Address comments

python/tests/test_provenance.py

@@ -32,7 +32,7 @@
 try:
     import resource
 except ImportError:
-    resource = None  # resource.getrusage absent on windows
+    resource = None  # resource absent on windows
 
 
 import msprime
@@ -221,28 +221,29 @@ def test_libraries(self):
 
 
 class TestGetResources:
-    def test_used_resources_keys(self):
-        resources = provenance.get_resources(_start_time)
+    def test_get_resources_keys(self):
+        resources = provenance.get_resources(0)
         assert "elapsed_time" in resources
         assert "user_time" in resources
         assert "sys_time" in resources
         if resource is not None:
             assert "max_memory" in resources
 
-    def test_used_resources_values(self):
-        resources = provenance.get_resources(_start_time)
+    def test_get_resources_values(self):
+        delta = 0.1
+        resources = provenance.get_resources(time.time() - delta)
         assert isinstance(resources["elapsed_time"], float)
         assert isinstance(resources["user_time"], float)
         assert isinstance(resources["sys_time"], float)
-        assert resources["elapsed_time"] > 0.0001
-        assert resources["user_time"] > 0.0001
-        assert resources["sys_time"] > 0.0001
+        assert resources["elapsed_time"] >= delta
+        assert resources["user_time"] > 0
+        assert resources["sys_time"] > 0
         if resource is not None:
             assert isinstance(resources["max_memory"], int)
             assert resources["max_memory"] > 1024
 
-    def test_used_resources_platform(self):
-        resources = provenance.get_resources(_start_time)
+    def test_get_resources_platform(self):
+        resources = provenance.get_resources(0)
         if sys.platform != "darwin" and resource is not None:
             assert resources["max_memory"] % 1024 == 0
 

python/tskit/provenance.py

@@ -88,11 +88,10 @@ def get_resources(start_time):
         "sys_time": times.system + times.children_system,
     }
     if resource is not None:
-        # Don't report max memory on Windows. We could do this using the psutil lib, via
-        # psutil.Process(os.getpid()).get_ext_memory_info().peak_wset if demand exists
+        # Don't report max memory on Windows, we would need an external dep like psutil
         ret["max_memory"] = resource.getrusage(resource.RUSAGE_SELF).ru_maxrss
         if sys.platform != "darwin":
-            ret["max_memory"] *= 1024  # Linux, freeBSD et al reports in KB, not bytes
+            ret["max_memory"] *= 1024  # Linux, freeBSD et al reports in KiB, not bytes
 
     return ret