diff --git a/examples/wifi/iperf/components/iperf/iperf.c b/examples/wifi/iperf/components/iperf/iperf.c
index 71d09fee..7fd0e57d 100644
--- a/examples/wifi/iperf/components/iperf/iperf.c
+++ b/examples/wifi/iperf/components/iperf/iperf.c
@@ -18,7 +18,7 @@
 typedef struct {
     iperf_cfg_t cfg;
     bool finish;
-    uint32_t total_len;
+    uint64_t total_len;
     uint32_t buffer_len;
     uint8_t *buffer;
     uint32_t sockfd;
diff --git a/examples/wifi/iperf/sdkconfig.defaults b/examples/wifi/iperf/sdkconfig.defaults
index 82a089fc..e3734314 100644
--- a/examples/wifi/iperf/sdkconfig.defaults
+++ b/examples/wifi/iperf/sdkconfig.defaults
@@ -7,3 +7,4 @@ CONFIG_LWIP_TCP_SND_BUF_DEFAULT=11680
 CONFIG_LWIP_TCP_WND_DEFAULT=7300
 CONFIG_LWIP_TCP_MSS=1460
 CONFIG_LWIP_TCP_RECVMBOX_SIZE=7
+CONFIG_NEWLIB_NANO_FORMAT=n