invoke C fun + write test for percent usagewin-swap-usage-via-pagefiles

4 files changed, 14 insertions, 12 deletions

diff --git a/psutil/_psutil_windows.c b/psutil/_psutil_windows.c
index 6e51c449..6b6d3103 100644
--- a/psutil/_psutil_windows.c
+++ b/psutil/_psutil_windows.c
@@ -1596,6 +1596,7 @@ PsutilMethods[] = {
     {"cpu_times", psutil_cpu_times, METH_VARARGS},
     {"disk_io_counters", psutil_disk_io_counters, METH_VARARGS},
     {"disk_partitions", psutil_disk_partitions, METH_VARARGS},
+    {"disk_swaps", psutil_disk_swaps, METH_VARARGS},
     {"disk_usage", psutil_disk_usage, METH_VARARGS},
     {"getloadavg", (PyCFunction)psutil_get_loadavg, METH_VARARGS},
     {"getpagesize", psutil_getpagesize, METH_VARARGS},
diff --git a/psutil/_pswindows.py b/psutil/_pswindows.py
index b546f15d..80cd3211 100644
--- a/psutil/_pswindows.py
+++ b/psutil/_pswindows.py
@@ -241,18 +241,13 @@ def virtual_memory():
 
 def swap_memory():
     """Swap system memory as a (total, used, free, sin, sout) tuple."""
-    mem = cext.virtual_mem()
-
-    total_phys = mem[0]
-    free_phys = mem[1]
-    total_system = mem[2]
-    free_system = mem[3]
-
-    # system memory (commit total/limit) is the sum of physical and swap
-    # thus physical memory values need to be substracted to get swap values
-    total = total_system - total_phys
-    free = min(total, free_system - free_phys)
-    used = total - free
+    total = used = 0
+    pagefiles = cext.disk_swaps()
+    for pf in pagefiles:
+        path, total_size, total_in_use, peak_usage = pf
+        total += total_size
+        used += total_in_use
+    free = total - used
     percent = usage_percent(used, total, round_=1)
     return _common.sswap(total, used, free, percent, 0, 0)
 
diff --git a/psutil/arch/windows/disk.h b/psutil/arch/windows/disk.h
index 28bed22b..e0a7f895 100644
--- a/psutil/arch/windows/disk.h
+++ b/psutil/arch/windows/disk.h
@@ -8,5 +8,6 @@
 
 PyObject *psutil_disk_io_counters(PyObject *self, PyObject *args);
 PyObject *psutil_disk_partitions(PyObject *self, PyObject *args);
+PyObject *psutil_disk_swaps(PyObject *self, PyObject *args);
 PyObject *psutil_disk_usage(PyObject *self, PyObject *args);
 PyObject *psutil_QueryDosDevice(PyObject *self, PyObject *args);
diff --git a/psutil/tests/test_windows.py b/psutil/tests/test_windows.py
index cb2642d1..478e9010 100755
--- a/psutil/tests/test_windows.py
+++ b/psutil/tests/test_windows.py
@@ -162,6 +162,11 @@ class TestSystemAPIs(WindowsTestCase):
             int(w.AvailableBytes), psutil.virtual_memory().free,
             delta=TOLERANCE_SYS_MEM)
 
+    def test_percent_swapmem(self):
+        w = wmi.WMI().Win32_PerfRawData_PerfOS_PagingFile()[0]
+        percent = int(w.PercentUsage) * 100 / int(w.PercentUsage_Base)
+        self.assertEqual(int(percent), int(psutil.swap_memory().percent))
+
     # @unittest.skipIf(wmi is None, "wmi module is not installed")
     # def test__UPTIME(self):
     #     # _UPTIME constant is not public but it is used internally