mirror of
https://git.postgresql.org/git/postgresql.git
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Doc: improve documentation of configuration settings that have units.
When we added the GUC units feature, we didn't make any great effort to adjust the documentation of individual GUCs; they tended to still say things like "this is the number of milliseconds that ...", even though users might prefer to write some other units, and SHOW might even show the value in other units. Commit6c9fb69f2
made an effort to improve this situation, but I thought it made things less readable by injecting units information in mid-sentence. It also wasn't very consistent, and did not touch all the GUCs that have units. To improve matters, standardize on the phrasing "If this value is specified without units, it is taken as <units>". Also, try to standardize where this is mentioned, right before the specification of the default. (In a couple of places, doing that would've required more rewriting than seemed justified, so I wasn't 100% consistent about that.) I also tried to use the phrases "amount of time", "amount of memory", etc rather than describing the contents of GUCs in other ways, as those were the majority usage in places that weren't overcommitting to a particular unit. (I left "length of time" alone in a couple of places, though.) I failed to resist the temptation to copy-edit some awkward text, too. Backpatch to v12, like6c9fb69f2
, mainly because v12 hasn't diverged much from HEAD yet. Discussion: https://postgr.es/m/15882.1571942223@sss.pgh.pa.us
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@ -883,9 +883,10 @@ include_dir 'conf.d'
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</term>
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</term>
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<listitem>
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<listitem>
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<para>
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<para>
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Specifies the duration of inactivity after which TCP should
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Specifies the amount of time with no network activity after which
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send a keepalive message to the client (defaults to seconds).
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the operating system should send a TCP keepalive message to the client.
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A value of 0 uses the system default.
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If this value is specified without units, it is taken as seconds.
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A value of 0 (the default) selects the operating system's default.
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This parameter is supported only on systems that support
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This parameter is supported only on systems that support
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<symbol>TCP_KEEPIDLE</symbol> or an equivalent socket option, and on
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<symbol>TCP_KEEPIDLE</symbol> or an equivalent socket option, and on
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Windows; on other systems, it must be zero.
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Windows; on other systems, it must be zero.
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@ -894,7 +895,7 @@ include_dir 'conf.d'
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</para>
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</para>
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<note>
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<note>
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<para>
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<para>
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On Windows, a value of 0 will set this parameter to 2 hours,
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On Windows, setting a value of 0 will set this parameter to 2 hours,
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since Windows does not provide a way to read the system default value.
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since Windows does not provide a way to read the system default value.
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</para>
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</para>
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</note>
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</note>
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@ -909,10 +910,10 @@ include_dir 'conf.d'
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</term>
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</term>
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<listitem>
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<listitem>
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<para>
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<para>
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Specifies the duration after which a TCP keepalive message
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Specifies the amount of time after which a TCP keepalive message
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that is not acknowledged by the client should be retransmitted
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that has not been acknowledged by the client should be retransmitted.
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(defaults to seconds).
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If this value is specified without units, it is taken as seconds.
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A value of 0 uses the system default.
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A value of 0 (the default) selects the operating system's default.
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This parameter is supported only on systems that support
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This parameter is supported only on systems that support
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<symbol>TCP_KEEPINTVL</symbol> or an equivalent socket option, and on
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<symbol>TCP_KEEPINTVL</symbol> or an equivalent socket option, and on
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Windows; on other systems, it must be zero.
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Windows; on other systems, it must be zero.
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@ -921,7 +922,7 @@ include_dir 'conf.d'
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</para>
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</para>
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<note>
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<note>
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<para>
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<para>
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On Windows, a value of 0 will set this parameter to 1 second,
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On Windows, setting a value of 0 will set this parameter to 1 second,
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since Windows does not provide a way to read the system default value.
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since Windows does not provide a way to read the system default value.
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</para>
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</para>
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</note>
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</note>
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@ -936,9 +937,9 @@ include_dir 'conf.d'
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</term>
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</term>
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<listitem>
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<listitem>
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<para>
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<para>
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Specifies the number of TCP keepalives that can be lost before
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Specifies the number of TCP keepalive messages that can be lost before
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the server's connection to the client is considered dead.
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the server's connection to the client is considered dead.
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A value of 0 uses the system default.
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A value of 0 (the default) selects the operating system's default.
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This parameter is supported only on systems that support
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This parameter is supported only on systems that support
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<symbol>TCP_KEEPCNT</symbol> or an equivalent socket option;
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<symbol>TCP_KEEPCNT</symbol> or an equivalent socket option;
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on other systems, it must be zero.
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on other systems, it must be zero.
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@ -961,9 +962,10 @@ include_dir 'conf.d'
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</term>
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</term>
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<listitem>
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<listitem>
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<para>
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<para>
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Specifies duration (defaults to milliseconds) that transmitted data may
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Specifies the amount of time that transmitted data may
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remain unacknowledged before a connection is forcibly closed.
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remain unacknowledged before the TCP connection is forcibly closed.
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A value of 0 uses the system default.
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If this value is specified without units, it is taken as milliseconds.
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A value of 0 (the default) selects the operating system's default.
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This parameter is supported only on systems that support
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This parameter is supported only on systems that support
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<symbol>TCP_USER_TIMEOUT</symbol>; on other systems, it must be zero.
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<symbol>TCP_USER_TIMEOUT</symbol>; on other systems, it must be zero.
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In sessions connected via a Unix-domain socket, this parameter is
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In sessions connected via a Unix-domain socket, this parameter is
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@ -971,8 +973,7 @@ include_dir 'conf.d'
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</para>
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</para>
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<note>
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<note>
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<para>
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<para>
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This parameter is not supported on Windows and on Linux version
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This parameter is not supported on Windows, and must be zero.
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2.6.36 or older.
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</para>
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</para>
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</note>
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</note>
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</listitem>
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</listitem>
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@ -996,10 +997,11 @@ include_dir 'conf.d'
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<listitem>
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<listitem>
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<para>
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<para>
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Maximum duration to complete client authentication (defaults to seconds). If a
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Maximum amount of time allowed to complete client authentication. If a
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would-be client has not completed the authentication protocol in
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would-be client has not completed the authentication protocol in
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this much time, the server closes the connection. This prevents
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this much time, the server closes the connection. This prevents
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hung clients from occupying a connection indefinitely.
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hung clients from occupying a connection indefinitely.
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If this value is specified without units, it is taken as seconds.
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The default is one minute (<literal>1m</literal>).
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The default is one minute (<literal>1m</literal>).
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This parameter can only be set in the <filename>postgresql.conf</filename>
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This parameter can only be set in the <filename>postgresql.conf</filename>
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file or on the server command line.
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file or on the server command line.
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@ -1495,10 +1497,14 @@ include_dir 'conf.d'
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memory buffers. The default is typically 128 megabytes
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memory buffers. The default is typically 128 megabytes
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(<literal>128MB</literal>), but might be less if your kernel settings will
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(<literal>128MB</literal>), but might be less if your kernel settings will
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not support it (as determined during <application>initdb</application>).
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not support it (as determined during <application>initdb</application>).
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This setting must be at least 128 kilobytes. (Non-default
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This setting must be at least 128 kilobytes. However,
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values of <symbol>BLCKSZ</symbol> change the minimum.) However,
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settings significantly higher than the minimum are usually needed
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settings significantly higher than the minimum are usually needed
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for good performance. This parameter can only be set at server start.
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for good performance.
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If this value is specified without units, it is taken as blocks,
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that is <symbol>BLCKSZ</symbol> bytes, typically 8kB.
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(Non-default values of <symbol>BLCKSZ</symbol> change the minimum
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value.)
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This parameter can only be set at server start.
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</para>
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</para>
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<para>
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<para>
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@ -1591,10 +1597,15 @@ include_dir 'conf.d'
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</term>
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</term>
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<listitem>
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<listitem>
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<para>
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<para>
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Sets the maximum number of temporary buffers used by each database
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Sets the maximum amount of memory used for temporary buffers within
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session. These are session-local buffers used only for access to
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each database session. These are session-local buffers used only
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temporary tables. The default is eight megabytes
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for access to temporary tables.
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(<literal>8MB</literal>). The setting can be changed within individual
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If this value is specified without units, it is taken as blocks,
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that is <symbol>BLCKSZ</symbol> bytes, typically 8kB.
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The default is eight megabytes (<literal>8MB</literal>).
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(If <symbol>BLCKSZ</symbol> is not 8kB, the default value scales
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proportionally to it.)
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This setting can be changed within individual
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sessions, but only before the first use of temporary tables
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sessions, but only before the first use of temporary tables
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within the session; subsequent attempts to change the value will
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within the session; subsequent attempts to change the value will
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have no effect on that session.
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have no effect on that session.
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@ -1653,9 +1664,10 @@ include_dir 'conf.d'
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</term>
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</term>
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<listitem>
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<listitem>
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<para>
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<para>
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Specifies the amount of memory to be used by internal sort operations
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Sets the maximum amount of memory to be used by a query operation
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and hash tables before writing to temporary disk files. The value
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(such as a sort or hash table) before writing to temporary disk files.
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defaults to four megabytes (<literal>4MB</literal>).
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If this value is specified without units, it is taken as kilobytes.
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The default value is four megabytes (<literal>4MB</literal>).
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Note that for a complex query, several sort or hash operations might be
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Note that for a complex query, several sort or hash operations might be
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running in parallel; each operation will be allowed to use as much memory
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running in parallel; each operation will be allowed to use as much memory
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as this value specifies before it starts to write data into temporary
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as this value specifies before it starts to write data into temporary
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@ -1681,7 +1693,9 @@ include_dir 'conf.d'
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<para>
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<para>
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Specifies the maximum amount of memory to be used by maintenance
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Specifies the maximum amount of memory to be used by maintenance
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operations, such as <command>VACUUM</command>, <command>CREATE
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operations, such as <command>VACUUM</command>, <command>CREATE
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INDEX</command>, and <command>ALTER TABLE ADD FOREIGN KEY</command>. It defaults
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INDEX</command>, and <command>ALTER TABLE ADD FOREIGN KEY</command>.
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If this value is specified without units, it is taken as kilobytes.
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It defaults
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to 64 megabytes (<literal>64MB</literal>). Since only one of these
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to 64 megabytes (<literal>64MB</literal>). Since only one of these
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operations can be executed at a time by a database session, and
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operations can be executed at a time by a database session, and
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an installation normally doesn't have many of them running
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an installation normally doesn't have many of them running
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@ -1708,7 +1722,9 @@ include_dir 'conf.d'
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<listitem>
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<listitem>
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<para>
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<para>
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Specifies the maximum amount of memory to be used by each
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Specifies the maximum amount of memory to be used by each
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autovacuum worker process. It defaults to -1, indicating that
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autovacuum worker process.
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If this value is specified without units, it is taken as kilobytes.
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It defaults to -1, indicating that
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the value of <xref linkend="guc-maintenance-work-mem"/> should
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the value of <xref linkend="guc-maintenance-work-mem"/> should
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be used instead. The setting has no effect on the behavior of
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be used instead. The setting has no effect on the behavior of
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<command>VACUUM</command> when run in other contexts.
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<command>VACUUM</command> when run in other contexts.
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@ -1730,6 +1746,7 @@ include_dir 'conf.d'
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equivalent), less a safety margin of a megabyte or so. The safety
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equivalent), less a safety margin of a megabyte or so. The safety
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margin is needed because the stack depth is not checked in every
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margin is needed because the stack depth is not checked in every
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routine in the server, but only in key potentially-recursive routines.
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routine in the server, but only in key potentially-recursive routines.
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If this value is specified without units, it is taken as kilobytes.
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The default setting is two megabytes (<literal>2MB</literal>), which
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The default setting is two megabytes (<literal>2MB</literal>), which
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is conservatively small and unlikely to risk crashes. However,
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is conservatively small and unlikely to risk crashes. However,
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it might be too small to allow execution of complex functions.
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it might be too small to allow execution of complex functions.
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@ -1819,8 +1836,8 @@ include_dir 'conf.d'
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for temporary files, such as sort and hash temporary files, or the
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for temporary files, such as sort and hash temporary files, or the
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storage file for a held cursor. A transaction attempting to exceed
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storage file for a held cursor. A transaction attempting to exceed
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this limit will be canceled.
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this limit will be canceled.
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The default unit is kilobytes, and <literal>-1</literal> (the
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If this value is specified without units, it is taken as kilobytes.
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default) means no limit.
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<literal>-1</literal> (the default) means no limit.
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Only superusers can change this setting.
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Only superusers can change this setting.
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</para>
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</para>
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<para>
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<para>
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@ -1907,8 +1924,9 @@ include_dir 'conf.d'
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</term>
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</term>
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<listitem>
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<listitem>
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<para>
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<para>
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The duration (defaults to milliseconds) that the process will sleep
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The amount of time that the process will sleep
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when the cost limit has been exceeded.
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when the cost limit has been exceeded.
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If this value is specified without units, it is taken as milliseconds.
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The default value is zero, which disables the cost-based vacuum
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The default value is zero, which disables the cost-based vacuum
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delay feature. Positive values enable cost-based vacuuming.
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delay feature. Positive values enable cost-based vacuuming.
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</para>
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</para>
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@ -2032,13 +2050,16 @@ include_dir 'conf.d'
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</term>
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</term>
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<listitem>
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<listitem>
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<para>
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<para>
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Specifies the delay (defaults to milliseconds) between activity rounds for the
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Specifies the delay between activity rounds for the
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background writer. In each round the writer issues writes
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background writer. In each round the writer issues writes
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for some number of dirty buffers (controllable by the
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for some number of dirty buffers (controllable by the
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following parameters). It then sleeps for <varname>bgwriter_delay</varname>
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following parameters). It then sleeps for
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duration, and repeats. When there are no dirty buffers in the
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the length of <varname>bgwriter_delay</varname>, and repeats.
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When there are no dirty buffers in the
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buffer pool, though, it goes into a longer sleep regardless of
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buffer pool, though, it goes into a longer sleep regardless of
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<varname>bgwriter_delay</varname>. The default value is 200
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<varname>bgwriter_delay</varname>.
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If this value is specified without units, it is taken as milliseconds.
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The default value is 200
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milliseconds (<literal>200ms</literal>). Note that on many systems, the
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milliseconds (<literal>200ms</literal>). Note that on many systems, the
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effective resolution of sleep delays is 10 milliseconds; setting
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effective resolution of sleep delays is 10 milliseconds; setting
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<varname>bgwriter_delay</varname> to a value that is not a multiple of 10
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<varname>bgwriter_delay</varname> to a value that is not a multiple of 10
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</term>
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</term>
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<listitem>
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<listitem>
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<para>
|
<para>
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Whenever more than <varname>bgwriter_flush_after</varname> bytes have
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Whenever more than this amount of data has
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been written by the background writer, attempt to force the OS to issue these
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been written by the background writer, attempt to force the OS to issue these
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writes to the underlying storage. Doing so will limit the amount of
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writes to the underlying storage. Doing so will limit the amount of
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dirty data in the kernel's page cache, reducing the likelihood of
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dirty data in the kernel's page cache, reducing the likelihood of
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also are some cases, especially with workloads that are bigger than
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also are some cases, especially with workloads that are bigger than
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<xref linkend="guc-shared-buffers"/>, but smaller than the OS's page
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<xref linkend="guc-shared-buffers"/>, but smaller than the OS's page
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cache, where performance might degrade. This setting may have no
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cache, where performance might degrade. This setting may have no
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effect on some platforms. The valid range is between
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effect on some platforms.
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If this value is specified without units, it is taken as blocks,
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that is <symbol>BLCKSZ</symbol> bytes, typically 8kB.
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The valid range is between
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<literal>0</literal>, which disables forced writeback, and
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<literal>0</literal>, which disables forced writeback, and
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<literal>2MB</literal>. The default is <literal>512kB</literal> on Linux,
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<literal>2MB</literal>. The default is <literal>512kB</literal> on Linux,
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<literal>0</literal> elsewhere. (If <symbol>BLCKSZ</symbol> is not 8kB,
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<literal>0</literal> elsewhere. (If <symbol>BLCKSZ</symbol> is not 8kB,
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</term>
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</term>
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<listitem>
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<listitem>
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<para>
|
<para>
|
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Whenever more than <varname>backend_flush_after</varname> bytes have
|
Whenever more than this amount of data has
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been written by a single backend, attempt to force the OS to issue
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been written by a single backend, attempt to force the OS to issue
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these writes to the underlying storage. Doing so will limit the
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these writes to the underlying storage. Doing so will limit the
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amount of dirty data in the kernel's page cache, reducing the
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amount of dirty data in the kernel's page cache, reducing the
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latency, but there also are some cases, especially with workloads
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latency, but there also are some cases, especially with workloads
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that are bigger than <xref linkend="guc-shared-buffers"/>, but smaller
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that are bigger than <xref linkend="guc-shared-buffers"/>, but smaller
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than the OS's page cache, where performance might degrade. This
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than the OS's page cache, where performance might degrade. This
|
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setting may have no effect on some platforms. The valid range is
|
setting may have no effect on some platforms.
|
||||||
|
If this value is specified without units, it is taken as blocks,
|
||||||
|
that is <symbol>BLCKSZ</symbol> bytes, typically 8kB.
|
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|
The valid range is
|
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between <literal>0</literal>, which disables forced writeback,
|
between <literal>0</literal>, which disables forced writeback,
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and <literal>2MB</literal>. The default is <literal>0</literal>, i.e., no
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and <literal>2MB</literal>. The default is <literal>0</literal>, i.e., no
|
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forced writeback. (If <symbol>BLCKSZ</symbol> is not 8kB,
|
forced writeback. (If <symbol>BLCKSZ</symbol> is not 8kB,
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@ -2350,13 +2377,10 @@ include_dir 'conf.d'
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</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
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<para>
|
<para>
|
||||||
Sets the minimum time that a snapshot can be used without risk of a
|
Sets the minimum amount of time that a query snapshot can be used
|
||||||
<literal>snapshot too old</literal> error occurring when using the snapshot.
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without risk of a <quote>snapshot too old</quote> error occurring
|
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This parameter can only be set at server start.
|
when using the snapshot. Data that has been dead for longer than
|
||||||
</para>
|
this threshold is allowed to be vacuumed away. This can help
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|
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<para>
|
|
||||||
Beyond the threshold, old data may be vacuumed away. This can help
|
|
||||||
prevent bloat in the face of snapshots which remain in use for a
|
prevent bloat in the face of snapshots which remain in use for a
|
||||||
long time. To prevent incorrect results due to cleanup of data which
|
long time. To prevent incorrect results due to cleanup of data which
|
||||||
would otherwise be visible to the snapshot, an error is generated
|
would otherwise be visible to the snapshot, an error is generated
|
||||||
@ -2366,10 +2390,15 @@ include_dir 'conf.d'
|
|||||||
</para>
|
</para>
|
||||||
|
|
||||||
<para>
|
<para>
|
||||||
A value of <literal>-1</literal> disables this feature, and is the default.
|
If this value is specified without units, it is taken as minutes.
|
||||||
|
A value of <literal>-1</literal> (the default) disables this feature,
|
||||||
|
effectively setting the snapshot age limit to infinity.
|
||||||
|
This parameter can only be set at server start.
|
||||||
|
</para>
|
||||||
|
|
||||||
|
<para>
|
||||||
Useful values for production work probably range from a small number
|
Useful values for production work probably range from a small number
|
||||||
of hours to a few days. The setting will be coerced to a granularity
|
of hours to a few days. Small values (such as <literal>0</literal> or
|
||||||
of minutes, and small numbers (such as <literal>0</literal> or
|
|
||||||
<literal>1min</literal>) are only allowed because they may sometimes be
|
<literal>1min</literal>) are only allowed because they may sometimes be
|
||||||
useful for testing. While a setting as high as <literal>60d</literal> is
|
useful for testing. While a setting as high as <literal>60d</literal> is
|
||||||
allowed, please note that in many workloads extreme bloat or
|
allowed, please note that in many workloads extreme bloat or
|
||||||
@ -2379,7 +2408,7 @@ include_dir 'conf.d'
|
|||||||
<para>
|
<para>
|
||||||
When this feature is enabled, freed space at the end of a relation
|
When this feature is enabled, freed space at the end of a relation
|
||||||
cannot be released to the operating system, since that could remove
|
cannot be released to the operating system, since that could remove
|
||||||
information needed to detect the <literal>snapshot too old</literal>
|
information needed to detect the <quote>snapshot too old</quote>
|
||||||
condition. All space allocated to a relation remains associated with
|
condition. All space allocated to a relation remains associated with
|
||||||
that relation for reuse only within that relation unless explicitly
|
that relation for reuse only within that relation unless explicitly
|
||||||
freed (for example, with <command>VACUUM FULL</command>).
|
freed (for example, with <command>VACUUM FULL</command>).
|
||||||
@ -2394,7 +2423,7 @@ include_dir 'conf.d'
|
|||||||
Some tables cannot safely be vacuumed early, and so will not be
|
Some tables cannot safely be vacuumed early, and so will not be
|
||||||
affected by this setting, such as system catalogs. For such tables
|
affected by this setting, such as system catalogs. For such tables
|
||||||
this setting will neither reduce bloat nor create a possibility
|
this setting will neither reduce bloat nor create a possibility
|
||||||
of a <literal>snapshot too old</literal> error on scanning.
|
of a <quote>snapshot too old</quote> error on scanning.
|
||||||
</para>
|
</para>
|
||||||
</listitem>
|
</listitem>
|
||||||
</varlistentry>
|
</varlistentry>
|
||||||
@ -2770,6 +2799,8 @@ include_dir 'conf.d'
|
|||||||
manually if the automatic choice is too large or too small,
|
manually if the automatic choice is too large or too small,
|
||||||
but any positive value less than <literal>32kB</literal> will be
|
but any positive value less than <literal>32kB</literal> will be
|
||||||
treated as <literal>32kB</literal>.
|
treated as <literal>32kB</literal>.
|
||||||
|
If this value is specified without units, it is taken as WAL blocks,
|
||||||
|
that is <symbol>XLOG_BLCKSZ</symbol> bytes, typically 8kB.
|
||||||
This parameter can only be set at server start.
|
This parameter can only be set at server start.
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
@ -2794,14 +2825,15 @@ include_dir 'conf.d'
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Specifies how often the WAL writer flushes WAL. After flushing WAL it
|
Specifies how often the WAL writer flushes WAL, in time terms.
|
||||||
sleeps for <varname>wal_writer_delay</varname> duration (defaults
|
After flushing WAL the writer sleeps for the length of time given
|
||||||
to milliseconds), unless woken up
|
by <varname>wal_writer_delay</varname>, unless woken up sooner
|
||||||
by an asynchronously committing transaction. If the last flush
|
by an asynchronously committing transaction. If the last flush
|
||||||
happened less than <varname>wal_writer_delay</varname> duration ago and
|
happened less than <varname>wal_writer_delay</varname> ago and less
|
||||||
less than <varname>wal_writer_flush_after</varname> bytes of WAL have been
|
than <varname>wal_writer_flush_after</varname> worth of WAL has been
|
||||||
produced since, then WAL is only written to the operating system, not
|
produced since, then WAL is only written to the operating system, not
|
||||||
flushed to disk.
|
flushed to disk.
|
||||||
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
The default value is 200 milliseconds (<literal>200ms</literal>). Note that
|
The default value is 200 milliseconds (<literal>200ms</literal>). Note that
|
||||||
on many systems, the effective resolution of sleep delays is 10
|
on many systems, the effective resolution of sleep delays is 10
|
||||||
milliseconds; setting <varname>wal_writer_delay</varname> to a value that is
|
milliseconds; setting <varname>wal_writer_delay</varname> to a value that is
|
||||||
@ -2820,14 +2852,17 @@ include_dir 'conf.d'
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Specifies how often the WAL writer flushes WAL. If the last flush
|
Specifies how often the WAL writer flushes WAL, in volume terms.
|
||||||
happened less than <varname>wal_writer_delay</varname> duration ago
|
If the last flush happened less
|
||||||
(defaults to milliseconds) and
|
than <varname>wal_writer_delay</varname> ago and less
|
||||||
less than <varname>wal_writer_flush_after</varname> bytes of WAL have been
|
than <varname>wal_writer_flush_after</varname> worth of WAL has been
|
||||||
produced since, then WAL is only written to the operating system, not
|
produced since, then WAL is only written to the operating system, not
|
||||||
flushed to disk. If <varname>wal_writer_flush_after</varname> is set
|
flushed to disk. If <varname>wal_writer_flush_after</varname> is set
|
||||||
to <literal>0</literal> then WAL data is flushed immediately. The default is
|
to <literal>0</literal> then WAL data is always flushed immediately.
|
||||||
<literal>1MB</literal>. This parameter can only be set in the
|
If this value is specified without units, it is taken as WAL blocks,
|
||||||
|
that is <symbol>XLOG_BLCKSZ</symbol> bytes, typically 8kB.
|
||||||
|
The default is <literal>1MB</literal>.
|
||||||
|
This parameter can only be set in the
|
||||||
<filename>postgresql.conf</filename> file or on the server command line.
|
<filename>postgresql.conf</filename> file or on the server command line.
|
||||||
</para>
|
</para>
|
||||||
</listitem>
|
</listitem>
|
||||||
@ -2841,18 +2876,19 @@ include_dir 'conf.d'
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
<varname>commit_delay</varname> adds a time delay, measured in
|
Setting <varname>commit_delay</varname> adds a time delay
|
||||||
microseconds, before a WAL flush is initiated. This can improve
|
before a WAL flush is initiated. This can improve
|
||||||
group commit throughput by allowing a larger number of transactions
|
group commit throughput by allowing a larger number of transactions
|
||||||
to commit via a single WAL flush, if system load is high enough
|
to commit via a single WAL flush, if system load is high enough
|
||||||
that additional transactions become ready to commit within the
|
that additional transactions become ready to commit within the
|
||||||
given interval. However, it also increases latency by up to
|
given interval. However, it also increases latency by up to the
|
||||||
<varname>commit_delay</varname> microseconds for each WAL
|
<varname>commit_delay</varname> for each WAL
|
||||||
flush. Because the delay is just wasted if no other transactions
|
flush. Because the delay is just wasted if no other transactions
|
||||||
become ready to commit, a delay is only performed if at least
|
become ready to commit, a delay is only performed if at least
|
||||||
<varname>commit_siblings</varname> other transactions are active
|
<varname>commit_siblings</varname> other transactions are active
|
||||||
when a flush is about to be initiated. Also, no delays are
|
when a flush is about to be initiated. Also, no delays are
|
||||||
performed if <varname>fsync</varname> is disabled.
|
performed if <varname>fsync</varname> is disabled.
|
||||||
|
If this value is specified without units, it is taken as microseconds.
|
||||||
The default <varname>commit_delay</varname> is zero (no delay).
|
The default <varname>commit_delay</varname> is zero (no delay).
|
||||||
Only superusers can change this setting.
|
Only superusers can change this setting.
|
||||||
</para>
|
</para>
|
||||||
@ -2900,7 +2936,8 @@ include_dir 'conf.d'
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Maximum duration between automatic WAL checkpoints (defaults to seconds).
|
Maximum time between automatic WAL checkpoints.
|
||||||
|
If this value is specified without units, it is taken as seconds.
|
||||||
The valid range is between 30 seconds and one day.
|
The valid range is between 30 seconds and one day.
|
||||||
The default is five minutes (<literal>5min</literal>).
|
The default is five minutes (<literal>5min</literal>).
|
||||||
Increasing this parameter can increase the amount of time needed
|
Increasing this parameter can increase the amount of time needed
|
||||||
@ -2935,8 +2972,8 @@ include_dir 'conf.d'
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Whenever more than <varname>checkpoint_flush_after</varname> bytes
|
Whenever more than this amount of data has been
|
||||||
have been written while performing a checkpoint, attempt to force the
|
written while performing a checkpoint, attempt to force the
|
||||||
OS to issue these writes to the underlying storage. Doing so will
|
OS to issue these writes to the underlying storage. Doing so will
|
||||||
limit the amount of dirty data in the kernel's page cache, reducing
|
limit the amount of dirty data in the kernel's page cache, reducing
|
||||||
the likelihood of stalls when an <function>fsync</function> is issued at the end of the
|
the likelihood of stalls when an <function>fsync</function> is issued at the end of the
|
||||||
@ -2945,7 +2982,10 @@ include_dir 'conf.d'
|
|||||||
latency, but there also are some cases, especially with workloads
|
latency, but there also are some cases, especially with workloads
|
||||||
that are bigger than <xref linkend="guc-shared-buffers"/>, but smaller
|
that are bigger than <xref linkend="guc-shared-buffers"/>, but smaller
|
||||||
than the OS's page cache, where performance might degrade. This
|
than the OS's page cache, where performance might degrade. This
|
||||||
setting may have no effect on some platforms. The valid range is
|
setting may have no effect on some platforms.
|
||||||
|
If this value is specified without units, it is taken as blocks,
|
||||||
|
that is <symbol>BLCKSZ</symbol> bytes, typically 8kB.
|
||||||
|
The valid range is
|
||||||
between <literal>0</literal>, which disables forced writeback,
|
between <literal>0</literal>, which disables forced writeback,
|
||||||
and <literal>2MB</literal>. The default is <literal>256kB</literal> on
|
and <literal>2MB</literal>. The default is <literal>256kB</literal> on
|
||||||
Linux, <literal>0</literal> elsewhere. (If <symbol>BLCKSZ</symbol> is not
|
Linux, <literal>0</literal> elsewhere. (If <symbol>BLCKSZ</symbol> is not
|
||||||
@ -2966,9 +3006,11 @@ include_dir 'conf.d'
|
|||||||
<para>
|
<para>
|
||||||
Write a message to the server log if checkpoints caused by
|
Write a message to the server log if checkpoints caused by
|
||||||
the filling of WAL segment files happen closer together
|
the filling of WAL segment files happen closer together
|
||||||
than this many seconds (which suggests that
|
than this amount of time (which suggests that
|
||||||
<varname>max_wal_size</varname> ought to be raised). The default is
|
<varname>max_wal_size</varname> ought to be raised).
|
||||||
30 seconds (<literal>30s</literal>). Zero disables the warning.
|
If this value is specified without units, it is taken as seconds.
|
||||||
|
The default is 30 seconds (<literal>30s</literal>).
|
||||||
|
Zero disables the warning.
|
||||||
No warnings will be generated if <varname>checkpoint_timeout</varname>
|
No warnings will be generated if <varname>checkpoint_timeout</varname>
|
||||||
is less than <varname>checkpoint_warning</varname>.
|
is less than <varname>checkpoint_warning</varname>.
|
||||||
This parameter can only be set in the <filename>postgresql.conf</filename>
|
This parameter can only be set in the <filename>postgresql.conf</filename>
|
||||||
@ -2987,9 +3029,11 @@ include_dir 'conf.d'
|
|||||||
<para>
|
<para>
|
||||||
Maximum size to let the WAL grow to between automatic WAL
|
Maximum size to let the WAL grow to between automatic WAL
|
||||||
checkpoints. This is a soft limit; WAL size can exceed
|
checkpoints. This is a soft limit; WAL size can exceed
|
||||||
<varname>max_wal_size</varname> under special circumstances, like
|
<varname>max_wal_size</varname> under special circumstances, such as
|
||||||
under heavy load, a failing <varname>archive_command</varname>, or a high
|
heavy load, a failing <varname>archive_command</varname>, or a high
|
||||||
<varname>wal_keep_segments</varname> setting. The default is 1 GB.
|
<varname>wal_keep_segments</varname> setting.
|
||||||
|
If this value is specified without units, it is taken as megabytes.
|
||||||
|
The default is 1 GB.
|
||||||
Increasing this parameter can increase the amount of time needed for
|
Increasing this parameter can increase the amount of time needed for
|
||||||
crash recovery.
|
crash recovery.
|
||||||
This parameter can only be set in the <filename>postgresql.conf</filename>
|
This parameter can only be set in the <filename>postgresql.conf</filename>
|
||||||
@ -3010,7 +3054,9 @@ include_dir 'conf.d'
|
|||||||
always recycled for future use at a checkpoint, rather than removed.
|
always recycled for future use at a checkpoint, rather than removed.
|
||||||
This can be used to ensure that enough WAL space is reserved to
|
This can be used to ensure that enough WAL space is reserved to
|
||||||
handle spikes in WAL usage, for example when running large batch
|
handle spikes in WAL usage, for example when running large batch
|
||||||
jobs. The default is 80 MB.
|
jobs.
|
||||||
|
If this value is specified without units, it is taken as megabytes.
|
||||||
|
The default is 80 MB.
|
||||||
This parameter can only be set in the <filename>postgresql.conf</filename>
|
This parameter can only be set in the <filename>postgresql.conf</filename>
|
||||||
file or on the server command line.
|
file or on the server command line.
|
||||||
</para>
|
</para>
|
||||||
@ -3105,7 +3151,7 @@ include_dir 'conf.d'
|
|||||||
data can be, you can set <varname>archive_timeout</varname> to force the
|
data can be, you can set <varname>archive_timeout</varname> to force the
|
||||||
server to switch to a new WAL segment file periodically. When this
|
server to switch to a new WAL segment file periodically. When this
|
||||||
parameter is greater than zero, the server will switch to a new
|
parameter is greater than zero, the server will switch to a new
|
||||||
segment file whenever this many seconds have elapsed since the last
|
segment file whenever this amount of time has elapsed since the last
|
||||||
segment file switch, and there has been any database activity,
|
segment file switch, and there has been any database activity,
|
||||||
including a single checkpoint (checkpoints are skipped if there is
|
including a single checkpoint (checkpoints are skipped if there is
|
||||||
no database activity). Note that archived files that are closed
|
no database activity). Note that archived files that are closed
|
||||||
@ -3116,6 +3162,7 @@ include_dir 'conf.d'
|
|||||||
usually reasonable. You should consider using streaming replication,
|
usually reasonable. You should consider using streaming replication,
|
||||||
instead of archiving, if you want data to be copied off the master
|
instead of archiving, if you want data to be copied off the master
|
||||||
server more quickly than that.
|
server more quickly than that.
|
||||||
|
If this value is specified without units, it is taken as seconds.
|
||||||
This parameter can only be set in the
|
This parameter can only be set in the
|
||||||
<filename>postgresql.conf</filename> file or on the server command line.
|
<filename>postgresql.conf</filename> file or on the server command line.
|
||||||
</para>
|
</para>
|
||||||
@ -3674,11 +3721,15 @@ restore_command = 'copy "C:\\server\\archivedir\\%f" "%p"' # Windows
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Terminate replication connections that are inactive longer
|
Terminate replication connections that are inactive for longer
|
||||||
than the specified duration (defaults to milliseconds). This is useful for
|
than this amount of time. This is useful for
|
||||||
the sending server to detect a standby crash or network outage.
|
the sending server to detect a standby crash or network outage.
|
||||||
A value of zero disables the timeout mechanism. The default value
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
is 60 seconds. With a cluster distributed across multiple geographic
|
The default value is 60 seconds.
|
||||||
|
A value of zero disables the timeout mechanism.
|
||||||
|
</para>
|
||||||
|
<para>
|
||||||
|
With a cluster distributed across multiple geographic
|
||||||
locations, using different values per location brings more flexibility
|
locations, using different values per location brings more flexibility
|
||||||
in the cluster management. A smaller value is useful for faster
|
in the cluster management. A smaller value is useful for faster
|
||||||
failure detection with a standby having a low-latency network
|
failure detection with a standby having a low-latency network
|
||||||
@ -4005,7 +4056,8 @@ ANY <replaceable class="parameter">num_sync</replaceable> ( <replaceable class="
|
|||||||
<xref linkend="hot-standby-conflict"/>.
|
<xref linkend="hot-standby-conflict"/>.
|
||||||
<varname>max_standby_archive_delay</varname> applies when WAL data is
|
<varname>max_standby_archive_delay</varname> applies when WAL data is
|
||||||
being read from WAL archive (and is therefore not current).
|
being read from WAL archive (and is therefore not current).
|
||||||
The default is 30 seconds. Units are milliseconds if not specified.
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
|
The default is 30 seconds.
|
||||||
A value of -1 allows the standby to wait forever for conflicting
|
A value of -1 allows the standby to wait forever for conflicting
|
||||||
queries to complete.
|
queries to complete.
|
||||||
This parameter can only be set in the <filename>postgresql.conf</filename>
|
This parameter can only be set in the <filename>postgresql.conf</filename>
|
||||||
@ -4036,7 +4088,8 @@ ANY <replaceable class="parameter">num_sync</replaceable> ( <replaceable class="
|
|||||||
<xref linkend="hot-standby-conflict"/>.
|
<xref linkend="hot-standby-conflict"/>.
|
||||||
<varname>max_standby_streaming_delay</varname> applies when WAL data is
|
<varname>max_standby_streaming_delay</varname> applies when WAL data is
|
||||||
being received via streaming replication.
|
being received via streaming replication.
|
||||||
The default is 30 seconds. Units are milliseconds if not specified.
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
|
The default is 30 seconds.
|
||||||
A value of -1 allows the standby to wait forever for conflicting
|
A value of -1 allows the standby to wait forever for conflicting
|
||||||
queries to complete.
|
queries to complete.
|
||||||
This parameter can only be set in the <filename>postgresql.conf</filename>
|
This parameter can only be set in the <filename>postgresql.conf</filename>
|
||||||
@ -4071,13 +4124,16 @@ ANY <replaceable class="parameter">num_sync</replaceable> ( <replaceable class="
|
|||||||
the last write-ahead log location it has written, the last position it
|
the last write-ahead log location it has written, the last position it
|
||||||
has flushed to disk, and the last position it has applied.
|
has flushed to disk, and the last position it has applied.
|
||||||
This parameter's
|
This parameter's
|
||||||
value is the maximum interval, in seconds, between reports. Updates are
|
value is the maximum amount of time between reports. Updates are
|
||||||
sent each time the write or flush positions change, or at least as
|
sent each time the write or flush positions change, or at least as
|
||||||
often as specified by this parameter. Thus, the apply position may
|
often as specified by this parameter. Thus, the apply position may
|
||||||
lag slightly behind the true position. Setting this parameter to zero
|
lag slightly behind the true position.
|
||||||
disables status updates completely. This parameter can only be set in
|
If this value is specified without units, it is taken as seconds.
|
||||||
the <filename>postgresql.conf</filename> file or on the server command line.
|
|
||||||
The default value is 10 seconds.
|
The default value is 10 seconds.
|
||||||
|
Setting this parameter to zero disables status updates completely.
|
||||||
|
This parameter can only be set in
|
||||||
|
the <filename>postgresql.conf</filename> file or on the server
|
||||||
|
command line.
|
||||||
</para>
|
</para>
|
||||||
</listitem>
|
</listitem>
|
||||||
</varlistentry>
|
</varlistentry>
|
||||||
@ -4126,14 +4182,16 @@ ANY <replaceable class="parameter">num_sync</replaceable> ( <replaceable class="
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Terminate replication connections that are inactive longer
|
Terminate replication connections that are inactive for longer
|
||||||
than the specified duration (defaults to milliseconds). This is useful for
|
than this amount of time. This is useful for
|
||||||
the receiving standby server to detect a primary node crash or network
|
the receiving standby server to detect a primary node crash or network
|
||||||
outage.
|
outage.
|
||||||
A value of zero disables the timeout mechanism. This parameter
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
can only be set in
|
|
||||||
the <filename>postgresql.conf</filename> file or on the server command line.
|
|
||||||
The default value is 60 seconds.
|
The default value is 60 seconds.
|
||||||
|
A value of zero disables the timeout mechanism.
|
||||||
|
This parameter can only be set in
|
||||||
|
the <filename>postgresql.conf</filename> file or on the server
|
||||||
|
command line.
|
||||||
</para>
|
</para>
|
||||||
</listitem>
|
</listitem>
|
||||||
</varlistentry>
|
</varlistentry>
|
||||||
@ -4146,12 +4204,15 @@ ANY <replaceable class="parameter">num_sync</replaceable> ( <replaceable class="
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Specify how long the standby server should wait when WAL data is not
|
Specifies how long the standby server should wait when WAL data is not
|
||||||
available from any sources (streaming replication,
|
available from any sources (streaming replication,
|
||||||
local <filename>pg_wal</filename> or WAL archive) before retrying to
|
local <filename>pg_wal</filename> or WAL archive) before trying
|
||||||
retrieve WAL data. This parameter can only be set in the
|
again to retrieve WAL data.
|
||||||
<filename>postgresql.conf</filename> file or on the server command line.
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
The default value is 5 seconds. Units are milliseconds if not specified.
|
The default value is 5 seconds.
|
||||||
|
This parameter can only be set in
|
||||||
|
the <filename>postgresql.conf</filename> file or on the server
|
||||||
|
command line.
|
||||||
</para>
|
</para>
|
||||||
<para>
|
<para>
|
||||||
This parameter is useful in configurations where a node in recovery
|
This parameter is useful in configurations where a node in recovery
|
||||||
@ -4178,11 +4239,13 @@ ANY <replaceable class="parameter">num_sync</replaceable> ( <replaceable class="
|
|||||||
By default, a standby server restores WAL records from the
|
By default, a standby server restores WAL records from the
|
||||||
sending server as soon as possible. It may be useful to have a time-delayed
|
sending server as soon as possible. It may be useful to have a time-delayed
|
||||||
copy of the data, offering opportunities to correct data loss errors.
|
copy of the data, offering opportunities to correct data loss errors.
|
||||||
This parameter allows you to delay recovery by a fixed period of time,
|
This parameter allows you to delay recovery by a specified amount
|
||||||
measured in milliseconds if no unit is specified. For example, if
|
of time. For example, if
|
||||||
you set this parameter to <literal>5min</literal>, the standby will
|
you set this parameter to <literal>5min</literal>, the standby will
|
||||||
replay each transaction commit only when the system time on the standby
|
replay each transaction commit only when the system time on the standby
|
||||||
is at least five minutes past the commit time reported by the master.
|
is at least five minutes past the commit time reported by the master.
|
||||||
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
|
The default is zero, adding no delay.
|
||||||
</para>
|
</para>
|
||||||
<para>
|
<para>
|
||||||
It is possible that the replication delay between servers exceeds the
|
It is possible that the replication delay between servers exceeds the
|
||||||
@ -4795,8 +4858,10 @@ ANY <replaceable class="parameter">num_sync</replaceable> ( <replaceable class="
|
|||||||
for a parallel scan to be considered. For a parallel sequential scan,
|
for a parallel scan to be considered. For a parallel sequential scan,
|
||||||
the amount of table data scanned is always equal to the size of the
|
the amount of table data scanned is always equal to the size of the
|
||||||
table, but when indexes are used the amount of table data
|
table, but when indexes are used the amount of table data
|
||||||
scanned will normally be less. The default is 8
|
scanned will normally be less.
|
||||||
megabytes (<literal>8MB</literal>).
|
If this value is specified without units, it is taken as blocks,
|
||||||
|
that is <symbol>BLCKSZ</symbol> bytes, typically 8kB.
|
||||||
|
The default is 8 megabytes (<literal>8MB</literal>).
|
||||||
</para>
|
</para>
|
||||||
</listitem>
|
</listitem>
|
||||||
</varlistentry>
|
</varlistentry>
|
||||||
@ -4813,7 +4878,10 @@ ANY <replaceable class="parameter">num_sync</replaceable> ( <replaceable class="
|
|||||||
for a parallel scan to be considered. Note that a parallel index scan
|
for a parallel scan to be considered. Note that a parallel index scan
|
||||||
typically won't touch the entire index; it is the number of pages
|
typically won't touch the entire index; it is the number of pages
|
||||||
which the planner believes will actually be touched by the scan which
|
which the planner believes will actually be touched by the scan which
|
||||||
is relevant. The default is 512 kilobytes (<literal>512kB</literal>).
|
is relevant.
|
||||||
|
If this value is specified without units, it is taken as blocks,
|
||||||
|
that is <symbol>BLCKSZ</symbol> bytes, typically 8kB.
|
||||||
|
The default is 512 kilobytes (<literal>512kB</literal>).
|
||||||
</para>
|
</para>
|
||||||
</listitem>
|
</listitem>
|
||||||
</varlistentry>
|
</varlistentry>
|
||||||
@ -4842,8 +4910,12 @@ ANY <replaceable class="parameter">num_sync</replaceable> ( <replaceable class="
|
|||||||
memory allocated by <productname>PostgreSQL</productname>, nor
|
memory allocated by <productname>PostgreSQL</productname>, nor
|
||||||
does it reserve kernel disk cache; it is used only for estimation
|
does it reserve kernel disk cache; it is used only for estimation
|
||||||
purposes. The system also does not assume data remains in
|
purposes. The system also does not assume data remains in
|
||||||
the disk cache between queries. The default is 4 gigabytes
|
the disk cache between queries.
|
||||||
(<literal>4GB</literal>).
|
If this value is specified without units, it is taken as blocks,
|
||||||
|
that is <symbol>BLCKSZ</symbol> bytes, typically 8kB.
|
||||||
|
The default is 4 gigabytes (<literal>4GB</literal>).
|
||||||
|
(If <symbol>BLCKSZ</symbol> is not 8kB, the default value scales
|
||||||
|
proportionally to it.)
|
||||||
</para>
|
</para>
|
||||||
</listitem>
|
</listitem>
|
||||||
</varlistentry>
|
</varlistentry>
|
||||||
@ -5601,10 +5673,11 @@ local0.* /var/log/postgresql
|
|||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
When <varname>logging_collector</varname> is enabled,
|
When <varname>logging_collector</varname> is enabled,
|
||||||
this parameter determines the maximum lifetime of an individual log file.
|
this parameter determines the maximum amount of time to use an
|
||||||
After this many minutes have elapsed, a new log file will
|
individual log file, after which a new log file will be created.
|
||||||
be created. Set to zero to disable time-based creation of
|
If this value is specified without units, it is taken as minutes.
|
||||||
new log files.
|
The default is 24 hours.
|
||||||
|
Set to zero to disable time-based creation of new log files.
|
||||||
This parameter can only be set in the <filename>postgresql.conf</filename>
|
This parameter can only be set in the <filename>postgresql.conf</filename>
|
||||||
file or on the server command line.
|
file or on the server command line.
|
||||||
</para>
|
</para>
|
||||||
@ -5621,9 +5694,11 @@ local0.* /var/log/postgresql
|
|||||||
<para>
|
<para>
|
||||||
When <varname>logging_collector</varname> is enabled,
|
When <varname>logging_collector</varname> is enabled,
|
||||||
this parameter determines the maximum size of an individual log file.
|
this parameter determines the maximum size of an individual log file.
|
||||||
After this many bytes (default units is kilobytes) have been emitted into a log file,
|
After this amount of data has been emitted into a log file,
|
||||||
a new log file will be created. Set to zero to disable size-based
|
a new log file will be created.
|
||||||
creation of new log files.
|
If this value is specified without units, it is taken as kilobytes.
|
||||||
|
The default is 10 megabytes.
|
||||||
|
Set to zero to disable size-based creation of new log files.
|
||||||
This parameter can only be set in the <filename>postgresql.conf</filename>
|
This parameter can only be set in the <filename>postgresql.conf</filename>
|
||||||
file or on the server command line.
|
file or on the server command line.
|
||||||
</para>
|
</para>
|
||||||
@ -5864,8 +5939,9 @@ local0.* /var/log/postgresql
|
|||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Causes the duration of each completed statement to be logged
|
Causes the duration of each completed statement to be logged
|
||||||
if the statement ran for at least the specified duration (defaults
|
if the statement ran for at least the specified amount of time.
|
||||||
to milliseconds). Setting this to zero prints all statement durations.
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
|
Setting this to zero prints all statement durations.
|
||||||
Minus-one (the default) disables logging statement durations.
|
Minus-one (the default) disables logging statement durations.
|
||||||
For example, if you set it to <literal>250ms</literal>
|
For example, if you set it to <literal>250ms</literal>
|
||||||
then all SQL statements that run 250ms or longer will be
|
then all SQL statements that run 250ms or longer will be
|
||||||
@ -6488,11 +6564,13 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
|
|||||||
Controls logging of temporary file names and sizes.
|
Controls logging of temporary file names and sizes.
|
||||||
Temporary files can be
|
Temporary files can be
|
||||||
created for sorts, hashes, and temporary query results.
|
created for sorts, hashes, and temporary query results.
|
||||||
A log entry is made for each temporary file when it is deleted.
|
If enabled by this setting, a log entry is emitted for each
|
||||||
|
temporary file when it is deleted.
|
||||||
A value of zero logs all temporary file information, while positive
|
A value of zero logs all temporary file information, while positive
|
||||||
values log only files whose size is greater than or equal to
|
values log only files whose size is greater than or equal to
|
||||||
the specified number of bytes (default units is kilobytes). The
|
the specified amount of data.
|
||||||
default setting is -1, which disables such logging.
|
If this value is specified without units, it is taken as kilobytes.
|
||||||
|
The default setting is -1, which disables such logging.
|
||||||
Only superusers can change this setting.
|
Only superusers can change this setting.
|
||||||
</para>
|
</para>
|
||||||
</listitem>
|
</listitem>
|
||||||
@ -6748,11 +6826,12 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Specifies the number of bytes reserved to track the currently
|
Specifies the amount of memory reserved to store the text of the
|
||||||
executing command for each active session, for the
|
currently executing command for each active session, for the
|
||||||
<structname>pg_stat_activity</structname>.<structfield>query</structfield> field.
|
<structname>pg_stat_activity</structname>.<structfield>query</structfield> field.
|
||||||
The default value is 1024. This parameter can only be set at server
|
If this value is specified without units, it is taken as bytes.
|
||||||
start.
|
The default value is 1024 bytes.
|
||||||
|
This parameter can only be set at server start.
|
||||||
</para>
|
</para>
|
||||||
</listitem>
|
</listitem>
|
||||||
</varlistentry>
|
</varlistentry>
|
||||||
@ -6939,9 +7018,11 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
|
|||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Causes each action executed by autovacuum to be logged if it ran for at
|
Causes each action executed by autovacuum to be logged if it ran for at
|
||||||
least the specified duration (defaults to milliseconds). Setting this to zero logs
|
least the specified amount of time. Setting this to zero logs
|
||||||
all autovacuum actions. <literal>-1</literal> (the default) disables
|
all autovacuum actions. <literal>-1</literal> (the default) disables
|
||||||
logging autovacuum actions. For example, if you set this to
|
logging autovacuum actions.
|
||||||
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
|
For example, if you set this to
|
||||||
<literal>250ms</literal> then all automatic vacuums and analyzes that run
|
<literal>250ms</literal> then all automatic vacuums and analyzes that run
|
||||||
250ms or longer will be logged. In addition, when this parameter is
|
250ms or longer will be logged. In addition, when this parameter is
|
||||||
set to any value other than <literal>-1</literal>, a message will be
|
set to any value other than <literal>-1</literal>, a message will be
|
||||||
@ -6981,8 +7062,9 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
|
|||||||
Specifies the minimum delay between autovacuum runs on any given
|
Specifies the minimum delay between autovacuum runs on any given
|
||||||
database. In each round the daemon examines the
|
database. In each round the daemon examines the
|
||||||
database and issues <command>VACUUM</command> and <command>ANALYZE</command> commands
|
database and issues <command>VACUUM</command> and <command>ANALYZE</command> commands
|
||||||
as needed for tables in that database. The delay is measured
|
as needed for tables in that database.
|
||||||
in seconds, and the default is one minute (<literal>1min</literal>).
|
If this value is specified without units, it is taken as seconds.
|
||||||
|
The default is one minute (<literal>1min</literal>).
|
||||||
This parameter can only be set in the <filename>postgresql.conf</filename>
|
This parameter can only be set in the <filename>postgresql.conf</filename>
|
||||||
file or on the server command line.
|
file or on the server command line.
|
||||||
</para>
|
</para>
|
||||||
@ -7141,6 +7223,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
|
|||||||
Specifies the cost delay value that will be used in automatic
|
Specifies the cost delay value that will be used in automatic
|
||||||
<command>VACUUM</command> operations. If -1 is specified, the regular
|
<command>VACUUM</command> operations. If -1 is specified, the regular
|
||||||
<xref linkend="guc-vacuum-cost-delay"/> value will be used.
|
<xref linkend="guc-vacuum-cost-delay"/> value will be used.
|
||||||
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
The default value is 2 milliseconds.
|
The default value is 2 milliseconds.
|
||||||
This parameter can only be set in the <filename>postgresql.conf</filename>
|
This parameter can only be set in the <filename>postgresql.conf</filename>
|
||||||
file or on the server command line;
|
file or on the server command line;
|
||||||
@ -7592,11 +7675,20 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Abort any statement that takes more than the specified duration
|
Abort any statement that takes more than the specified amount of time.
|
||||||
(defaults to milliseconds), starting from the time the command arrives at the server
|
If <varname>log_min_error_statement</varname> is set
|
||||||
from the client. If <varname>log_min_error_statement</varname> is set to
|
to <literal>ERROR</literal> or lower, the statement that timed out
|
||||||
<literal>ERROR</literal> or lower, the statement that timed out will also be
|
will also be logged.
|
||||||
logged. A value of zero (the default) turns this off.
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
|
A value of zero (the default) disables the timeout.
|
||||||
|
</para>
|
||||||
|
|
||||||
|
<para>
|
||||||
|
The timeout is measured from the time a command arrives at the
|
||||||
|
server until it is completed by the server.
|
||||||
|
In extended query protocol, the timeout starts running when any
|
||||||
|
query-related message (Parse, Bind, Execute, Describe) arrives, and
|
||||||
|
it is cancelled by completion of an Execute or Sync message.
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
<para>
|
<para>
|
||||||
@ -7615,13 +7707,15 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Abort any statement that waits longer than the specified duration
|
Abort any statement that waits longer than the specified amount of
|
||||||
(defaults to milliseconds) while attempting to acquire a lock on a table, index,
|
time while attempting to acquire a lock on a table, index,
|
||||||
row, or other database object. The time limit applies separately to
|
row, or other database object. The time limit applies separately to
|
||||||
each lock acquisition attempt. The limit applies both to explicit
|
each lock acquisition attempt. The limit applies both to explicit
|
||||||
locking requests (such as <command>LOCK TABLE</command>, or <command>SELECT
|
locking requests (such as <command>LOCK TABLE</command>, or <command>SELECT
|
||||||
FOR UPDATE</command> without <literal>NOWAIT</literal>) and to implicitly-acquired
|
FOR UPDATE</command> without <literal>NOWAIT</literal>) and to implicitly-acquired
|
||||||
locks. A value of zero (the default) turns this off.
|
locks.
|
||||||
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
|
A value of zero (the default) disables the timeout.
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
<para>
|
<para>
|
||||||
@ -7651,13 +7745,14 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
|
|||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Terminate any session with an open transaction that has been idle for
|
Terminate any session with an open transaction that has been idle for
|
||||||
longer than the specified duration (defaults to milliseconds). This allows any
|
longer than the specified amount of time. This allows any
|
||||||
locks held by that session to be released and the connection slot to be reused;
|
locks held by that session to be released and the connection slot to be reused;
|
||||||
it also allows tuples visible only to this transaction to be vacuumed. See
|
it also allows tuples visible only to this transaction to be vacuumed. See
|
||||||
<xref linkend="routine-vacuuming"/> for more details about this.
|
<xref linkend="routine-vacuuming"/> for more details about this.
|
||||||
</para>
|
</para>
|
||||||
<para>
|
<para>
|
||||||
The default value of 0 disables this feature.
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
|
A value of zero (the default) disables the timeout.
|
||||||
</para>
|
</para>
|
||||||
</listitem>
|
</listitem>
|
||||||
</varlistentry>
|
</varlistentry>
|
||||||
@ -7884,10 +7979,11 @@ SET XML OPTION { DOCUMENT | CONTENT };
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
Sets the maximum size of the GIN pending list which is used
|
Sets the maximum size of a GIN index's pending list, which is used
|
||||||
when <literal>fastupdate</literal> is enabled. If the list grows
|
when <literal>fastupdate</literal> is enabled. If the list grows
|
||||||
larger than this maximum size, it is cleaned up by moving
|
larger than this maximum size, it is cleaned up by moving
|
||||||
the entries in it to the main GIN data structure in bulk.
|
the entries in it to the index's main GIN data structure in bulk.
|
||||||
|
If this value is specified without units, it is taken as kilobytes.
|
||||||
The default is four megabytes (<literal>4MB</literal>). This setting
|
The default is four megabytes (<literal>4MB</literal>). This setting
|
||||||
can be overridden for individual GIN indexes by changing
|
can be overridden for individual GIN indexes by changing
|
||||||
index storage parameters.
|
index storage parameters.
|
||||||
@ -8488,7 +8584,7 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir'
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
This is the duration (defaults to milliseconds), to wait on a lock
|
This is the amount of time to wait on a lock
|
||||||
before checking to see if there is a deadlock condition. The
|
before checking to see if there is a deadlock condition. The
|
||||||
check for deadlock is relatively expensive, so the server doesn't run
|
check for deadlock is relatively expensive, so the server doesn't run
|
||||||
it every time it waits for a lock. We optimistically assume
|
it every time it waits for a lock. We optimistically assume
|
||||||
@ -8496,7 +8592,9 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir'
|
|||||||
just wait on the lock for a while before checking for a
|
just wait on the lock for a while before checking for a
|
||||||
deadlock. Increasing this value reduces the amount of time
|
deadlock. Increasing this value reduces the amount of time
|
||||||
wasted in needless deadlock checks, but slows down reporting of
|
wasted in needless deadlock checks, but slows down reporting of
|
||||||
real deadlock errors. The default is one second (<literal>1s</literal>),
|
real deadlock errors.
|
||||||
|
If this value is specified without units, it is taken as milliseconds.
|
||||||
|
The default is one second (<literal>1s</literal>),
|
||||||
which is probably about the smallest value you would want in
|
which is probably about the smallest value you would want in
|
||||||
practice. On a heavily loaded server you might want to raise it.
|
practice. On a heavily loaded server you might want to raise it.
|
||||||
Ideally the setting should exceed your typical transaction time,
|
Ideally the setting should exceed your typical transaction time,
|
||||||
@ -8507,7 +8605,7 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir'
|
|||||||
|
|
||||||
<para>
|
<para>
|
||||||
When <xref linkend="guc-log-lock-waits"/> is set,
|
When <xref linkend="guc-log-lock-waits"/> is set,
|
||||||
this parameter also determines the duration to wait before
|
this parameter also determines the amount of time to wait before
|
||||||
a log message is issued about the lock wait. If you are trying
|
a log message is issued about the lock wait. If you are trying
|
||||||
to investigate locking delays you might want to set a shorter than
|
to investigate locking delays you might want to set a shorter than
|
||||||
normal <varname>deadlock_timeout</varname>.
|
normal <varname>deadlock_timeout</varname>.
|
||||||
@ -9325,12 +9423,13 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir'
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
If nonzero, a delay of this duration occurs when a new
|
The amount of time to delay when a new
|
||||||
server process is started, after it conducts the
|
server process is started, after it conducts the
|
||||||
authentication procedure. This is intended to give developers an
|
authentication procedure. This is intended to give developers an
|
||||||
opportunity to attach to the server process with a debugger.
|
opportunity to attach to the server process with a debugger.
|
||||||
This parameter defaults to seconds and cannot be changed after
|
If this value is specified without units, it is taken as seconds.
|
||||||
session start.
|
A value of zero (the default) disables the delay.
|
||||||
|
This parameter cannot be changed after session start.
|
||||||
</para>
|
</para>
|
||||||
</listitem>
|
</listitem>
|
||||||
</varlistentry>
|
</varlistentry>
|
||||||
@ -9343,14 +9442,15 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir'
|
|||||||
</term>
|
</term>
|
||||||
<listitem>
|
<listitem>
|
||||||
<para>
|
<para>
|
||||||
If nonzero, a delay of this duration occurs just after a
|
The amount of time to delay just after a
|
||||||
new server process is forked, before it conducts the
|
new server process is forked, before it conducts the
|
||||||
authentication procedure. This is intended to give developers an
|
authentication procedure. This is intended to give developers an
|
||||||
opportunity to attach to the server process with a debugger to
|
opportunity to attach to the server process with a debugger to
|
||||||
trace down misbehavior in authentication.
|
trace down misbehavior in authentication.
|
||||||
This parameter defaults to seconds and can only be set in the
|
If this value is specified without units, it is taken as seconds.
|
||||||
<filename>postgresql.conf</filename> file or on the server
|
A value of zero (the default) disables the delay.
|
||||||
command line.
|
This parameter can only be set in the <filename>postgresql.conf</filename>
|
||||||
|
file or on the server command line.
|
||||||
</para>
|
</para>
|
||||||
</listitem>
|
</listitem>
|
||||||
</varlistentry>
|
</varlistentry>
|
||||||
|
Loading…
Reference in New Issue
Block a user