email notifications. That must be a feature
      of some application.</div>
    <div class=3D"moz-signature"><br>
    </div>
    <div class=3D"moz-signature">So you will have to deal the the
      application code or its developers.</div>
    <div class=3D"moz-signature"><br>
    </div>
    <div class=3D"moz-signature">Or is it a customer sending you a messag=
e
      that some deadlock happened on their system? Still, you have to
      deal with the application code or the log files of the database
      system.</div>
    <div class=3D"moz-signature"><br>
    </div>
    <div class=3D"moz-signature">Regards,</div>
    <div class=3D"moz-signature">Holger<br>
    </div>
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