Improve defaults shown in postgresql.conf.sample and pg_settings

bmomjian · bmomjian · commit f7bda63a487c · 2021-08-23T12:33:38.000-04:00
Previously, these showed unlikely default values. The new default value 128MB (since PG 10) is not always accurate since initdb tries several increasing values, but it likely to be accurate. Reported-by: Zhangjie <zhangjie2@fujitsu.com> Discussion: https://postgr.es/m/TYWPR01MB7678772FD8640C404F1DC882F9079@TYWPR01MB7678.jpnprd01.prod.outlook.com Author: Zhangjie Backpatch-through: master
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
@@ -2333,7 +2333,7 @@ static struct config_int ConfigureNamesInt[] =
 			GUC_UNIT_BLOCKS
 		},
 		&NBuffers,
-		1024, 16, INT_MAX / 2,
+		16384, 16, INT_MAX / 2,
 		NULL, NULL, NULL
 	},
 
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
@@ -124,7 +124,7 @@
 
 # - Memory -
 
-#shared_buffers = 32MB			# min 128kB
+#shared_buffers = 128MB			# min 128kB
 					# (change requires restart)
 #huge_pages = try			# on, off, or try
 					# (change requires restart)
diff --git a/src/bin/initdb/initdb.c b/src/bin/initdb/initdb.c
@@ -1071,7 +1071,7 @@ setup_config(void)
 	else
 		snprintf(repltok, sizeof(repltok), "shared_buffers = %dkB",
 				 n_buffers * (BLCKSZ / 1024));
-	conflines = replace_token(conflines, "#shared_buffers = 32MB", repltok);
+	conflines = replace_token(conflines, "#shared_buffers = 128MB", repltok);
 
 #ifdef HAVE_UNIX_SOCKETS
 	snprintf(repltok, sizeof(repltok), "#unix_socket_directories = '%s'",
