From 45d63168ddeb8bdf3ed29ca150f453ffcd051697 Mon Sep 17 00:00:00 2001
From: Andres Freund <andres@anarazel.de>
Date: Sun, 20 Feb 2022 12:20:42 -0800
Subject: [PATCH v1 1/5] Set default_toast_compression=lz4 if available.

Makes initdb faster, generally a good idea, users shouldn't have to bother
with this.

Author: Justin Pryzby <pryzbyj@telsasoft.com>
Discussion: https://postgr.es/m/20220216212952.GH31460@telsasoft.com
---
 src/backend/utils/misc/guc.c | 4 ++++
 src/bin/initdb/initdb.c      | 6 ++++++
 doc/src/sgml/config.sgml     | 4 +++-
 3 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 01f373815e0..f502f9840f5 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -4727,7 +4727,11 @@ static struct config_enum ConfigureNamesEnum[] =
 			NULL
 		},
 		&default_toast_compression,
+#ifdef USE_LZ4
+		TOAST_LZ4_COMPRESSION,
+#else
 		TOAST_PGLZ_COMPRESSION,
+#endif
 		default_toast_compression_options,
 		NULL, NULL, NULL
 	},
diff --git a/src/bin/initdb/initdb.c b/src/bin/initdb/initdb.c
index 97f15971e2b..73ccbf63207 100644
--- a/src/bin/initdb/initdb.c
+++ b/src/bin/initdb/initdb.c
@@ -1185,6 +1185,12 @@ setup_config(void)
 							  "#update_process_title = off");
 #endif
 
+#ifdef USE_LZ4
+	conflines = replace_token(conflines,
+							  "#default_toast_compression = 'pglz'",
+							  "#default_toast_compression = 'lz4'");
+#endif
+
 	/*
 	 * Change password_encryption setting to md5 if md5 was chosen as an
 	 * authentication method, unless scram-sha-256 was also chosen.
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index d99bf38e677..97e78506b13 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -8536,7 +8536,9 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv;
         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>.
+        The default is <literal>lz4</literal> if available at the time 
+        <productname>PostgreSQL</productname> was compiled, otherwise
+        <literal>pglz</literal>.
        </para>
       </listitem>
      </varlistentry>
-- 
2.34.0