diff --git a/invokeai/app/services/session_processor/session_processor_default.py b/invokeai/app/services/session_processor/session_processor_default.py
index 4172e45d17..6b4b84e099 100644
--- a/invokeai/app/services/session_processor/session_processor_default.py
+++ b/invokeai/app/services/session_processor/session_processor_default.py
@@ -52,9 +52,9 @@ class DefaultSessionRunner(SessionRunnerBase):
 
     def start(self, services: InvocationServices, cancel_event: ThreadEvent, profiler: Optional[Profiler] = None):
         """Start the session runner"""
-        self.services = services
-        self.cancel_event = cancel_event
-        self.profiler = profiler
+        self._services = services
+        self._cancel_event = cancel_event
+        self._profiler = profiler
 
     def run(self, queue_item: SessionQueueItem):
         """Run the graph"""
@@ -64,33 +64,33 @@ class DefaultSessionRunner(SessionRunnerBase):
 
         while True:
             invocation = queue_item.session.next()
-            if invocation is None or self.cancel_event.is_set():
+            if invocation is None or self._cancel_event.is_set():
                 break
             self.run_node(invocation, queue_item)
-            if queue_item.session.is_complete() or self.cancel_event.is_set():
+            if queue_item.session.is_complete() or self._cancel_event.is_set():
                 break
 
         self._on_after_run_session(queue_item=queue_item)
 
     def _on_before_run_session(self, queue_item: SessionQueueItem) -> None:
         # If profiling is enabled, start the profiler
-        if self.profiler is not None:
-            self.profiler.start(profile_id=queue_item.session_id)
+        if self._profiler is not None:
+            self._profiler.start(profile_id=queue_item.session_id)
 
         if self.on_before_run_session:
             self.on_before_run_session(queue_item=queue_item)
 
     def _on_after_run_session(self, queue_item: SessionQueueItem) -> None:
         # If we are profiling, stop the profiler and dump the profile & stats
-        if self.profiler is not None:
-            profile_path = self.profiler.stop()
+        if self._profiler is not None:
+            profile_path = self._profiler.stop()
             stats_path = profile_path.with_suffix(".json")
-            self.services.performance_statistics.dump_stats(
+            self._services.performance_statistics.dump_stats(
                 graph_execution_state_id=queue_item.session.id, output_path=stats_path
             )
 
         # Send complete event
-        self.services.events.emit_graph_execution_complete(
+        self._services.events.emit_graph_execution_complete(
             queue_batch_id=queue_item.batch_id,
             queue_item_id=queue_item.item_id,
             queue_id=queue_item.queue_id,
@@ -100,8 +100,8 @@ class DefaultSessionRunner(SessionRunnerBase):
         # We'll get a GESStatsNotFoundError if we try to log stats for an untracked graph, but in the processor
         # we don't care about that - suppress the error.
         with suppress(GESStatsNotFoundError):
-            self.services.performance_statistics.log_stats(queue_item.session.id)
-            self.services.performance_statistics.reset_stats()
+            self._services.performance_statistics.log_stats(queue_item.session.id)
+            self._services.performance_statistics.reset_stats()
 
         if self.on_after_run_session:
             self.on_after_run_session(queue_item)
@@ -109,7 +109,7 @@ class DefaultSessionRunner(SessionRunnerBase):
     def _on_before_run_node(self, invocation: BaseInvocation, queue_item: SessionQueueItem):
         """Run before a node is executed"""
         # Send starting event
-        self.services.events.emit_invocation_started(
+        self._services.events.emit_invocation_started(
             queue_batch_id=queue_item.batch_id,
             queue_item_id=queue_item.item_id,
             queue_id=queue_item.queue_id,
@@ -126,7 +126,7 @@ class DefaultSessionRunner(SessionRunnerBase):
     ):
         """Run after a node is executed"""
         # Send complete event on successful runs
-        self.services.events.emit_invocation_complete(
+        self._services.events.emit_invocation_complete(
             queue_batch_id=queue_item.batch_id,
             queue_item_id=queue_item.item_id,
             queue_id=queue_item.queue_id,
@@ -150,13 +150,13 @@ class DefaultSessionRunner(SessionRunnerBase):
         stacktrace = get_stacktrace(exc_type, exc_value, exc_traceback)
 
         queue_item.session.set_node_error(invocation.id, stacktrace)
-        self.services.logger.error(
+        self._services.logger.error(
             f"Error while invoking session {queue_item.session_id}, invocation {invocation.id} ({invocation.get_type()}):\n{exc_type}"
         )
-        self.services.logger.error(stacktrace)
+        self._services.logger.error(stacktrace)
 
         # Send error event
-        self.services.events.emit_invocation_error(
+        self._services.events.emit_invocation_error(
             queue_batch_id=queue_item.session_id,
             queue_item_id=queue_item.item_id,
             queue_id=queue_item.queue_id,
@@ -176,7 +176,7 @@ class DefaultSessionRunner(SessionRunnerBase):
         """Run a single node in the graph"""
         try:
             # Any unhandled exception is an invocation error & will fail the graph
-            with self.services.performance_statistics.collect_stats(invocation, queue_item.session_id):
+            with self._services.performance_statistics.collect_stats(invocation, queue_item.session_id):
                 self._on_before_run_node(invocation, queue_item)
 
                 data = InvocationContextData(
@@ -186,12 +186,12 @@ class DefaultSessionRunner(SessionRunnerBase):
                 )
                 context = build_invocation_context(
                     data=data,
-                    services=self.services,
-                    cancel_event=self.cancel_event,
+                    services=self._services,
+                    cancel_event=self._cancel_event,
                 )
 
                 # Invoke the node
-                outputs = invocation.invoke_internal(context=context, services=self.services)
+                outputs = invocation.invoke_internal(context=context, services=self._services)
                 # Save outputs and history
                 queue_item.session.complete(invocation.id, outputs)