Merge remote-tracking branch 'github/pr/1922'

diff --combined src/collectd.conf.pod
index ec2a0c5,127d518..4f95425
--- 1/src/collectd.conf.pod
--- 2/src/collectd.conf.pod
+++ b/src/collectd.conf.pod
@@@ -7818,32 -7818,6 +7818,32 @@@ If set to B<true>, append the name of t
  identifier. If set to B<false> (the default), this is only done when there is
  more than one DS.
  
 +=item B<DropDuplicateFields> B<false>|B<true>
 +
 +If set to B<true>, detect and remove duplicate components in Graphite metric
 +names. For example, the metric name  C<host.load.load.shortterm> will
 +be shortened to C<host.load.shortterm>.
 +
 +=back
 +
 +=head2 Plugin C<write_log>
 +
 +The C<write_log> plugin writes metrics as INFO log messages.
 +
 +This plugin supports two output formats: I<Graphite> and I<JSON>.
 +
 +Synopsis:
 +
 + <Plugin write_log>
 +   Format Graphite
 + </Plugin>
 +
 +=over 4
 +
 +=item B<Format> I<Format>
 +
 +The output format to use. Can be one of C<Graphite> or C<JSON>.
 +
  =back
  
  =head2 Plugin C<write_tsdb>
@@@ -9407,10 -9381,6 +9407,10 @@@ Available options
  
  =item B<TypeInstance> I<Regex> I<Replacement>
  
 +=item B<MetaData> I<String> I<Regex> I<Replacement>
 +
 +=item B<DeleteMetaData> I<String> I<Regex>
 +
  Match the appropriate field with the given regular expression I<Regex>. If the
  regular expression matches, that part that matches is replaced with
  I<Replacement>. If multiple places of the input buffer match a given regular
@@@ -9449,9 -9419,37 +9449,37 @@@ Available options
  
  =item B<MetaData> I<String> I<String>
  
- Set the appropriate field to the given string. The strings for plugin instance
- and type instance may be empty, the strings for host and plugin may not be
- empty. It's currently not possible to set the type of a value this way.
+ Set the appropriate field to the given string. The strings for plugin instance,
+ type instance, and meta data may be empty, the strings for host and plugin may
+ not be empty. It's currently not possible to set the type of a value this way.
+ 
+ The following placeholders will be replaced by an appropriate value:
+ 
+ =over 4
+ 
+ =item B<%{host}>
+ 
+ =item B<%{plugin}>
+ 
+ =item B<%{plugin_instance}>
+ 
+ =item B<%{type}>
+ 
+ =item B<%{type_instance}>
+ 
+ These placeholders are replaced by the identifier field of the same name.
+ 
+ =item B<%{meta:>I<name>B<}>
+ 
+ These placeholders are replaced by the meta data value with the given name.
+ 
+ =back
+ 
+ Please note that these placeholders are B<case sensitive>!
+ 
+ =item B<DeleteMetaData> I<String>
+ 
+ Delete the named meta data field.
  
  =back