When a file system is journaled, some disk space is needed to keep the journal itself. The disk space that holds the actual data is referred to as the
<emphasis>data provider
</emphasis>, while the one that holds the journal is referred to as the
<emphasis>journal provider
</emphasis>. The data and journal providers need to be on different partitions when journaling an existing (non-empty) partition. When journaling a new partition, you have the option to use a single provider for both data and journal. In any case, the
<command>gjournal
</command> command combines both providers to create the final journaled file system. For example:
