diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/catalogs.sgml | 38 | ||||
| -rw-r--r-- | doc/src/sgml/config.sgml | 23 | ||||
| -rw-r--r-- | doc/src/sgml/high-availability.sgml | 8 |
3 files changed, 66 insertions, 3 deletions
diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml index 64614b569c8..0d61d98b115 100644 --- a/doc/src/sgml/catalogs.sgml +++ b/doc/src/sgml/catalogs.sgml @@ -9907,6 +9907,44 @@ SELECT * FROM pg_locks pl LEFT JOIN pg_prepared_xacts ppx </entry> </row> + <row> + <entry><structfield>wal_status</structfield></entry> + <entry><type>text</type></entry> + <entry></entry> + + <entry>Availability of WAL files claimed by this slot. + Possible values are: + <simplelist> + <member> + <literal>normal</literal> means that the claimed files + are within <varname>max_wal_size</varname> + </member> + <member> + <literal>reserved</literal> means that <varname>max_wal_size</varname> + is exceeded but the files are still held, either by some replication + slot or by <varname>wal_keep_segments</varname> + </member> + <member> + <literal>lost</literal> means that some WAL files are definitely lost + and this slot cannot be used to resume replication anymore. + </member> + </simplelist> + The last two states are seen only when + <xref linkend="guc-max-slot-wal-keep-size"/> is + non-negative. If <structfield>restart_lsn</structfield> is NULL, this + field is null. + </entry> + </row> + + <row> + <entry><structfield>min_safe_lsn</structfield></entry> + <entry><type>pg_lsn</type></entry> + <entry></entry> + <entry> + The minimum LSN currently available for walsenders. + </entry> + </row> + </tbody> </tgroup> </table> diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index f68c9922136..095b3668b85 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -3777,6 +3777,29 @@ restore_command = 'copy "C:\\server\\archivedir\\%f" "%p"' # Windows </listitem> </varlistentry> + <varlistentry id="guc-max-slot-wal-keep-size" xreflabel="max_slot_wal_keep_size"> + <term><varname>max_slot_wal_keep_size</varname> (<type>integer</type>) + <indexterm> + <primary><varname>max_slot_wal_keep_size</varname> configuration parameter</primary> + </indexterm> + </term> + <listitem> + <para> + Specify the maximum size of WAL files + that <link linkend="streaming-replication-slots">replication + slots</link> are allowed to retain in the <filename>pg_wal</filename> + directory at checkpoint time. + If <varname>max_slot_wal_keep_size</varname> is -1 (the default), + replication slots retain unlimited amount of WAL files. If + restart_lsn of a replication slot gets behind more than that megabytes + from the current LSN, the standby using the slot may no longer be able + to continue replication due to removal of required WAL files. You + can see the WAL availability of replication slots + in <link linkend="view-pg-replication-slots">pg_replication_slots</link>. + </para> + </listitem> + </varlistentry> + <varlistentry id="guc-wal-sender-timeout" xreflabel="wal_sender_timeout"> <term><varname>wal_sender_timeout</varname> (<type>integer</type>) <indexterm> diff --git a/doc/src/sgml/high-availability.sgml b/doc/src/sgml/high-availability.sgml index bb5d9962ed3..4659b9ef5db 100644 --- a/doc/src/sgml/high-availability.sgml +++ b/doc/src/sgml/high-availability.sgml @@ -925,9 +925,11 @@ primary_conninfo = 'host=192.168.1.50 port=5432 user=foo password=foopass' <xref linkend="guc-archive-command"/>. However, these methods often result in retaining more WAL segments than required, whereas replication slots retain only the number of segments - known to be needed. An advantage of these methods is that they bound - the space requirement for <literal>pg_wal</literal>; there is currently no way - to do this using replication slots. + known to be needed. On the other hand, replication slots can retain so + many WAL segments that they fill up the space allocated + for <literal>pg_wal</literal>; + <xref linkend="guc-max-slot-wal-keep-size"/> limits the size of WAL files + retained by replication slots. </para> <para> Similarly, <xref linkend="guc-hot-standby-feedback"/> |