diff --git a/tpool/tpool_generic.cc b/tpool/tpool_generic.cc
index b17f1d5480a..c9b69147792 100644
--- a/tpool/tpool_generic.cc
+++ b/tpool/tpool_generic.cc
@@ -393,7 +393,9 @@ public:
     */
     void set_period(int period_ms)
     {
-      std::unique_lock<std::mutex> lk(m_mtx);
+      std::unique_lock<std::mutex> lk(m_mtx, std::defer_lock);
+      if (!lk.try_lock())
+        return;
       if (!m_on)
         return;
       if (!m_pool)