node_access rebuild in a confusing place

Split off from: http://drupal.org/node/75395

Kjartan said:

However, going back to the original patches and not the latest fix which should go in. Does the node access menu item really have to be a menu item? The way it is coded now this query will be run on pretty much every page hit. Wouldn't it better to move it out of the menu and instead have it be an additional option on the node settings page? This doesn't strike me as a feature that needs its own menu item as you should only have to run it if something has really gone wrong. Burry it somewhere with lots of warning text to never ever run this unless you have good reason to. This way it a) doesn't have a performance hit unless the user is on a specific page (menu is slow enough as it is), b) users might not get in trouble by playing around with menu items.

Also I wonder if this needs to work like search-index and be able to run in mutiple cron runs. Anyone got any data on how many nodes/node_access modules you can have before a rebuilding of the node_access table can't happen in one run?

The other thing is that in general the node access stuff can very easilly get you in all sorts of trouble, all you need is one poorly coded module that does the wrong thing. To combat this there needs to be more documentation, both for developers so they what the Right Way is, and for end users so when they download a node_access enabled module they some documentation to get them out of trouble.