-<para>Note that the Callgrind Format is more compact than the Massif Format,
- and contains the full data : there is no filtering during file production,
- filtering is done by visualisers such as kcachegrind. kcachegrind is
- particularly easy to use to analyse big xtree data containing multiple
- events counts or resources consumption.</para>
+<para>Note that for equivalent information, the Callgrind Format is more compact
+ than the Massif Format. However, the Callgrind Format always contains the
+ full data: there is no filtering done during file production, filtering is
+ done by visualisers such as kcachegrind. kcachegrind is particularly easy to
+ use to analyse big xtree data containing multiple events counts or resources
+ consumption. The Massif Format (optionally) only contains a part of the data.
+ For example, the Massif tool might filter some of the data, according to the
+ <option>--threshold</option> option.
<para>To clarify the xtree concept, the below gives several extracts of
the output produced by the following commands: