diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/maintenance.sgml | 72 | ||||
| -rw-r--r-- | doc/src/sgml/runtime.sgml | 82 |
2 files changed, 124 insertions, 30 deletions
diff --git a/doc/src/sgml/maintenance.sgml b/doc/src/sgml/maintenance.sgml index 91ead3dc168..7d1dafad318 100644 --- a/doc/src/sgml/maintenance.sgml +++ b/doc/src/sgml/maintenance.sgml @@ -1,5 +1,5 @@ <!-- -$PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.36 2004/07/24 19:51:22 tgl Exp $ +$PostgreSQL: pgsql/doc/src/sgml/maintenance.sgml,v 1.37 2004/08/05 23:32:10 tgl Exp $ --> <chapter id="maintenance"> @@ -445,22 +445,52 @@ VACUUM </para> <para> - If you simply direct the <systemitem>stderr</> of the <command>postmaster</command> into a - file, the only way to truncate the log file is to stop and restart + If you simply direct the <systemitem>stderr</> of the + <command>postmaster</command> into a + file, you will have log output, but + the only way to truncate the log file is to stop and restart the <command>postmaster</command>. This may be OK if you are using <productname>PostgreSQL</productname> in a development environment, but few production servers would find this behavior acceptable. </para> <para> - The simplest production-grade approach to managing log output is to + A better approach is to send the <command>postmaster</>'s + <systemitem>stderr</> output to some type of log rotation program. + There is a built-in log rotation program, which you can use by + setting the configuration parameter <literal>redirect_stderr</> to + <literal>true</> in <filename>postgresql.conf</>. The control + parameters for this program are described in <xref + linkend="runtime-config-logging-where">. + </para> + + <para> + Alternatively, you might prefer to use an external log rotation + program, if you have one that you are already using with other + server software. For example, the <application>rotatelogs</application> + tool included in the <productname>Apache</productname> distribution + can be used with <productname>PostgreSQL</productname>. To do this, + just pipe the <command>postmaster</>'s + <systemitem>stderr</> output to the desired program. + If you start the server with + <command>pg_ctl</>, then <systemitem>stderr</> + is already redirected to <systemitem>stdout</>, so you just need a + pipe command: + +<programlisting> +pg_ctl start | rotatelogs /var/log/pgsql_log 86400 +</programlisting> + </para> + + <para> + Another production-grade approach to managing log output is to send it all to <application>syslog</> and let <application>syslog</> deal with file rotation. To do this, set the - configuration parameter <literal>log_destination</> to 'syslog' (to log to - <application>syslog</> only) in <filename>postgresql.conf</>. Then - you can send a <literal>SIGHUP</literal> signal to the - <application>syslog</> daemon whenever you want to force it to - start writing a new log file. If you want to automate log + configuration parameter <literal>log_destination</> to <literal>syslog</> + (to log to <application>syslog</> only) in + <filename>postgresql.conf</>. Then you can send a <literal>SIGHUP</literal> + signal to the <application>syslog</> daemon whenever you want to force it + to start writing a new log file. If you want to automate log rotation, the <application>logrotate</application> program can be configured to work with log files from <application>syslog</application>. @@ -471,27 +501,15 @@ VACUUM particularly with large log messages; it may truncate or drop messages just when you need them the most. Also, on <productname>linux</>, <application>syslog</> will sync each message to disk, yielding poor - performance. Use a <literal>-</> at the start of the file name - in the <application>syslog</> config file to disable this behavior. + performance. (You can use a <literal>-</> at the start of the file name + in the <application>syslog</> config file to disable this behavior.) </para> <para> - You may find it more useful to pipe the - <systemitem>stderr</> of the <command>postmaster</> to some type of - log rotation program. If you start the server with - <command>pg_ctl</>, then the <systemitem>stderr</> of the <command>postmaster</command> - is already redirected to <systemitem>stdout</>, so you just need a - pipe command: - -<programlisting> -pg_ctl start | rotatelogs /var/log/pgsql_log 86400 -</programlisting> - - The <productname>PostgreSQL</> distribution doesn't include a - suitable log rotation program, but there are many available on the - Internet. For example, the <application>rotatelogs</application> - tool included in the <productname>Apache</productname> distribution - can be used with <productname>PostgreSQL</productname>. + Note that all the solutions described above take care of starting new + log files at configurable intervals, but they do not handle deletion + of old, no-longer-interesting log files. You will also want to set + up a batch job to periodically delete old log files. </para> </sect1> </chapter> diff --git a/doc/src/sgml/runtime.sgml b/doc/src/sgml/runtime.sgml index 95a8c23c822..9f569712b08 100644 --- a/doc/src/sgml/runtime.sgml +++ b/doc/src/sgml/runtime.sgml @@ -1,5 +1,5 @@ <!-- -$PostgreSQL: pgsql/doc/src/sgml/runtime.sgml,v 1.271 2004/08/03 23:42:59 tgl Exp $ +$PostgreSQL: pgsql/doc/src/sgml/runtime.sgml,v 1.272 2004/08/05 23:32:10 tgl Exp $ --> <Chapter Id="runtime"> @@ -1800,15 +1800,91 @@ SET ENABLE_SEQSCAN TO OFF; option to a list of desired log destinations separated by commas. The default is to log to <systemitem>stderr</systemitem> only. + This option can only be set at server start or in the + <filename>postgresql.conf</filename> configuration file. </para> </listitem> </varlistentry> + <varlistentry id="guc-redirect-stderr" xreflabel="redirect_stderr"> + <term><varname>redirect_stderr</varname> (<type>boolean</type>)</term> + <listitem> + <para> + This option allows messages sent to <application>stderr</> to be + captured and redirected into log files. + This option, in combination with logging to <application>stderr</>, + is often more useful than + logging to <application>syslog</>, since some types of messages + may not appear in <application>syslog</> output (a common example + is dynamic-linker failure messages). + This option can only be set at server start. + </para> + </listitem> + </varlistentry> + + <varlistentry id="guc-log-directory" xreflabel="log_directory"> + <term><varname>log_directory</varname> (<type>string</type>)</term> + <listitem> + <para> + When <varname>redirect_stderr</> is enabled, this option + determines the directory in which log files will be created. + It may be specified as an absolute path, or relative to the + cluster data directory. + This option can only be set at server start or in the + <filename>postgresql.conf</filename> configuration file. + </para> + </listitem> + </varlistentry> + + <varlistentry id="guc-log-filename-prefix" xreflabel="log_filename_prefix"> + <term><varname>log_filename_prefix</varname> (<type>string</type>)</term> + <listitem> + <para> + When <varname>redirect_stderr</> is enabled, this option + sets the prefix of the file names of the created log files. + The postmaster PID and the current time are appended to this + prefix to form an exact log file name. + This option can only be set at server start or in the + <filename>postgresql.conf</filename> configuration file. + </para> + </listitem> + </varlistentry> + + <varlistentry id="guc-log-rotation-age" xreflabel="log_rotation_age"> + <term><varname>log_rotation_age</varname> (<type>integer</type>)</term> + <listitem> + <para> + When <varname>redirect_stderr</> is enabled, this option + determines the maximum lifetime of an individual log file. + After this many minutes have elapsed, a new log file will + be created. Set to zero to disable time-based creation of + new log files. + This option can only be set at server start or in the + <filename>postgresql.conf</filename> configuration file. + </para> + </listitem> + </varlistentry> + + <varlistentry id="guc-log-rotation-size" xreflabel="log_rotation_size"> + <term><varname>log_rotation_size</varname> (<type>integer</type>)</term> + <listitem> + <para> + When <varname>redirect_stderr</> is enabled, this option + determines the maximum size of an individual log file. + After this many kilobytes have been emitted into a log file, + a new log file will be created. Set to zero to disable size-based + creation of new log files. + This option can only be set at server start or in the + <filename>postgresql.conf</filename> configuration file. + </para> + </listitem> + </varlistentry> + <varlistentry id="guc-syslog-facility" xreflabel="syslog_facility"> <term><varname>syslog_facility</varname> (<type>string</type>)</term> <listitem> <para> - If logging to <application>syslog</> is enabled, this option + When logging to <application>syslog</> is enabled, this option determines the <application>syslog</application> <quote>facility</quote> to be used. You may choose from <literal>LOCAL0</>, <literal>LOCAL1</>, @@ -1826,7 +1902,7 @@ SET ENABLE_SEQSCAN TO OFF; <term><varname>syslog_ident</varname> (<type>string</type>)</term> <listitem> <para> - If logging to <application>syslog</> is enabled, this option + When logging to <application>syslog</> is enabled, this option determines the program name used to identify <productname>PostgreSQL</productname> messages in <application>syslog</application> logs. The default is |