fix #614: [Linux] return the num of physical cores instead of physica…

…l CPUs

CREDITS

@@ -298,3 +298,8 @@ N: desbma
 W: https://github.com/desbma
 C: France
 I: 628
+
+N: John Burnett
+W: http://www.johnburnett.com/
+C: Irvine, CA, US
+I: 614

HISTORY.rst

@@ -37,6 +37,8 @@ Bug tracker at https://github.com/giampaolo/psutil/issues
 - #593: [FreeBSD] Process().memory_maps() segfaults.
 - #606: Process.parent() may swallow NoSuchProcess exceptions.
 - #611: [SunOS] net_io_counters has send and received swapped
+- #614: [Linux]: cpu_count(logical=False) return the number of physical CPUs
+  instead of physical cores.
 - #618: [SunOS] swap tests fail on Solaris when run as normal user
 - #628: [Linux] Process.name() truncates process name in case it contains
   spaces or parentheses.

psutil/__init__.py

@@ -1342,7 +1342,7 @@ def cpu_count(logical=True):
     os.cpu_count() in Python 3.4).
 
     If logical is False return the number of physical cores only
-    (hyper thread CPUs are excluded).
+    (e.g. hyper thread CPUs are excluded).
 
     Return None if undetermined.
 

psutil/_pslinux.py

@@ -276,14 +276,28 @@ def cpu_count_logical():
 
 
 def cpu_count_physical():
-    """Return the number of physical CPUs in the system."""
+    """Return the number of physical cores in the system."""
+    mapping = {}
+    current_info = {}
     with open('/proc/cpuinfo', 'rb') as f:
-        found = set()
         for line in f:
-            if line.lower().startswith(b'physical id'):
-                found.add(line.strip())
+            line = line.strip().lower()
+            if not line:
+                # new section
+                if (b'physical id' in current_info and
+                        b'cpu cores' in current_info):
+                    mapping[current_info[b'physical id']] = \
+                        current_info[b'cpu cores']
+                current_info = {}
+            else:
+                # ongoing section
+                if (line.startswith(b'physical id') or
+                        line.startswith(b'cpu cores')):
+                    key, value = line.split(b'\t:', 1)
+                    current_info[key] = int(value)
+
     # mimic os.cpu_count()
-    return len(found) if found else None
+    return sum(mapping.values()) or None
 
 
 # --- other system functions

test/_linux.py

@@ -204,6 +204,17 @@ def test_net_if_names(self):
         self.assertEqual(len(nics), found, msg="%s\n---\n%s" % (
             pprint.pformat(nics), out))
 
+    @unittest.skipUnless(which("nproc"), "nproc utility not available")
+    def test_cpu_count_logical_w_nproc(self):
+        num = int(sh("nproc --all"))
+        self.assertEqual(psutil.cpu_count(logical=True), num)
+
+    @unittest.skipUnless(which("lscpu"), "lscpu utility not available")
+    def test_cpu_count_logical_w_lscpu(self):
+        out = sh("lscpu -p")
+        num = len([x for x in out.split('\n') if not x.startswith('#')])
+        self.assertEqual(psutil.cpu_count(logical=True), num)
+
     # --- tests for specific kernel versions
 
     @unittest.skipUnless(