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>
=item B<TypeInstance> I<Regex>
+=item B<MetaData> I<String> I<Regex>
+
Match values where the given regular expressions match the various fields of
the identifier of a value. If multiple regular expressions are given, B<all>
regexen must match for a value to match.
=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