Tighten comments

Author: tonghuaroot

Lib/profiling/sampling/stack_collector.py

@@ -67,8 +67,7 @@ def export(self, filename):
         return True
 
 
-# Extra recursion budget for the recursive flamegraph tree walk during export,
-# large enough to cover the unwinder's maximum captured stack depth.
+# Bounded by the unwinder's maximum captured stack depth (MAX_FRAMES).
 _FLAMEGRAPH_RECURSION_MARGIN = 2000
 
 
@@ -168,10 +167,7 @@ def set_replay_stats(self, info):
         )
 
     def export(self, filename):
-        # The flamegraph tree is as deep as the deepest sampled stack and is
-        # walked recursively here (and by json.dumps), so raise the recursion
-        # limit while exporting. The remote unwinder caps stack depth at
-        # MAX_FRAMES, so this margin is bounded.
+        # export() and json.dumps() recurse to the sampled stack depth.
         old_limit = sys.getrecursionlimit()
         sys.setrecursionlimit(old_limit + _FLAMEGRAPH_RECURSION_MARGIN)
         try:

Lib/test/test_profiling/test_sampling_profiler/test_collectors.py

@@ -596,8 +596,7 @@ def test_flamegraph_deep_stack_export(self):
         self.addCleanup(close_and_unlink, flamegraph_out)
 
         collector = FlamegraphCollector(1000)
-        # Deeper than the default recursion limit; the tree walk in export()
-        # used to blow up here.
+        # Deeper than the default recursion limit.
         frames = [MockFrameInfo("f.py", i + 1, f"f{i}") for i in range(1536)]
         collector.collect(
             [MockInterpreterInfo(0, [MockThreadInfo(1, frames)])])