Use override=True for config1 in adjust_config_by_multi_process_divid…

…er()

Sometimes, those configurations are provided through commandline. In general,
configurations provided through commandline will not be changed by config1().
However, for DDP training, even if these configurations are from commandline,
we still need to change them.

alf/config_helpers.py

@@ -154,7 +154,7 @@ def adjust_config_by_multi_process_divider(ddp_rank: int,
         tag,
         math.ceil(num_parallel_environments / multi_process_divider),
         raise_if_used=False,
-        override_sole_init=True)
+        override_all=True)
 
     # Adjust the mini_batch_size. If the original configured value is 64 and
     # there are 4 processes, it should mean that "jointly the 4 processes have
@@ -167,7 +167,7 @@ def adjust_config_by_multi_process_divider(ddp_rank: int,
             tag,
             math.ceil(mini_batch_size / multi_process_divider),
             raise_if_used=False,
-            override_sole_init=True)
+            override_all=True)
 
     # If the termination condition is num_env_steps instead of num_iterations,
     # we need to adjust it as well since each process only sees env steps taking
@@ -179,15 +179,15 @@ def adjust_config_by_multi_process_divider(ddp_rank: int,
             tag,
             math.ceil(num_env_steps / multi_process_divider),
             raise_if_used=False,
-            override_sole_init=True)
+            override_all=True)
 
     tag = 'TrainerConfig.initial_collect_steps'
     init_collect_steps = get_config_value(tag)
     config1(
         tag,
         math.ceil(init_collect_steps / multi_process_divider),
         raise_if_used=False,
-        override_sole_init=True)
+        override_all=True)
 
     # Only allow process with rank 0 to have evaluate. Enabling evaluation for
     # other parallel processes is a waste as such evaluation does not offer more
@@ -197,7 +197,7 @@ def adjust_config_by_multi_process_divider(ddp_rank: int,
             'TrainerConfig.evaluate',
             False,
             raise_if_used=False,
-            override_sole_init=True)
+            override_all=True)
 
 
 def parse_config(conf_file, conf_params, create_env=True):

alf/config_util.py

@@ -366,7 +366,8 @@ def config1(config_name,
             mutable=True,
             raise_if_used=True,
             sole_init=False,
-            override_sole_init=False):
+            override_sole_init=False,
+            override_all=False):
     """Set one configurable value.
 
     Args:
@@ -391,15 +392,33 @@ def config1(config_name,
             where the student must override certain configs inherited from the
             teacher). If the config is immutable, a warning will be declared with
             no changes made.
-    """
+        override_all (bool): If True, the value of the config will be set regardless
+            of any pre-existing ``mutable`` or ``sole_init`` settings. This should
+            be used only when absolutely necessary (e.g., adjusting certain configs
+            such as mini_batch_size for DDP workers.)."""
     config_node = _get_config_node(config_name)
 
     if raise_if_used and config_node.is_used():
         raise ValueError(
             "Config '%s' has already been used. You should config "
             "its value before using it." % config_name)
 
-    if override_sole_init:
+    if override_all:
+        if config_node.get_sole_init():
+            logging.warning(
+                "The value of config '%s' (%s) is protected by sole_init. "
+                "It is now being overridden by the overide_all flag to a new value %s. "
+                "Use at your own risk." % (config_name,
+                                           config_node.get_value(), value))
+        if not config_node.is_mutable():
+            logging.warning(
+                "The value of config '%s' (%s) is immutable. "
+                "It is now being overridden by the overide_all flag to a new value %s. "
+                "Use at your own risk." % (config_name,
+                                           config_node.get_value(), value))
+        config_node.set_value(value)
+        return
+    elif override_sole_init:
         if config_node.is_configured():
             if not config_node.is_mutable():
                 logging.warning(