diff --git a/target/linux/ath79/tiny/config-default b/target/linux/ath79/tiny/config-default
index 01af54446d..f5a485d083 100644
--- a/target/linux/ath79/tiny/config-default
+++ b/target/linux/ath79/tiny/config-default
@@ -1,3 +1,5 @@
+# CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE is not set
+CONFIG_CC_OPTIMIZE_FOR_SIZE=y
 CONFIG_BLK_MQ_PCI=y
 CONFIG_LEDS_RESET=y
 CONFIG_OF_ADDRESS_PCI=y