diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/config.sgml | 16 | ||||
| -rw-r--r-- | doc/src/sgml/func.sgml | 11 |
2 files changed, 22 insertions, 5 deletions
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index b14c5d81a15..3dec0b7cfeb 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -4318,11 +4318,17 @@ restore_command = 'copy "C:\\server\\archivedir\\%f" "%p"' # Windows <listitem> <para> Enables the WAL summarizer process. Note that WAL summarization can - be enabled either on a primary or on a standby. WAL summarization - cannot be enabled when <varname>wal_level</varname> is set to - <literal>minimal</literal>. This parameter can only be set in the - <filename>postgresql.conf</filename> file or on the server command line. - The default is <literal>off</literal>. + be enabled either on a primary or on a standby. This parameter can only + be set in the <filename>postgresql.conf</filename> file or on the server + command line. The default is <literal>off</literal>. + </para> + <para> + The server cannot be started with <literal>summarize_wal=on</literal> + if <literal>wal_level</literal> is set to <literal>minimal</literal>. If + <literal>summarize_wal=on</literal> is configured after server startup + while <literal>wal_level=minimal</literal>, the summarizer will run + but refuse to generate summary files for any WAL generated with + <literal>wal_level=minimal</literal>. </para> </listitem> </varlistentry> diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml index 3f93c61aa3c..fd5699f4d85 100644 --- a/doc/src/sgml/func.sgml +++ b/doc/src/sgml/func.sgml @@ -28001,6 +28001,17 @@ acl | {postgres=arwdDxtm/postgres,foo=r/postgres} not running, it will be equal to <literal>summarized_lsn</literal>. <literal>summarizer_pid</literal> is the PID of the WAL summarizer process, if it is running, and otherwise NULL. + </para> + <para> + As a special exception, the WAL summarizer will refuse to generate + WAL summary files if run on WAL generated under + <literal>wal_level=minimal</literal>, since such summaries would be + unsafe to use as the basis for an incremental backup. In this case, + the fields above will continue to advance as if summaries were being + generated, but nothing will be written to disk. Once the summarizer + reaches WAL generated while <literal>wal_level</literal> was set + to <literal>replica</literal> or higher, it will resume writing + summaries to disk. </para></entry> </row> </tbody> |