sure B<cpufreqd> (L<http://cpufreqd.sourceforge.net/>) or a similar tool is
installed and an "cpu governor" (that's a kernel module) is loaded.
+If the system has the I<cpufreq-stats> kernel module loaded, this plugin reports
+the rate of p-state (cpu frequency) transitions and the percentage of time spent
+in each p-state.
+
=head2 Plugin C<cpusleep>
This plugin doesn't have any options. It reads CLOCK_BOOTTIME and
=back
-=head2 Plugin C<gpu_nvml>
+=head2 Plugin C<gpu_nvidia>
-Collects various statistics from the system's NVIDIA GPUs using the NVML
-library. Currently collected are fan speed, core temperature, percent load, and
-percent memory used.
+Efficiently collects various statistics from the system's NVIDIA GPUs using the
+NVML library. Currently collected are fan speed, core temperature, percent
+load, percent memory used, compute and memory frequencies, and power
+consumption.
=over 4
if there is only one package and C<pkgE<lt>nE<gt>-coreE<lt>mE<gt>> if there is
more than one, where I<n> is the n-th core of package I<m>.
+=item B<RestoreAffinityPolicy> I<AllCPUs>|I<Restore>
+
+Reading data from CPU has side-effect: collectd process's CPU affinity mask
+changes. After reading data is completed, affinity mask needs to be restored.
+This option allows to set restore policy.
+
+B<AllCPUs> (the default): Restore the affinity by setting affinity to any/all
+CPUs.
+
+B<Restore>: Save affinity using sched_getaffinity() before reading data and
+restore it after.
+
+On some systems, sched_getaffinity() will fail due to inconsistency of the CPU
+set size between userspace and kernel. In these cases plugin will detect the
+unsuccessful call and fail with an error, preventing data collection.
+Most of configurations does not need to save affinity as Collectd process is
+allowed to run on any/all available CPUs.
+
+If you need to save and restore affinity and get errors like 'Unable to save
+the CPU affinity', setting 'possible_cpus' kernel boot option may also help.
+
+See following links for details:
+
+L<https://github.com/collectd/collectd/issues/1593>
+L<https://sourceware.org/bugzilla/show_bug.cgi?id=15630>
+L<https://bugzilla.kernel.org/show_bug.cgi?id=151821>
+
=back
=head2 Plugin C<unixsock>
Only I<Connection> is required.
+Consider the following example config:
+
+ <Plugin "virt">
+ Connection "qemu:///system"
+ HostnameFormat "hostname"
+ InterfaceFormat "address"
+ PluginInstanceFormat "name"
+ </Plugin>
+
+It will generate the following values:
+
+ node42.example.com/virt-instance-0006f26c/disk_octets-vda
+ node42.example.com/virt-instance-0006f26c/disk_ops-vda
+ node42.example.com/virt-instance-0006f26c/if_dropped-ca:fe:ca:fe:ca:fe
+ node42.example.com/virt-instance-0006f26c/if_errors-ca:fe:ca:fe:ca:fe
+ node42.example.com/virt-instance-0006f26c/if_octets-ca:fe:ca:fe:ca:fe
+ node42.example.com/virt-instance-0006f26c/if_packets-ca:fe:ca:fe:ca:fe
+ node42.example.com/virt-instance-0006f26c/memory-actual_balloon
+ node42.example.com/virt-instance-0006f26c/memory-available
+ node42.example.com/virt-instance-0006f26c/memory-last_update
+ node42.example.com/virt-instance-0006f26c/memory-major_fault
+ node42.example.com/virt-instance-0006f26c/memory-minor_fault
+ node42.example.com/virt-instance-0006f26c/memory-rss
+ node42.example.com/virt-instance-0006f26c/memory-swap_in
+ node42.example.com/virt-instance-0006f26c/memory-swap_out
+ node42.example.com/virt-instance-0006f26c/memory-total
+ node42.example.com/virt-instance-0006f26c/memory-unused
+ node42.example.com/virt-instance-0006f26c/memory-usable
+ node42.example.com/virt-instance-0006f26c/virt_cpu_total
+ node42.example.com/virt-instance-0006f26c/virt_vcpu-0
+
+You can get information on the metric's units from the online libvirt documentation.
+For instance, I<virt_cpu_total> is in nanoseconds.
+
=over 4
=item B<Connection> I<uri>
Setting C<BlockDeviceFormatBasename true> will cause the I<type instance> to be
set to C<image1.qcow2>.
-=item B<HostnameFormat> B<name|uuid|hostname|...>
+=item B<HostnameFormat> B<name|uuid|hostname|metadata...>
When the virt plugin logs data, it sets the hostname of the collected data
according to this setting. The default is to use the guest name as provided by
same guest across migrations.
B<hostname> means to use the global B<Hostname> setting, which is probably not
-useful on its own because all guests will appear to have the same name.
+useful on its own because all guests will appear to have the same name. This is
+useful in conjunction with B<PluginInstanceFormat> though.
+
+B<metadata> means use information from guest's metadata. Use
+B<HostnameMetadataNS> and B<HostnameMetadataXPath> to localize this information.
You can also specify combinations of these fields. For example B<name uuid>
means to concatenate the guest name and UUID (with a literal colon character
B<address> means use the interface's mac address. This is useful since the
interface path might change between reboots of a guest or across migrations.
-=item B<PluginInstanceFormat> B<name|uuid|none>
+=item B<PluginInstanceFormat> B<name|uuid|metadata|none>
When the virt plugin logs data, it sets the plugin_instance of the collected
data according to this setting. The default is to not set the plugin_instance.
B<name> means use the guest's name as provided by the hypervisor.
B<uuid> means use the guest's UUID.
+B<metadata> means use information from guest's metadata.
You can also specify combinations of the B<name> and B<uuid> fields.
For example B<name uuid> means to concatenate the guest name and UUID
(with a literal colon character between, thus I<"foo:1234-1234-1234-1234">).
+=item B<HostnameMetadataNS> B<string>
+
+When B<metadata> is used in B<HostnameFormat> or B<PluginInstanceFormat>, this
+selects in which metadata namespace we will pick the hostname. The default is
+I<http://openstack.org/xmlns/libvirt/nova/1.0>.
+
+=item B<HostnameMetadataXPath> B<string>
+
+When B<metadata> is used in B<HostnameFormat> or B<PluginInstanceFormat>, this
+describes where the hostname is located in the libvirt metadata. The default is
+I</instance/name/text()>.
+
=item B<Instances> B<integer>
How many read instances you want to use for this plugin. The default is one,
=back
=item B<PersistentNotification> B<true>|B<false>
+
Override default configuration to only send notifications when there is a change
in the lifecycle state of a domain. When set to true notifications will be sent
for every read cycle. Default is false. Does not affect the stats being
dispatched.
+=item B<Instances> B<integer>
+
+How many read instances you want to use for this plugin. The default is one,
+and the sensible setting is a multiple of the B<ReadThreads> value.
+
+This option is only useful then domains are specially tagged.
+If you are not sure, just use the default setting.
+
+The reader instance will only query the domains with attached a matching tag.
+Tags should have the form of 'virt-X' where X is reader instance number,
+starting from 0.
+
+The special-purpose reader instance #0, guaranteed to be always present,
+will query all the domains with missing or unrecognized tag, so no domain will
+ever left out.
+
+Domain tagging is done with custom attribute in the libvirt domain metadata
+section. Value is taken by XPath I</domain/metadata/ovirtmap/tag/text()>
+expression in I<http://ovirt.org/ovirtmap/tag/1.0> namespace.
+(XPath and namespace values are not configurable yet).
+
+Tagging could be used by management application to evenly spread the
+load among the reader threads, or to pin on the same threads all
+the libvirt domains which use the same shared storage, to minimize
+the disruption in presence of storage outages.
+
=back
=head2 Plugin C<vmem>
=over 4
+=item B<Host> I<Host>
+
+Bind to the hostname / address I<Host>. By default, the plugin will bind to the
+"any" address, i.e. accept packets sent to any of the hosts addresses.
+
+This option is supported only for libmicrohttpd newer than 0.9.0.
+
=item B<Port> I<Port>
Port the embedded webserver should listen on. Defaults to B<9103>.
=back
+=head2 Plugin C<write_stackdriver>
+
+The C<write_stackdriver> plugin writes metrics to the
+I<Google Stackdriver Monitoring> service.
+
+This plugin supports two authentication methods: When configured, credentials
+are read from the JSON credentials file specified with B<CredentialFile>.
+Alternatively, when running on
+I<Google Compute Engine> (GCE), an I<OAuth> token is retrieved from the
+I<metadata server> and used to authenticate to GCM.
+
+B<Synopsis:>
+
+ <Plugin write_stackdriver>
+ CredentialFile "/path/to/service_account.json"
+ <Resource "global">
+ Label "project_id" "monitored_project"
+ </Resource>
+ </Plugin>
+
+=over 4
+
+=item B<CredentialFile> I<file>
+
+Path to a JSON credentials file holding the credentials for a GCP service
+account.
+
+If B<CredentialFile> is not specified, the plugin uses I<Application Default
+Credentials>. That means which credentials are used depends on the environment:
+
+=over 4
+
+=item
+
+The environment variable C<GOOGLE_APPLICATION_CREDENTIALS> is checked. If this
+variable is specified it should point to a JSON file that defines the
+credentials.
+
+=item
+
+The path C<${HOME}/.config/gcloud/application_default_credentials.json> is
+checked. This where credentials used by the I<gcloud> command line utility are
+stored. You can use C<gcloud auth application-default login> to create these
+credentials.
+
+Please note that these credentials are often of your personal account, not a
+service account, and are therefore unfit to be used in a production
+environment.
+
+=item
+
+When running on GCE, the built-in service account associated with the virtual
+machine instance is used.
+See also the B<Email> option below.
+
+=back
+
+=item B<Project> I<Project>
+
+The I<Project ID> or the I<Project Number> of the I<Stackdriver Account>. The
+I<Project ID> is a string identifying the GCP project, which you can chose
+freely when creating a new project. The I<Project Number> is a 12-digit decimal
+number. You can look up both on the I<Developer Console>.
+
+This setting is optional. If not set, the project ID is read from the
+credentials file or determined from the GCE's metadata service.
+
+=item B<Email> I<Email> (GCE only)
+
+Choses the GCE I<Service Account> used for authentication.
+
+Each GCE instance has a C<default> I<Service Account> but may also be
+associated with additional I<Service Accounts>. This is often used to restrict
+the permissions of services running on the GCE instance to the required
+minimum. The I<write_stackdriver plugin> requires the
+C<https://www.googleapis.com/auth/monitoring> scope. When multiple I<Service
+Accounts> are available, this option selects which one is used by
+I<write_stackdriver plugin>.
+
+=item B<Resource> I<ResourceType>
+
+Configures the I<Monitored Resource> to use when storing metrics.
+More information on I<Monitored Resources> and I<Monitored Resource Types> are
+available at L<https://cloud.google.com/monitoring/api/resources>.
+
+This block takes one string argument, the I<ResourceType>. Inside the block are
+one or more B<Label> options which configure the resource labels.
+
+This block is optional. The default value depends on the runtime environment:
+on GCE, the C<gce_instance> resource type is used, otherwise the C<global>
+resource type ist used:
+
+=over 4
+
+=item
+
+B<On GCE>, defaults to the equivalent of this config:
+
+ <Resource "gce_instance">
+ Label "project_id" "<project_id>"
+ Label "instance_id" "<instance_id>"
+ Label "zone" "<zone>"
+ </Resource>
+
+The values for I<project_id>, I<instance_id> and I<zone> are read from the GCE
+metadata service.
+
+=item
+
+B<Elsewhere>, i.e. not on GCE, defaults to the equivalent of this config:
+
+ <Resource "global">
+ Label "project_id" "<Project>"
+ </Resource>
+
+Where I<Project> refers to the value of the B<Project> option or the project ID
+inferred from the B<CredentialFile>.
+
+=back
+
+=item B<Url> I<Url>
+
+URL of the I<Stackdriver Monitoring> API. Defaults to
+C<https://monitoring.googleapis.com/v3>.
+
+=back
+
=head2 Plugin C<xencpu>
This plugin collects metrics of hardware CPU load for machine running Xen