diff --git a/src/backend/catalog/Catalog.pm b/src/backend/catalog/Catalog.pm
index e91a8e10a8..a71f5b05a8 100644
--- a/src/backend/catalog/Catalog.pm
+++ b/src/backend/catalog/Catalog.pm
@@ -287,6 +287,8 @@ sub ParseData
 	my $catname = $1;
 	my $data    = [];
 
+	if ($preserve_formatting)
+	{
 	# Scan the input file.
 	while (<$ifd>)
 	{
@@ -346,11 +348,25 @@ sub ParseData
 		{
 			push @$data, $hash_ref if !$hash_ref->{autogenerated};
 		}
-		elsif ($preserve_formatting)
+		else
 		{
 			push @$data, $_;
 		}
 	}
+	}
+	else
+	{
+		# When we only care about the contents, it's faster to read and eval
+		# the whole file at once.
+		local $/;
+		my $full_file = <$ifd>;
+		eval '$data = ' . $full_file;    ## no critic (ProhibitStringyEval)
+		foreach my $hash_ref (@{$data})
+		{
+			AddDefaultValues($hash_ref, $schema, $catname);
+		}
+	}
+
 	close $ifd;
 
 	# If this is pg_type, auto-generate array types too.