language/environment: support non-stored results

artiq/language/environment.py

@@ -201,13 +201,15 @@ class HasEnvironment:
             raise ValueError("Parameter database not present")
         self.__pdb.set(key, value)
 
-    def set_result(self, key, value, realtime=False):
+    def set_result(self, key, value, realtime=False, store=True):
         """Writes the value of a result.
 
         :param realtime: Marks the result as real-time, making it immediately
             available to clients such as the user interface. Returns a
             ``Notifier`` instance that can be used to modify mutable results
             (such as lists) and synchronize the modifications with the clients.
+        :param store: Defines if the result should be stored permanently,
+            e.g. in HDF5 output. Default is to store.
         """
         if self.__rdb is None:
             raise ValueError("Result database not present")
@@ -217,11 +219,13 @@ class HasEnvironment:
             self.__rdb.rt[key] = value
             notifier = self.__rdb.rt[key]
             notifier.kernel_attr_init = False
+            self.__rdb.set_store(key, store)
             return notifier
         else:
             if key in self.__rdb.rt.read:
                 raise ValueError("Result is already realtime")
             self.__rdb.nrt[key] = value
+            self.__rdb.set_store(key, store)
 
     def get_result(self, key):
         """Retrieves the value of a result.

artiq/master/worker_db.py

@@ -91,6 +91,7 @@ class ResultDB:
     def __init__(self):
         self.rt = Notifier(dict())
         self.nrt = dict()
+        self.store = set()
 
     def get(self, key):
         try:
@@ -98,9 +99,17 @@ class ResultDB:
         except KeyError:
             return self.rt[key].read
 
+    def set_store(self, key, store):
+        if store:
+            self.store.add(key)
+        else:
+            self.store.discard(key)
+
     def write_hdf5(self, f):
-        result_dict_to_hdf5(f, self.rt.read)
-        result_dict_to_hdf5(f, self.nrt)
+        result_dict_to_hdf5(
+            f, {k: v for k, v in self.rt.read.items() if k in self.store})
+        result_dict_to_hdf5(
+            f, {k: v for k, v in self.nrt.items() if k in self.store})
 
 
 def _create_device(desc, dmgr):