postgres.git / summary / log / commit / refs
commit 7c1849311e49ec57cb86b32a9aa630456588c3f0
Author: Michael Paquier <michael@paquier.xyz>
Date: Wed Mar 04 04:05:31 2026 +0000
Reverted by: 4f0b3afab4da
Change default value of default_toast_compression to "lz4", when available
The default value for default_toast_compression was "pglz". The main
reason for this choice is that this option is always available, pglz
code being embedded in Postgres. However, it is known that LZ4 is more
efficient than pglz: less CPU required, more compression on average. As
of this commit, the default value of default_toast_compression becomes
"lz4", if available. By switching to LZ4 as the default, users should
see natural speedups on TOAST data reads and/or writes.
Support for LZ4 in TOAST compression was added in Postgres v14, or 5
releases ago. This should be long enough to consider this feature as
stable.
--with-lz4 is removed, replaced by a --without-lz4 to disable LZ4 in the
builds on an option-basis, following a practice similar to readline or
ICU. References to --with-lz4 are removed from the documentation.
While at it, quotes are removed from default_toast_compression in
postgresql.conf.sample. Quotes are not required in this case. The
in-place value replacement done by initdb if the build supports LZ4
would not use them in the postgresql.conf file added to a
freshly-initialized cluster.
For the reference, a similar switch has been done with ICU in
fcb21b3acdcb. Some of the changes done in this commit are consistent
with that.
Note: this is going to create some disturbance in the buildfarm, in
environments where lz4 is not installed.
Author: Euler Taveira <euler@eulerto.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Aleksander Alekseev <aleksander@tigerdata.com>
Discussion: https://posgr.es/m/435df33a-129e-4f0c-a803-f3935c5a5ecb@eisentraut.org
.cirrus.tasks.yml | 1 +
configure | 6 ++++--
configure.ac | 2 +-
doc/src/sgml/config.sgml | 13 ++++++-------
doc/src/sgml/installation.sgml | 21 ++++++++++++---------
doc/src/sgml/ref/alter_table.sgml | 4 +---
doc/src/sgml/ref/create_table.sgml | 4 +---
doc/src/sgml/ref/pg_receivewal.sgml | 4 +---
src/backend/access/common/toast_compression.c | 2 +-
src/backend/utils/misc/guc_parameters.dat | 2 +-
src/backend/utils/misc/postgresql.conf.sample | 2 +-
src/bin/initdb/initdb.c | 5 +++++
src/include/access/toast_compression.h | 9 +++++++++
13 files changed, 44 insertions(+), 31 deletions(-)
diff --git a/.cirrus.tasks.yml b/.cirrus.tasks.yml
index 4841a204248..a3107f82730 100644
--- a/.cirrus.tasks.yml
+++ b/.cirrus.tasks.yml
@@ -984,6 +984,7 @@ task:
--host=x86_64-w64-mingw32ucrt \
--enable-cassert \
--without-icu \
+ --without-lz4 \
CC="ccache x86_64-w64-mingw32ucrt-gcc" \
CXX="ccache x86_64-w64-mingw32ucrt-g++"
make -s -j${BUILD_JOBS} clean
diff --git a/configure b/configure
index b30b98a586e..7afd8ba01e8 100755
--- a/configure
+++ b/configure
@@ -1603,7 +1603,7 @@ Optional Packages:
--with-system-tzdata=DIR
use system time zone data in DIR
--without-zlib do not use Zlib
- --with-lz4 build with LZ4 support
+ --without-lz4 build without LZ4 support
--with-zstd build with ZSTD support
--with-ssl=LIB use LIB for SSL/TLS support (openssl)
--with-openssl obsolete spelling of --with-ssl=openssl
@@ -9570,7 +9570,9 @@ $as_echo "#define USE_LZ4 1" >>confdefs.h
esac
else
- with_lz4=no
+ with_lz4=yes
+
+$as_echo "#define USE_LZ4 1" >>confdefs.h
fi
diff --git a/configure.ac b/configure.ac
index f4e3bd307c8..60d1c1900f2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1188,7 +1188,7 @@ AC_SUBST(with_zlib)
# LZ4
#
AC_MSG_CHECKING([whether to build with LZ4 support])
-PGAC_ARG_BOOL(with, lz4, no, [build with LZ4 support],
+PGAC_ARG_BOOL(with, lz4, yes, [build without LZ4 support],
[AC_DEFINE([USE_LZ4], 1, [Define to 1 to build with LZ4 support. (--with-lz4)])])
AC_MSG_RESULT([$with_lz4])
AC_SUBST(with_lz4)
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index f670e2d4c31..6779bc844d0 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -3498,10 +3498,9 @@ include_dir 'conf.d'
etc.).
A compressed page image will be decompressed during WAL replay.
The supported methods are <literal>pglz</literal>,
- <literal>lz4</literal> (if <productname>PostgreSQL</productname>
- was compiled with <option>--with-lz4</option>) and
- <literal>zstd</literal> (if <productname>PostgreSQL</productname>
- was compiled with <option>--with-zstd</option>).
+ <literal>lz4</literal> and <literal>zstd</literal> (if
+ <productname>PostgreSQL</productname> was compiled with
+ <option>--with-zstd</option>).
The default value is <literal>off</literal>.
Only superusers and users with the appropriate <literal>SET</literal>
privilege can change this setting.
@@ -10018,9 +10017,9 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
<command>CREATE TABLE</command> or
<command>ALTER TABLE</command>.)
The supported compression methods are <literal>pglz</literal> and
- (if <productname>PostgreSQL</productname> was compiled with
- <option>--with-lz4</option>) <literal>lz4</literal>.
- The default is <literal>pglz</literal>.
+ <literal>lz4</literal>.
+ The default is <literal>lz4</literal> (if available); otherwise,
+ <literal>pglz</literal>.
</para>
</listitem>
</varlistentry>
diff --git a/doc/src/sgml/installation.sgml b/doc/src/sgml/installation.sgml
index b345a105674..a026ffea68d 100644
--- a/doc/src/sgml/installation.sgml
+++ b/doc/src/sgml/installation.sgml
@@ -975,15 +975,6 @@ build-postgresql:
</listitem>
</varlistentry>
- <varlistentry id="configure-option-with-lz4">
- <term><option>--with-lz4</option></term>
- <listitem>
- <para>
- Build with <productname>LZ4</productname> compression support.
- </para>
- </listitem>
- </varlistentry>
-
<varlistentry id="configure-option-with-zstd">
<term><option>--with-zstd</option></term>
<listitem>
@@ -1315,6 +1306,18 @@ build-postgresql:
</listitem>
</varlistentry>
+ <varlistentry id="configure-option-without-lz4">
+ <term><option>--without-lz4</option></term>
+ <listitem>
+ <para>
+ <indexterm>
+ <primary>lz4</primary>
+ </indexterm>
+ Prevents use of the <application>LZ4</application> library.
+ </para>
+ </listitem>
+ </varlistentry>
+
</variablelist>
</sect3>
diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml
index aab2c6eb19f..9d2c87b660a 100644
--- a/doc/src/sgml/ref/alter_table.sgml
+++ b/doc/src/sgml/ref/alter_table.sgml
@@ -462,9 +462,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
its existing compression method, rather than being recompressed with the
compression method of the target column.
The supported compression
- methods are <literal>pglz</literal> and <literal>lz4</literal>.
- (<literal>lz4</literal> is available only if <option>--with-lz4</option>
- was used when building <productname>PostgreSQL</productname>.) In
+ methods are <literal>pglz</literal> and <literal>lz4</literal>. In
addition, <replaceable class="parameter">compression_method</replaceable>
can be <literal>default</literal>, which selects the default behavior of
consulting the <xref linkend="guc-default-toast-compression"/> setting
diff --git a/doc/src/sgml/ref/create_table.sgml b/doc/src/sgml/ref/create_table.sgml
index 982532fe725..188bc11e940 100644
--- a/doc/src/sgml/ref/create_table.sgml
+++ b/doc/src/sgml/ref/create_table.sgml
@@ -344,9 +344,7 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
has no direct effect, because such tables have no storage of their own,
but the configured value will be inherited by newly-created partitions.
The supported compression methods are <literal>pglz</literal> and
- <literal>lz4</literal>. (<literal>lz4</literal> is available only if
- <option>--with-lz4</option> was used when building
- <productname>PostgreSQL</productname>.) In addition,
+ <literal>lz4</literal>. In addition,
<replaceable class="parameter">compression_method</replaceable>
can be <literal>default</literal> to explicitly specify the default
behavior, which is to consult the
diff --git a/doc/src/sgml/ref/pg_receivewal.sgml b/doc/src/sgml/ref/pg_receivewal.sgml
index 9e353a068e5..1896f4da0e8 100644
--- a/doc/src/sgml/ref/pg_receivewal.sgml
+++ b/doc/src/sgml/ref/pg_receivewal.sgml
@@ -275,9 +275,7 @@ PostgreSQL documentation
</para>
<para>
The compression method can be set to <literal>gzip</literal>,
- <literal>lz4</literal> (if <productname>PostgreSQL</productname>
- was compiled with <option>--with-lz4</option>) or
- <literal>none</literal> for no compression.
+ <literal>lz4</literal> or <literal>none</literal> for no compression.
A compression detail string can optionally be specified. If the
detail string is an integer, it specifies the compression level.
Otherwise, it should be a comma-separated list of items, each of the
diff --git a/src/backend/access/common/toast_compression.c b/src/backend/access/common/toast_compression.c
index 4d00537049e..5a5d579494a 100644
--- a/src/backend/access/common/toast_compression.c
+++ b/src/backend/access/common/toast_compression.c
@@ -23,7 +23,7 @@
#include "varatt.h"
/* GUC */
-int default_toast_compression = TOAST_PGLZ_COMPRESSION;
+int default_toast_compression = DEFAULT_TOAST_COMPRESSION;
#define NO_COMPRESSION_SUPPORT(method) \
ereport(ERROR, \
diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat
index 9507778415d..5ee84a639d8 100644
--- a/src/backend/utils/misc/guc_parameters.dat
+++ b/src/backend/utils/misc/guc_parameters.dat
@@ -735,7 +735,7 @@
{ name => 'default_toast_compression', type => 'enum', context => 'PGC_USERSET', group => 'CLIENT_CONN_STATEMENT',
short_desc => 'Sets the default compression method for compressible values.',
variable => 'default_toast_compression',
- boot_val => 'TOAST_PGLZ_COMPRESSION',
+ boot_val => 'DEFAULT_TOAST_COMPRESSION',
options => 'default_toast_compression_options',
},
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index f938cc65a3a..e686d88afc4 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -779,7 +779,7 @@
#row_security = on
#default_table_access_method = 'heap'
#default_tablespace = '' # a tablespace name, '' uses the default
-#default_toast_compression = 'pglz' # 'pglz' or 'lz4'
+#default_toast_compression = pglz # pglz or lz4
#temp_tablespaces = '' # a list of tablespace names, '' uses
# only default tablespace
#check_function_bodies = on
diff --git a/src/bin/initdb/initdb.c b/src/bin/initdb/initdb.c
index 53ec1544ff3..6387c66289e 100644
--- a/src/bin/initdb/initdb.c
+++ b/src/bin/initdb/initdb.c
@@ -1426,6 +1426,11 @@ setup_config(void)
"0640", false);
}
+#if USE_LZ4
+ conflines = replace_guc_value(conflines, "default_toast_compression",
+ "lz4", true);
+#endif
+
/*
* Now replace anything that's overridden via -c switches.
*/
diff --git a/src/include/access/toast_compression.h b/src/include/access/toast_compression.h
index 5f3ffa9ab2d..3265f10b734 100644
--- a/src/include/access/toast_compression.h
+++ b/src/include/access/toast_compression.h
@@ -52,6 +52,15 @@ typedef enum ToastCompressionId
#define CompressionMethodIsValid(cm) ((cm) != InvalidCompressionMethod)
+/*
+ * Choose an appropriate default toast compression method. If lz4 is
+ * compiled-in, use it, otherwise use pglz.
+ */
+#ifdef USE_LZ4
+#define DEFAULT_TOAST_COMPRESSION TOAST_LZ4_COMPRESSION
+#else
+#define DEFAULT_TOAST_COMPRESSION TOAST_PGLZ_COMPRESSION
+#endif
/* pglz compression/decompression routines */
extern varlena *pglz_compress_datum(const varlena *value);
[parent: 1f4f87d79436]