limit what data is collected via the config

README.md

@@ -16,6 +16,20 @@ Get VMWare VCenter information:
 
 Alternatively, if you don't wish to install the package, run using `$ vmware_exporter/vmware_exporter.py`
 
+### Limiting data collection
+
+Large installations may have trouble collecting all of the data in a timely fashion,
+so you can limit which subsystems are collected by adding a
+`collect_only` argument the config section, e.g. under `default`:
+
+    collect_only:
+    #   - vms
+      - datastores
+      - hosts
+
+would skip collecting information on the VMs. If there is no `collect_only`
+argument, everything will be collected as normal.
+
 ### Prometheus configuration
 
 You can use the following parameters in prometheus configuration file. The `params` section is used to manage multiple login/passwords.

config.yml.sample

@@ -7,3 +7,12 @@ esx:
     vmware_user: 'root'
     vmware_password: 'password'
     ignore_ssl: True
+
+limited:
+    vmware_user: '[email protected]'
+    vmware_password: 'password'
+    ignore_ssl: True
+    collect_only:
+    #   - vms
+      - datastores
+      - hosts

vmware_exporter/vmware_exporter.py

@@ -97,7 +97,8 @@ def collect(self, target=None, section='default'):
         if section not in self.config.keys():
             print("{} is not a valid section, using default".format(section))
             section='default'
-        metrics = {
+        metric_list ={}
+        metric_list['vms'] = {
                     'vmware_vm_power_state': GaugeMetricFamily(
                         'vmware_vm_power_state',
                         'VMWare VM Power state (On / Off)',
@@ -117,7 +118,9 @@ def collect(self, target=None, section='default'):
                     'vmware_vm_num_cpu': GaugeMetricFamily(
                         'vmware_vm_num_cpu',
                         'VMWare Number of processors in the virtual machine',
-                        labels=['vm_name', 'host_name']),
+                        labels=['vm_name', 'host_name'])
+                    }
+        metric_list['datastores'] = {
                     'vmware_datastore_capacity_size': GaugeMetricFamily(
                         'vmware_datastore_capacity_size',
                         'VMWare Datasore capacity in bytes',
@@ -141,7 +144,9 @@ def collect(self, target=None, section='default'):
                     'vmware_datastore_vms': GaugeMetricFamily(
                         'vmware_datastore_vms',
                         'VMWare Virtual Machines number using this datastore',
-                        labels=['ds_name']),
+                        labels=['ds_name'])
+                        }
+        metric_list['hosts'] = {
                     'vmware_host_power_state': GaugeMetricFamily(
                         'vmware_host_power_state',
                         'VMWare Host Power state (On / Off)',
@@ -167,6 +172,19 @@ def collect(self, target=None, section='default'):
                         'VMWare Host Memory Max availability in Mbytes',
                         labels=['host_name']),
                 }
+        collect_subsystems = self._collect_subsystems(section, metric_list.keys())
+
+
+        metrics = {}
+        for s in collect_subsystems:
+            metrics.update(metric_list[s])
+
+
+        collect_subsystems = self._collect_subsystems(section, metric_list.keys())
+
+        metrics = {}
+        for s in collect_subsystems:
+            metrics.update(metric_list[s])
 
         print("[{0}] Start collecting vcenter metrics for {1}".format(datetime.utcnow().replace(tzinfo=pytz.utc), target))
 
@@ -177,28 +195,34 @@ def collect(self, target=None, section='default'):
 
         content = self.si.RetrieveContent()
 
-        # Get performance metrics counter information
-        counter_info = self._vmware_perf_metrics(content)
+        if 'vms' in collect_subsystems:
+            # Get performance metrics counter information
+            counter_info = self._vmware_perf_metrics(content)
 
-        # Fill Snapshots (count and age)
-        vm_counts, vm_ages = self._vmware_get_snapshots(content)
-        for v in vm_counts:
-            metrics['vmware_vm_snapshots'].add_metric([v['vm_name']],
-                                                            v['snapshot_count'])
-        for vm_age in vm_ages:
-            for v in vm_age:
-                metrics['vmware_vm_snapshot_timestamp_seconds'].add_metric([v['vm_name'],
-                                        v['vm_snapshot_name']],
-                                        v['vm_snapshot_timestamp_seconds'])
 
-        # Fill Datastore
-        self._vmware_get_datastores(content, metrics)
+            # Fill VM Informations
+            self._vmware_get_vms(content, metrics, counter_info)
 
-        # Fill VM Informations
-        self._vmware_get_vms(content, metrics, counter_info)
+            # Fill Snapshots (count and age)
+            vm_counts, vm_ages = self._vmware_get_snapshots(content)
+            for v in vm_counts:
+                metrics['vmware_vm_snapshots'].add_metric([v['vm_name']],
+                                                                v['snapshot_count'])
+            for vm_age in vm_ages:
+                for v in vm_age:
+                    metrics['vmware_vm_snapshot_timestamp_seconds'].add_metric([v['vm_name'],
+                                            v['vm_snapshot_name']],
+                                            v['vm_snapshot_timestamp_seconds'])
+
+
+        # Fill Datastore
+        if 'datastores' in collect_subsystems:
+            self._vmware_get_datastores(content, metrics)
 
         # Fill Hosts Informations
-        self._vmware_get_hosts(content, metrics)
+        if 'hosts' in collect_subsystems:
+            self._vmware_get_hosts(content, metrics)
+
 
         print("[{0}] Stop collecting vcenter metrics for {1}".format(datetime.utcnow().replace(tzinfo=pytz.utc), target))
 
@@ -207,8 +231,50 @@ def collect(self, target=None, section='default'):
         for metricname, metric in metrics.items():
             yield metric
 
+    def _collect_subsystems(self, section, valid_subsystems):
+        """
+          Return the list of subsystems to collect - everything by default, a
+          subset if the config section has collect_only specified
+        """
+        collect_subsystems = []
+
+        if not self.config[section].get('collect_only'):
+            collect_subsystems = valid_subsystems
+        else:
+            for subsystem in self.config[section].get('collect_only'):
+                if subsystem in valid_subsystems:
+                    collect_subsystems.append(subsystem)
+                else:
+                    print("invalid subsystem specified in collect_only: " + str(subsystem))
+
+            if not collect_subsystems:
+                print("no valid subystems specified in collect_only, collecting everything")
+                collect_subsystems = valid_subsystems
+
+        return collect_subsystems
+
+
+    def _collect_subsystems(self, section, valid_subsystems):
+        """
+          Return the list of subsystems to collect - everything by default, a
+          subset if the config section has collect_only specified
+        """
+        collect_subsystems = []
+
+        if not self.config[section].get('collect_only'):
+            collect_subsystems = valid_subsystems
+        else:
+            for subsystem in self.config[section].get('collect_only'):
+                if subsystem in valid_subsystems:
+                    collect_subsystems.append(subsystem)
+                else:
+                    print("invalid subsystem specified in collect_only: " + str(subsystem))
 
+            if not collect_subsystems:
+                print("no valid subystems specified in collect_only, collecting everything")
+                collect_subsystems = valid_subsystems
 
+        return collect_subsystems
 
     def _to_unix_timestamp(self, my_date):
         return ((my_date - datetime(1970,1,1,tzinfo=pytz.utc)).total_seconds())