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To: <pgsql-admin@postgresql.org>
From: wenhang.pan <wenhang.pan@qunar.com>
Subject: multiple process of PostgreSQL running on the same port and same
 directory
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Date: Tue, 28 Jul 2015 14:23:59 +0800
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This is the processes I catched:

postgres 5260 0.0 0.0 1224332 37232 ? S Jul13 0:13 \
/opt/pg94/bin/postgres -D /export/pg940_data

postgres 31193 0.0 0.0 1224332 976 ? Ss 00:20 0:00 \
/opt/pg94/bin/postgres -D /export/pg940_data

I found the similar question: ps output shows multiple instances of 
PostgreSQL running on the same port 
<http://www.postgresql.org/message-id/27699.1347932194@sss.pgh.pa.us> , 
but I wanna konw when to fork a postmaster process, and what does it do.

PostgreSQL version:
postgres=# select version();
version
--------------------------------------------------------------------------------------------------------------
  PostgreSQL 9.4.4 on x86_64-unknown-linux-gnu, compiled by gcc (GCC) 
4.4.7 20120313 (Red Hat 4.4.7-3), 64-bit
(1 row)

Thanks.


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<html>
  <head>

    <meta http-equiv="content-type" content="text/html; charset=utf-8">
  </head>
  <body bgcolor="#FFFFFF" text="#000000">
    This is the processes I catched:<br>
    <br>
    <div class="moz-signature">postgres 5260 0.0 0.0 1224332 37232 ? S
      Jul13 0:13 \<br>
      /opt/pg94/bin/postgres -D /export/pg940_data <br>
      <br>
      postgres 31193 0.0 0.0 1224332 976 ? Ss 00:20 0:00 \<br>
      /opt/pg94/bin/postgres -D /export/pg940_data<br>
      <br>
      I found the similar question: <a
href="http://www.postgresql.org/message-id/27699.1347932194@sss.pgh.pa.us">ps
        output shows multiple instances of PostgreSQL running on the
        same port</a> , but I wanna konw when to fork a postmaster
      process, and what does it do.<br>
      <br>
      PostgreSQL version:<br>
      postgres=# select version();<br>
                                                        
      version                                                    <br>
--------------------------------------------------------------------------------------------------------------<br>
       PostgreSQL 9.4.4 on x86_64-unknown-linux-gnu, compiled by gcc
      (GCC) 4.4.7 20120313 (Red Hat 4.4.7-3), 64-bit<br>
      (1 row)<br>
      <br>
      Thanks.<br>
      <br>
    </div>
  </body>
</html>

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