diff --git a/src/calibre/utils/ipc/simple_worker.py b/src/calibre/utils/ipc/simple_worker.py
index 8454986360..4eec56994a 100644
--- a/src/calibre/utils/ipc/simple_worker.py
+++ b/src/calibre/utils/ipc/simple_worker.py
@@ -62,16 +62,18 @@ class ConnectedWorker(Thread):
             except:
                 self.tb = traceback.format_exc()
 
-def communicate(ans, worker, listener, args, timeout=300):
+def communicate(ans, worker, listener, args, timeout=300, heartbeat=None):
     cw = ConnectedWorker(listener, args)
     cw.start()
     st = time.time()
+    check_heartbeat = callable(heartbeat)
     while worker.is_alive and cw.is_alive():
         cw.join(0.01)
         delta = time.time() - st
         if not cw.accepted and delta > min(10, timeout):
             break
-        if delta > timeout:
+        hung = not heartbeat() if check_heartbeat else delta > timeout
+        if hung:
             raise WorkerError('Worker appears to have hung')
     if not cw.accepted:
         if not cw.tb:
@@ -85,7 +87,7 @@ def communicate(ans, worker, listener, args, timeout=300):
     ans['result'] = cw.res['result']
 
 def fork_job(mod_name, func_name, args=(), kwargs={}, timeout=300, # seconds
-        cwd=None, priority='normal', env={}, no_output=False):
+        cwd=None, priority='normal', env={}, no_output=False, heartbeat=None):
 
     ans = {'result':None, 'stdout_stderr':None}
 
@@ -108,7 +110,7 @@ def fork_job(mod_name, func_name, args=(), kwargs={}, timeout=300, # seconds
     w(cwd=cwd, priority=priority)
     try:
         communicate(ans, w, listener, (mod_name, func_name, args, kwargs),
-                timeout=timeout)
+                timeout=timeout, heartbeat=heartbeat)
     finally:
         t = Thread(target=w.kill)
         t.daemon=True