profiler: flush after writing the profiler output

Otherwise, the profiler output might only partially appears until the next flush
of the buffer. Since profiling often happens for long operation, the next flush
can be a long time away.

mercurial/profiling.py

@@ -70,6 +70,7 b' def lsprofile(ui, fp):'
             stats = lsprof.Stats(p.getstats())
             stats.sort(pycompat.sysstr(field))
             stats.pprint(limit=limit, file=fp, climit=climit)
+        fp.flush()
 
 
 @contextlib.contextmanager
@@ -97,14 +98,15 b' def flameprofile(ui, fp):'
     finally:
         thread.stop()
         thread.join()
-        print(
-            b'Collected %d stack frames (%d unique) in %2.2f seconds.'
-            % (
+        m = b'Collected %d stack frames (%d unique) in %2.2f seconds.'
+        m %= (
+            (
                 util.timer() - start_time,
                 thread.num_frames(),
                 thread.num_frames(unique=True),
-            )
+            ),
         )
+        print(m, flush=True)
 
 
 @contextlib.contextmanager
@@ -170,6 +172,7 b' def statprofile(ui, fp):'
             kwargs['showtime'] = showtime
 
         statprof.display(fp, data=data, format=displayformat, **kwargs)
+        fp.flush()
 
 
 class profile: