diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index e9bf121f542..bd20e14ea57 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -785,6 +785,8 @@ PostmasterMain(int argc, char *argv[])
 	if (!SelectConfigFiles(userDoption, progname))
 		ExitPostmaster(2);
 
+	set_default_effective_cache_size();
+
 	if (output_config_variable != NULL)
 	{
 		/*
@@ -795,8 +797,6 @@ PostmasterMain(int argc, char *argv[])
 		ExitPostmaster(0);
 	}
 
-	set_default_effective_cache_size();
-
 	/* Verify that DataDir looks reasonable */
 	checkDataDir();
 
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 1eaf287eec9..4b2a7761af8 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -3592,6 +3592,8 @@ PostgresMain(int argc, char *argv[],
 			proc_exit(1);
 	}
 
+	set_default_effective_cache_size();
+	    
 	/*
 	 * You might expect to see a setsid() call here, but it's not needed,
 	 * because if we are under a postmaster then BackendInitialize() did it.