and the sensible setting is a multiple of the B<ReadThreads> value.
If you are not sure, just use the default setting.
+=item B<ExtraStats> B<string>
+
+Enable extra statistics. This allows the plugin to reported more detailed
+statistics about the behaviour of Virtual Machines. The argument is a
+space-separated list of selectors. Currently only B<disk> is supported.
+
=back
=head2 Plugin C<vmem>