Correct osutil and add tests for threshold

azurelinuxagent/common/cgroups.py

@@ -186,8 +186,6 @@ class CGroupsTelemetry(object):
 
     tracked_names = set()
 
-    _osutil = get_osutil()
-
     @staticmethod
     def metrics_hierarchies():
         return CGroupsTelemetry._hierarchies
@@ -269,24 +267,6 @@ def stop_tracking(name):
         if CGroupsTelemetry.is_tracked(name):
             del (CGroupsTelemetry._tracked[name])
 
-    @staticmethod
-    def get_cpu_limits(name):
-        # default values
-        cpu_limit = DEFAULT_CPU_LIMIT_AGENT if AGENT_NAME.lower() in name.lower() else DEFAULT_CPU_LIMIT_EXT
-
-        return cpu_limit
-
-    @staticmethod
-    def get_memory_limits(name):
-        # default values
-        mem_limit = max(DEFAULT_MEM_LIMIT_MIN_MB, round(_osutil.get_total_mem() * DEFAULT_MEM_LIMIT_PCT / 100, 0))
-
-        # agent values
-        if AGENT_NAME.lower() in name.lower():
-            mem_limit = min(DEFAULT_MEM_LIMIT_MAX_MB, mem_limit)
-
-        return mem_limit
-
     @staticmethod
     def collect_all_tracked():
         """
@@ -304,8 +284,7 @@ def collect_all_tracked():
         for cgroup_name, collector in CGroupsTelemetry._tracked.copy().items():
             cgroup_name = cgroup_name if cgroup_name else WRAPPER_CGROUP_NAME
             results[cgroup_name] = collector.collect()
-            limits[cgroup_name] = {"cpu": CGroupsTelemetry.get_cpu_limits(cgroup_name),
-                                   "memory": CGroupsTelemetry.get_memory_limits(cgroup_name)}
+            limits[cgroup_name] = collector.cgroup.threshold
 
         return results, limits
 
@@ -392,12 +371,12 @@ def _construct_systemd_path_for_hierarchy(hierarchy, cgroup_name):
         return os.path.join(BASE_CGROUPS, hierarchy, 'system.slice', cgroup_name).rstrip(os.path.sep)
 
     @staticmethod
-    def for_extension(name):
-        return CGroups(name, CGroups._construct_custom_path_for_hierarchy)
+    def for_extension(name, limits=None):
+        return CGroups(name, CGroups._construct_custom_path_for_hierarchy, limits)
 
     @staticmethod
-    def for_systemd_service(name):
-        return CGroups(name.lower(), CGroups._construct_systemd_path_for_hierarchy)
+    def for_systemd_service(name, limits=None):
+        return CGroups(name.lower(), CGroups._construct_systemd_path_for_hierarchy, limits)
 
     @staticmethod
     def enabled():
@@ -411,7 +390,7 @@ def disable():
     def enable():
         CGroups._enabled = True
 
-    def __init__(self, name, path_maker):
+    def __init__(self, name, path_maker, limits=None):
         """
         Construct CGroups object. Create appropriately-named directory for each hierarchy of interest.
 
@@ -426,7 +405,9 @@ def __init__(self, name, path_maker):
             self.is_wrapper_cgroup = False
 
         self.cgroups = {}
-        self.threshold = None
+
+        self.threshold = CGroupsLimits(self.name, cpu_threshold=limits["cpu"],
+                                       memory_threshold=limits["memory"]) if limits else CGroupsLimits(self.name)
 
         if not self.enabled():
             return
@@ -503,22 +484,6 @@ def add(self, pid):
             tasks_file = self._get_cgroup_file(hierarchy, 'cgroup.procs')
             fileutil.append_file(tasks_file, "{0}\n".format(pid))
 
-    def get_cpu_limits(self):
-        # default values
-        cpu_limit = DEFAULT_CPU_LIMIT_AGENT if AGENT_NAME.lower() in self.name.lower() else DEFAULT_CPU_LIMIT_EXT
-
-        return cpu_limit
-
-    def get_memory_limits(self):
-        # default values
-        mem_limit = max(DEFAULT_MEM_LIMIT_MIN_MB, round(self._osutil.get_total_mem() * DEFAULT_MEM_LIMIT_PCT / 100, 0))
-
-        # agent values
-        if AGENT_NAME.lower() in self.name.lower():
-            mem_limit = min(DEFAULT_MEM_LIMIT_MAX_MB, mem_limit)
-
-        return mem_limit
-
     def set_limits(self):
         """
         Set per-hierarchy limits based on the cgroup name (agent or particular extension)
@@ -535,9 +500,8 @@ def set_limits(self):
                 logger.info('No cgroups limits for {0}'.format(self.name))
                 return
 
-        # default values
-        cpu_limit = self.get_cpu_limits()
-        mem_limit = self.get_memory_limits()
+        cpu_limit = self.threshold.cpu_limit
+        mem_limit = self.threshold.memory_limit
 
         msg = '{0}: {1}% {2}mb'.format(self.name, cpu_limit, mem_limit)
         logger.info("Setting cgroups limits for {0}".format(msg))
@@ -815,3 +779,27 @@ def set_memory_limit(self, limit=None, unit='megabytes'):
             fileutil.write_file(memory_limit_file, '{0}\n'.format(value))
         else:
             raise CGroupsException("Memory hierarchy not available in this cgroup")
+
+
+class CGroupsLimits(object):
+    def __init__(self, cgroup_name, cpu_threshold=None, memory_threshold=None):
+        self.cpu_limit = cpu_threshold if cpu_threshold else self.get_default_cpu_limits(cgroup_name)
+        self.memory_limit = memory_threshold if memory_threshold else self.get_default_cpu_limits(cgroup_name)
+
+    @staticmethod
+    def get_default_cpu_limits(cgroup_name):
+        # default values
+        cpu_limit = DEFAULT_CPU_LIMIT_AGENT if AGENT_NAME.lower() in cgroup_name.lower() else DEFAULT_CPU_LIMIT_EXT
+        return cpu_limit
+
+    @staticmethod
+    def get_default_memory_limits(cgroup_name):
+        os_util = get_osutil()
+
+        # default values
+        mem_limit = max(DEFAULT_MEM_LIMIT_MIN_MB, round(os_util.get_total_mem() * DEFAULT_MEM_LIMIT_PCT / 100, 0))
+
+        # agent values
+        if AGENT_NAME.lower() in cgroup_name.lower():
+            mem_limit = min(DEFAULT_MEM_LIMIT_MAX_MB, mem_limit)
+        return mem_limit

azurelinuxagent/ga/monitor.py

@@ -427,7 +427,7 @@ def send_cgroup_telemetry(self):
                             report_metric(metric_group, metric_name, cgroup_name, value)
 
                         if metric_group == "Memory":
-                            if value >= thresholds["memory"]:
+                            if value >= thresholds.memory_limit:
                                 msg = "CGroup {0}: Crossed the Memory Threshold. Current Value:{1}, Threshold:{2}.".format(
                                     cgroup_name, value, thresholds["memory"])
                                 add_event(name=AGENT_NAME,
@@ -438,7 +438,7 @@ def send_cgroup_telemetry(self):
                                           log_event=True)
 
                         if metric_group == "Process":
-                            if value >= thresholds["cpu"]:
+                            if value >= thresholds.cpu_limit:
                                 msg = "CGroup {0}: Crossed the Processor Threshold. Current Value:{1}, Threshold:{2}.".format(
                                     cgroup_name, value, thresholds["cpu"])
                                 add_event(name=AGENT_NAME,

tests/common/test_cgroups.py

@@ -17,8 +17,8 @@
 
 from __future__ import print_function
 
-from azurelinuxagent.common.cgroups import CGroupsTelemetry, CGroups, CGroupsException, BASE_CGROUPS, Cpu, Memory, \
-    DEFAULT_MEM_LIMIT_MIN_MB
+from azurelinuxagent.common.cgroups import CGroupsTelemetry, CGroups, CGroupsException, CGroupsLimits, BASE_CGROUPS, \
+    Cpu, Memory, DEFAULT_MEM_LIMIT_MIN_MB
 from azurelinuxagent.common.version import AGENT_NAME
 from tests.tools import *
 
@@ -144,6 +144,11 @@ def exercise_telemetry_instantiation(self, test_cgroup):
             else:
                 self.fail("Unknown metric {0}/{1} value {2}".format(metric_family, metric_name, metric_value))
 
+        my_limits = limits[test_extension_name]
+        self.assertIsInstance(my_limits, CGroupsLimits, msg="is not the correct instance")
+        self.assertGreater(my_limits.cpu_limit, 0.0)
+        self.assertGreater(my_limits.memory_limit, 0.0)
+
     @skip_if_predicate_false(i_am_root, "Test does not run when non-root")
     def test_telemetry_instantiation_as_superuser(self):
         """