=item B<GaugeAverage>
-Calculate the average.
+Calculate the average of all values matched during the interval.
=item B<GaugeMin>
-Use the smallest number only.
+Report the smallest value matched during the interval.
=item B<GaugeMax>
-Use the greatest number only.
+Report the greatest value matched during the interval.
=item B<GaugeLast>
-Use the last number found.
+Report the last value matched during the interval.
=item B<GaugePersist>
-Use the last number found. The number is not reset at the end of an interval.
-It is continously reported until another number is matched. This is intended
-for cases in which only state changes are reported, for example a thermometer
-that only reports the temperature when it changes.
+Report the last matching value. The metric is I<not> reset to C<NaN> at the end
+of an interval. It is continuously reported until another value is matched.
+This is intended for cases in which only state changes are reported, for
+example a thermometer that only reports the temperature when it changes.
=item B<CounterSet>
not use the matched subexpression, but simply count the number of matched
lines. Thus, you may use a regular expression without submatch in this case.
+B<GaugeInc> is reset to I<zero> after every read, unlike other B<Gauge*>
+metrics which are reset to C<NaN>.
+
=item B<Distribution>
Type to do calculations based on the distribution of values, primarily
point number, using L<strtod(3)>. The B<Counter*> and B<AbsoluteSet> types
interpret the submatch as an unsigned integer using L<strtoull(3)>. The
B<Derive*> types interpret the submatch as a signed integer using
-L<strtoll(3)>. B<CounterInc> and B<DeriveInc> do not use the submatch at all
-and it may be omitted in this case.
+L<strtoll(3)>. B<CounterInc>, B<DeriveInc> and B<GaugeInc> do not use the
+submatch at all and it may be omitted in this case.
+
+The B<Gauge*> types, unless noted otherwise, are reset to C<NaN> after being
+reported. In other words, B<GaugeAverage> reports the average of all values
+matched since the last metric was reported (or C<NaN> if there was no match).
=item B<Type> I<Type>
The default is to collect statistics for all domains and all their devices.
-Example:
+B<Note:> B<BlockDevice> and B<InterfaceDevice> options are related to
+corresponding B<*Format> options. Specifically, B<BlockDevice> filtering depends
+on B<BlockDeviceFormat> setting - if user wants to filter block devices by
+'target' name then B<BlockDeviceFormat> option has to be set to 'target' and
+B<BlockDevice> option must be set to a valid block device target
+name("/:hdb/"). Mixing formats and filter values from different worlds (i.e.,
+using 'target' name as B<BlockDevice> value with B<BlockDeviceFormat> set to
+'source') may lead to unexpected results (all devices filtered out or all
+visible, depending on the value of B<IgnoreSelected> option).
+Similarly, option B<InterfaceDevice> is related to B<InterfaceFormat> setting
+(i.e., when user wants to use MAC address as a filter then B<InterfaceFormat>
+has to be set to 'address' - using wrong type here may filter out all of the
+interfaces).
+
+B<Example 1:>
+
+Ignore all I<hdb> devices on any domain, but other block devices (eg. I<hda>)
+will be collected:
BlockDevice "/:hdb/"
IgnoreSelected "true"
+ BlockDeviceFormat "target"
-Ignore all I<hdb> devices on any domain, but other block devices (eg. I<hda>)
-will be collected.
+B<Example 2:>
+
+Collect metrics only for block device on 'baremetal0' domain when its
+'source' matches given path:
+
+ BlockDevice "baremetal0:/var/lib/libvirt/images/baremetal0.qcow2"
+ BlockDeviceFormat source
+
+As you can see it is possible to filter devices/interfaces using
+various formats - for block devices 'target' or 'source' name can be
+used. Interfaces can be filtered using 'name', 'address' or 'number'.
+
+B<Example 3:>
+
+Collect metrics only for domains 'baremetal0' and 'baremetal1' and
+ignore any other domain:
+
+ Domain "baremetal0"
+ Domain "baremetal1"
+
+It is possible to filter multiple block devices/domains/interfaces by
+adding multiple filtering entries in separate lines.
=item B<BlockDeviceFormat> B<target>|B<source>
Setting C<BlockDeviceFormat source> will cause the I<type instance> to be set
to C<var_lib_libvirt_images_image1.qcow2>.
+B<Note:> this option determines also what field will be used for
+filtering over block devices (filter value in B<BlockDevice>
+will be applied to target or source). More info about filtering
+block devices can be found in the description of B<BlockDevice>.
+
=item B<BlockDeviceFormatBasename> B<false>|B<true>
The B<BlockDeviceFormatBasename> controls whether the full path or the
B<number> means use the interface's number in guest.
+B<Note:> this option determines also what field will be used for
+filtering over interface device (filter value in B<InterfaceDevice>
+will be applied to name, address or number). More info about filtering
+interfaces can be found in the description of B<InterfaceDevice>.
+
=item B<PluginInstanceFormat> B<name|uuid|metadata|none>
When the virt plugin logs data, it sets the plugin_instance of the collected
=head1 IGNORELISTS
B<Ignorelists> are a generic framework to either ignore some metrics or report
-specific metircs only. Plugins usually provide one or more options to specify
+specific metrics only. Plugins usually provide one or more options to specify
the items (mounts points, devices, ...) and the boolean option
C<IgnoreSelected>.
projects / collectd.git / blobdiff