diff options
| author | Robert Haas | 2022-03-30 13:35:14 +0000 |
|---|---|---|
| committer | Robert Haas | 2022-03-30 13:41:26 +0000 |
| commit | 51c0d186d99a18e6aae53003f5138f20991e15a6 (patch) | |
| tree | 0c37c8899e6448c1bd56919741f58e8e5a99c7b5 /doc/src | |
| parent | c6863b85829149e2241faafa161b6c5af1f06cb9 (diff) | |
Allow parallel zstd compression when taking a base backup.
libzstd allows transparent parallel compression just by setting
an option when creating the compression context, so permit that
for both client and server-side backup compression. To use this,
use something like pg_basebackup --compress WHERE-zstd:workers=N
where WHERE is "client" or "server" and N is an integer.
When compression is performed on the server side, this will spawn
threads inside the PostgreSQL backend. While there is almost no
PostgreSQL server code which is thread-safe, the threads here are used
internally by libzstd and touch only data structures controlled by
libzstd.
Patch by me, based in part on earlier work by Dipesh Pandit
and Jeevan Ladhe. Reviewed by Justin Pryzby.
Discussion: http://postgr.es/m/CA+Tgmobj6u-nWF-j=FemygUhobhryLxf9h-wJN7W-2rSsseHNA@mail.gmail.com
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/protocol.sgml | 12 | ||||
| -rw-r--r-- | doc/src/sgml/ref/pg_basebackup.sgml | 4 |
2 files changed, 11 insertions, 5 deletions
diff --git a/doc/src/sgml/protocol.sgml b/doc/src/sgml/protocol.sgml index 2fa3cedfe9e..98f0bc3cc34 100644 --- a/doc/src/sgml/protocol.sgml +++ b/doc/src/sgml/protocol.sgml @@ -2739,17 +2739,23 @@ The commands accepted in replication mode are: option. If the value is an integer, it specifies the compression level. Otherwise, it should be a comma-separated list of items, each of the form <literal>keyword</literal> or - <literal>keyword=value</literal>. Currently, the only supported - keyword is <literal>level</literal>, which sets the compression - level. + <literal>keyword=value</literal>. Currently, the supported keywords + are <literal>level</literal> and <literal>workers</literal>. </para> <para> + The <literal>level</literal> keyword sets the compression level. For <literal>gzip</literal> the compression level should be an integer between 1 and 9, for <literal>lz4</literal> an integer between 1 and 12, and for <literal>zstd</literal> an integer between 1 and 22. </para> + + <para> + The <literal>workers</literal> keyword sets the number of threads + that should be used for parallel compression. Parallel compression + is supported only for <literal>zstd</literal>. + </para> </listitem> </varlistentry> diff --git a/doc/src/sgml/ref/pg_basebackup.sgml b/doc/src/sgml/ref/pg_basebackup.sgml index d9233beb8e1..82f5f606250 100644 --- a/doc/src/sgml/ref/pg_basebackup.sgml +++ b/doc/src/sgml/ref/pg_basebackup.sgml @@ -424,8 +424,8 @@ PostgreSQL documentation integer, it specifies the compression level. Otherwise, it should be a comma-separated list of items, each of the form <literal>keyword</literal> or <literal>keyword=value</literal>. - Currently, the only supported keyword is <literal>level</literal>, - which sets the compression level. + Currently, the supported keywords are <literal>level</literal> + and <literal>workers</literal>. </para> <para> If no compression level is specified, the default compression level |