comments

esphome/components/esp32_ble/queue.h

@@ -46,7 +46,13 @@ template<class T> class Queue {
   }
 
   size_t size() const {
-    return q_.size();  // Atomic read, no lock needed
+    // Lock-free size check. While std::queue::size() is not thread-safe, we intentionally
+    // avoid locking here to prevent blocking the BLE callback thread. The size is only
+    // used to decide whether to drop incoming events when the queue is near capacity.
+    // With a queue limit of 40-64 events and normal processing, dropping events should
+    // be extremely rare. When it does approach capacity, being off by 1-2 events is
+    // acceptable to avoid blocking the BLE stack's time-sensitive callbacks.
+    return q_.size();
   }
 
  protected: