`--backup=<directory>` option to preserve a copy of the original database. For
more details on this process see `notmuch-compact` man page.
+### Performance test suite
+
+Notmuch ships with a [[performance test suite|perf-test]] which uses a downloadable
+[[corpus]] of email.
+
### More information about this in the email archives:
* [Carl Worth](https://notmuchmail.org/pipermail/notmuch/2010/001105.html)