diff --git a/artiq/master/scheduler.py b/artiq/master/scheduler.py
index e21fcda73..d1c19396a 100644
--- a/artiq/master/scheduler.py
+++ b/artiq/master/scheduler.py
@@ -69,6 +69,7 @@ class Scheduler:
             try:
                 yield from worker.run()
                 yield from worker.analyze()
+                yield from worker.write_results()
             finally:
                 yield from worker.close()
         except Exception as e:
diff --git a/artiq/master/worker.py b/artiq/master/worker.py
index 45cd3d58e..1ddc63307 100644
--- a/artiq/master/worker.py
+++ b/artiq/master/worker.py
@@ -23,15 +23,20 @@ class WorkerError(Exception):
 
 class Worker:
     def __init__(self, handlers,
-                 send_timeout=0.5, prepare_timeout=15.0, term_timeout=1.0):
+                 send_timeout=0.5, term_timeout=1.0,
+                 prepare_timeout=15.0, results_timeout=15.0):
         self.handlers = handlers
         self.send_timeout = send_timeout
-        self.prepare_timeout = prepare_timeout
         self.term_timeout = term_timeout
+        self.prepare_timeout = prepare_timeout
+        self.results_timeout = results_timeout
         self.watchdogs = dict()  # wid -> expiration (using time.monotonic)
 
     def create_watchdog(self, t):
-        avail = set(range(len(self.watchdogs) + 1)) \
+        n_user_watchdogs = len(self.watchdogs)
+        if -1 in self.watchdogs:
+            n_user_watchdogs -= 1
+        avail = set(range(n_user_watchdogs + 1)) \
             - set(self.watchdogs.keys())
         wid = next(iter(avail))
         self.watchdogs[wid] = time.monotonic() + strip_unit(t, "s")
@@ -101,9 +106,12 @@ class Worker:
         return obj
 
     @asyncio.coroutine
-    def _handle_worker_requests(self, timeout_func):
+    def _handle_worker_requests(self):
         while True:
-            obj = yield from self._recv(timeout_func())
+            try:
+                obj = yield from self._recv(self.watchdog_time())
+            except WorkerTimeout:
+                raise WorkerWatchdogTimeout
             action = obj["action"]
             if action == "completed":
                 return
@@ -122,32 +130,40 @@ class Worker:
                          "message": traceback.format_exc()}
             yield from self._send(reply, self.send_timeout)
 
+    @asyncio.coroutine
+    def _worker_action(self, obj, timeout=None):
+        if timeout is not None:
+            self.watchdogs[-1] = time.monotonic() + timeout
+        try:
+            yield from self._send(obj, self.send_timeout)
+            try:
+                yield from self._handle_worker_requests()
+            except WorkerTimeout:
+                raise WorkerWatchdogTimeout
+        finally:
+            if timeout is not None:
+                del self.watchdogs[-1]
+
     @asyncio.coroutine
     def prepare(self, rid, run_params):
         yield from self._create_process()
         try:
-            obj = {"action": "prepare", "rid": rid, "run_params": run_params}
-            yield from self._send(obj, self.send_timeout)
-            end_time = time.monotonic() + self.prepare_timeout
-            yield from self._handle_worker_requests(
-                lambda: end_time - time.monotonic())
+            yield from self._worker_action(
+                {"action": "prepare", "rid": rid, "run_params": run_params},
+                self.prepare_timeout)
         except:
             yield from self.close()
             raise
 
-    @asyncio.coroutine
-    def _run_analyze(self, action):
-        obj = {"action": action}
-        yield from self._send(obj, self.send_timeout)
-        try:
-            yield from self._handle_worker_requests(self.watchdog_time)
-        except WorkerTimeout:
-            raise WorkerWatchdogTimeout
-
     @asyncio.coroutine
     def run(self):
-        yield from self._run_analyze("run")
+        yield from self._worker_action({"action": "run"})
 
     @asyncio.coroutine
     def analyze(self):
-        yield from self._run_analyze("analyze")
+        yield from self._worker_action({"action": "analyze"})
+
+    @asyncio.coroutine
+    def write_results(self):
+        yield from self._worker_action({"action": "write_results"},
+                                       self.results_timeout)
diff --git a/artiq/master/worker_impl.py b/artiq/master/worker_impl.py
index 49ad8c132..f428093a4 100644
--- a/artiq/master/worker_impl.py
+++ b/artiq/master/worker_impl.py
@@ -118,6 +118,8 @@ def main():
                 put_object({"action": "completed"})
             elif action == "analyze":
                 exp_inst.analyze()
+                put_object({"action": "completed"})
+            elif action == "write_results":
                 f = get_hdf5_output(start_time, rid, exp.__name__)
                 try:
                     rdb.write_hdf5(f)