|
- <?xml version="1.0" encoding="UTF-8" standalone="no"?>
- <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>27.1. Standard Unix Tools</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets V1.79.1" /><link rel="prev" href="monitoring.html" title="Chapter 27. Monitoring Database Activity" /><link rel="next" href="monitoring-stats.html" title="27.2. The Statistics Collector" /></head><body><div xmlns="http://www.w3.org/TR/xhtml1/transitional" class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">27.1. Standard Unix Tools</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="monitoring.html" title="Chapter 27. Monitoring Database Activity">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="monitoring.html" title="Chapter 27. Monitoring Database Activity">Up</a></td><th width="60%" align="center">Chapter 27. Monitoring Database Activity</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 12.4 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="monitoring-stats.html" title="27.2. The Statistics Collector">Next</a></td></tr></table><hr></hr></div><div class="sect1" id="MONITORING-PS"><div class="titlepage"><div><div><h2 class="title" style="clear: both">27.1. Standard Unix Tools</h2></div></div></div><a id="id-1.6.14.6.2" class="indexterm"></a><p>
- On most Unix platforms, <span class="productname">PostgreSQL</span> modifies its
- command title as reported by <code class="command">ps</code>, so that individual server
- processes can readily be identified. A sample display is
-
- </p><pre class="screen">
- $ ps auxww | grep ^postgres
- postgres 15551 0.0 0.1 57536 7132 pts/0 S 18:02 0:00 postgres -i
- postgres 15554 0.0 0.0 57536 1184 ? Ss 18:02 0:00 postgres: background writer
- postgres 15555 0.0 0.0 57536 916 ? Ss 18:02 0:00 postgres: checkpointer
- postgres 15556 0.0 0.0 57536 916 ? Ss 18:02 0:00 postgres: walwriter
- postgres 15557 0.0 0.0 58504 2244 ? Ss 18:02 0:00 postgres: autovacuum launcher
- postgres 15558 0.0 0.0 17512 1068 ? Ss 18:02 0:00 postgres: stats collector
- postgres 15582 0.0 0.0 58772 3080 ? Ss 18:04 0:00 postgres: joe runbug 127.0.0.1 idle
- postgres 15606 0.0 0.0 58772 3052 ? Ss 18:07 0:00 postgres: tgl regression [local] SELECT waiting
- postgres 15610 0.0 0.0 58772 3056 ? Ss 18:07 0:00 postgres: tgl regression [local] idle in transaction
- </pre><p>
-
- (The appropriate invocation of <code class="command">ps</code> varies across different
- platforms, as do the details of what is shown. This example is from a
- recent Linux system.) The first process listed here is the
- master server process. The command arguments
- shown for it are the same ones used when it was launched. The next five
- processes are background worker processes automatically launched by the
- master process. (The <span class="quote">“<span class="quote">stats collector</span>”</span> process will not be present
- if you have set the system not to start the statistics collector; likewise
- the <span class="quote">“<span class="quote">autovacuum launcher</span>”</span> process can be disabled.)
- Each of the remaining
- processes is a server process handling one client connection. Each such
- process sets its command line display in the form
-
- </p><pre class="screen">
- postgres: <em class="replaceable"><code>user</code></em> <em class="replaceable"><code>database</code></em> <em class="replaceable"><code>host</code></em> <em class="replaceable"><code>activity</code></em>
- </pre><p>
-
- The user, database, and (client) host items remain the same for
- the life of the client connection, but the activity indicator changes.
- The activity can be <code class="literal">idle</code> (i.e., waiting for a client command),
- <code class="literal">idle in transaction</code> (waiting for client inside a <code class="command">BEGIN</code> block),
- or a command type name such as <code class="literal">SELECT</code>. Also,
- <code class="literal">waiting</code> is appended if the server process is presently waiting
- on a lock held by another session. In the above example we can infer
- that process 15606 is waiting for process 15610 to complete its transaction
- and thereby release some lock. (Process 15610 must be the blocker, because
- there is no other active session. In more complicated cases it would be
- necessary to look into the
- <a class="link" href="view-pg-locks.html" title="51.74. pg_locks"><code class="structname">pg_locks</code></a>
- system view to determine who is blocking whom.)
- </p><p>
- If <a class="xref" href="runtime-config-logging.html#GUC-CLUSTER-NAME">cluster_name</a> has been configured the
- cluster name will also be shown in <code class="command">ps</code> output:
- </p><pre class="screen">
- $ psql -c 'SHOW cluster_name'
- cluster_name
- --------------
- server1
- (1 row)
-
- $ ps aux|grep server1
- postgres 27093 0.0 0.0 30096 2752 ? Ss 11:34 0:00 postgres: server1: background writer
- ...
- </pre><p>
- </p><p>
- If you have turned off <a class="xref" href="runtime-config-logging.html#GUC-UPDATE-PROCESS-TITLE">update_process_title</a> then the
- activity indicator is not updated; the process title is set only once
- when a new process is launched. On some platforms this saves a measurable
- amount of per-command overhead; on others it's insignificant.
- </p><div class="tip"><h3 class="title">Tip</h3><p>
- <span class="productname">Solaris</span> requires special handling. You must
- use <code class="command">/usr/ucb/ps</code>, rather than
- <code class="command">/bin/ps</code>. You also must use two <code class="option">w</code>
- flags, not just one. In addition, your original invocation of the
- <code class="command">postgres</code> command must have a shorter
- <code class="command">ps</code> status display than that provided by each
- server process. If you fail to do all three things, the <code class="command">ps</code>
- output for each server process will be the original <code class="command">postgres</code>
- command line.
- </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="monitoring.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="monitoring.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="monitoring-stats.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 27. Monitoring Database Activity </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 27.2. The Statistics Collector</td></tr></table></div></body></html>
|
