Merge pull request #33 from sergey-dryabzhinsky/container-cpu-usage-b…

…y-cgroup-cpuacct

Container cpu usage by cgroup cpuacct

lwp.py

@@ -767,13 +767,13 @@ def refresh_cpu_containers(name=None):
                 container = container.replace(' (auto)', '')
                 containers.append({
                     'name': container,
-                    'cpu': lwp.container_cpu_percent(container),
+                    'cpu': lwp.container_cpu_percent_cgroup(container),
                 })
             return jsonify(data=containers)
         elif name == 'host':
             return lwp.host_cpu_percent()
         return jsonify({
-            'cpu': lwp.container_cpu_percent(name),
+            'cpu': lwp.container_cpu_percent_cgroup(name),
         })
 
 

lwp/__init__.py

@@ -151,6 +151,32 @@ def container_cpu_percent(name):
         return '0'
     return out
 
+def container_cpu_percent_cgroup(name):
+    '''
+    returns CPU usage in percent
+    '''
+    if name in stopped():
+        return '0'
+
+    cont_usage_file = "/sys/fs/cgroup/cpuacct/lxc/%s/cpuacct.usage" % name
+    if not os.path.isfile(cont_usage_file):
+        return '-1'
+
+    f = open(cont_usage_file, 'r')
+    line = f.readline().strip()
+    prev_cont_usage_ns = float(line) * 10**-9
+    f.close()
+
+    time.sleep(0.1)
+
+    f = open(cont_usage_file, 'r')
+    line = f.readline().strip()
+    current_cont_usage_ns = float(line) * 10**-9
+    f.close()
+
+    percent = 100 * (current_cont_usage_ns - prev_cont_usage_ns) / 0.1
+    return str('%.1f' % percent)
+
 
 def get_template_help(name):
     cmd = ["lxc-create -t %s -h" % name]