diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/config.sgml | 23 | ||||
| -rw-r--r-- | doc/src/sgml/ref/create_table.sgml | 2 |
2 files changed, 14 insertions, 11 deletions
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 7bbe8f590b6..c12170b4b63 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -91,7 +91,9 @@ <listitem> <para> - Valid time units are <literal>ms</literal> (milliseconds), + Valid time units are + <literal>us</literal> (microseconds), + <literal>ms</literal> (milliseconds), <literal>s</literal> (seconds), <literal>min</literal> (minutes), <literal>h</literal> (hours), and <literal>d</literal> (days). </para> @@ -1845,7 +1847,7 @@ include_dir 'conf.d' <variablelist> <varlistentry id="guc-vacuum-cost-delay" xreflabel="vacuum_cost_delay"> - <term><varname>vacuum_cost_delay</varname> (<type>integer</type>) + <term><varname>vacuum_cost_delay</varname> (<type>floating point</type>) <indexterm> <primary><varname>vacuum_cost_delay</varname> configuration parameter</primary> </indexterm> @@ -1856,18 +1858,19 @@ include_dir 'conf.d' when the cost limit has been exceeded. The default value is zero, which disables the cost-based vacuum delay feature. Positive values enable cost-based vacuuming. - Note that on many systems, the effective resolution - of sleep delays is 10 milliseconds; setting - <varname>vacuum_cost_delay</varname> to a value that is - not a multiple of 10 might have the same results as setting it - to the next higher multiple of 10. </para> <para> When using cost-based vacuuming, appropriate values for <varname>vacuum_cost_delay</varname> are usually quite small, perhaps - 10 or 20 milliseconds. Adjusting vacuum's resource consumption - is best done by changing the other vacuum cost parameters. + less than 1 millisecond. While <varname>vacuum_cost_delay</varname> + can be set to fractional-millisecond values, such delays may not be + measured accurately on older platforms. On such platforms, + increasing <command>VACUUM</command>'s throttled resource consumption + above what you get at 1ms will require changing the other vacuum cost + parameters. You should, nonetheless, + keep <varname>vacuum_cost_delay</varname> as small as your platform + will consistently measure; large delays are not helpful. </para> </listitem> </varlistentry> @@ -7020,7 +7023,7 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; </varlistentry> <varlistentry id="guc-autovacuum-vacuum-cost-delay" xreflabel="autovacuum_vacuum_cost_delay"> - <term><varname>autovacuum_vacuum_cost_delay</varname> (<type>integer</type>) + <term><varname>autovacuum_vacuum_cost_delay</varname> (<type>floating point</type>) <indexterm> <primary><varname>autovacuum_vacuum_cost_delay</varname> configuration parameter</primary> </indexterm> diff --git a/doc/src/sgml/ref/create_table.sgml b/doc/src/sgml/ref/create_table.sgml index 22dbc07b238..e94fe2c3b67 100644 --- a/doc/src/sgml/ref/create_table.sgml +++ b/doc/src/sgml/ref/create_table.sgml @@ -1385,7 +1385,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM </varlistentry> <varlistentry> - <term><literal>autovacuum_vacuum_cost_delay</literal>, <literal>toast.autovacuum_vacuum_cost_delay</literal> (<type>integer</type>)</term> + <term><literal>autovacuum_vacuum_cost_delay</literal>, <literal>toast.autovacuum_vacuum_cost_delay</literal> (<type>floating point</type>)</term> <listitem> <para> Per-table value for <xref linkend="guc-autovacuum-vacuum-cost-delay"/> |