Address Victor's comments.

pyperf/_manager.py

@@ -7,6 +7,8 @@
 from pyperf._utils import MS_WINDOWS, create_environ, create_pipe, popen_killer
 
 
+EXIT_TIMEOUT = 60
+
 # Limit to 5 calibration processes
 # (10 if calibration is needed for loops and warmups)
 MAX_CALIBRATION = 5
@@ -107,7 +109,7 @@ def spawn_worker(self, calibrate_loops, calibrate_warmups):
             with popen_killer(proc):
                 try:
                     bench_json = rpipe.read_text()
-                    exitcode = proc.wait()
+                    exitcode = proc.wait(timeout=EXIT_TIMEOUT)
                 except TimeoutError as exc:
                     print(exc)
                     sys.exit(124)

pyperf/_utils.py

@@ -327,26 +327,25 @@ def open_text(self):
 
     def read_text(self):
         with self.open_text() as rfile:
-            if self._timeout:
-              return self._read_text_timeout(rfile, self._timeout)
+            if self._timeout is not None:
+                return self._read_text_timeout(rfile, self._timeout)
             else:
                 return rfile.read()
 
     def _read_text_timeout(self, rfile, timeout):
-        start_time = time.time()
+        start_time = time.monotonic()
+        output = []
         while True:
-            if time.time() - start_time > timeout:
+            if time.monotonic() - start_time > timeout:
                 raise TimeoutError(f"Timed out after {timeout} seconds")
             ready, _, _ = select.select([rfile], [], [], timeout)
-            if ready:
-                data = rfile.read()
-                if data:
-                    return data
-                else:
-                    break
-            else:
-                pass
-
+            if not ready:
+                continue
+            data = rfile.read(1024)
+            if not data:
+                break
+            output.append(data)
+        return "".join(output)
 
 
 class WritePipe(_Pipe):

pyperf/tests/test_runner.py

@@ -150,7 +150,7 @@ def test_pipe(self):
                          tests.benchmark_as_json(result.bench))
 
     def test_pipe_with_timeout(self):
-        rpipe, wpipe = create_pipe(timeout=1)
+        rpipe, wpipe = create_pipe(timeout=0.1)
         with rpipe:
             with wpipe:
                 arg = wpipe.to_subprocess()
@@ -165,7 +165,7 @@ def test_pipe_with_timeout(self):
                 with self.assertRaises(TimeoutError) as cm:
                     rpipe.read_text()
                 self.assertEqual(str(cm.exception),
-                         'Timed out after 1 seconds')
+                         'Timed out after 0.1 seconds')
 
     def test_json_exists(self):
         with tempfile.NamedTemporaryFile('wb+') as tmp: