diff --git a/src/telemetry/telemetry.c b/src/telemetry/telemetry.c
index fae5898897b..44eefaea8c9 100644
--- a/src/telemetry/telemetry.c
+++ b/src/telemetry/telemetry.c
@@ -177,7 +177,7 @@ get_size(int64 size)
 {
 	StringInfo buf = makeStringInfo();
 
-	appendStringInfo(buf, "%ld", size);
+	appendStringInfo(buf, INT64_FORMAT, size);
 	return buf->data;
 }