I just installed "sitedoc" after trying to keep notes about configuration changes manually for several months (which, of course, were always out of date or incomplete), so some automatism promised to help.
However, after installing the "sitedoc" module, enabling most of the option, and running the report for the first time, I got the following error:
Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 262144 bytes) in /var/www/drupal/includes/path.inc on line 62
It's not the first time I'm seeing errors like this on the site to-be-documented, so it's possibly not specific to the "sitedoc" module. The memory limit in php.ini is currently set to 64 MB and I'm not sure if it's sane to raise it even further. The reason for this might be the size of the site (>20k nodes), but basically this alone shouldn't be a problem for Drupal, I think.
To get "sitedoc" running, I unchecked all checkboxes in ./admin/settings/sitedoc and re-enabled the options one by one, starting at the top ("Include Basic Drupal information?"); checking one section more at a time and everytime running ./admin/build/sitedoc, I could get an almost complete report (approx. 800 kB). "sitedoc" finally died completely when enabling "Include URL Aliases?"; this resulted in a reproducable completely blank browser window without giving an error message.
I think, this might happen in a similar way on any other mid-size to large Drupal site (has "sitedoc" been run on drupal.org?). If this should not be specific for my site, I'd suggest to enable to tun the different reports completely separate, outputting the results in different sections/tabs of one main report. If there's another fix/workaround to get a full report in one run, this'd be nice, also ;)