-## usage
-
-Here are descriptions of all the supported parameters to the `aggregate`
-directive:
-
-* `name` - A name for the feed. Each feed must have a unique name.
- Required.
-* `url` - The url to the web page for the blog that's being aggregated.
- Required.
-* `dir` - The directory in the wiki where pages should be saved. Optional,
- if not specified, the directory is based on the name of the feed.
-* `feedurl` - The url to the feed. Optional, if it's not specified ikiwiki
- will look for feeds on the `url`. RSS and atom feeds are supported.
-* `updateinterval` - How often to check for new posts, in minutes. Default
- is 15 minutes.
-* `expireage` - Expire old items from this blog if they are older than
- a specified number of days. Default is to never expire on age.
-* `expirecount` - Expire old items from this blog if there are more than
- the specified number total. Oldest items will be expired first. Default
- is to never expire on count.
-* `tag` - A tag to tag each post from the blog with. A good tag to use is
- the name of the blog. Can be repeated multiple times. The [[tag]] plugin
- must be enabled for this to work.
-
-Note that even if you are using subversion or another revision control
-system, pages created by aggregation will *not* be checked into revision
-control.
-
-This plugin is not enabled by default.
-
-[[tag type/useful]]
+Alternatively, you can allow `ikiwiki.cgi` to trigger the aggregation. You
+should only need this if for some reason you cannot use cron, and instead
+want to use a service such as [WebCron](http://webcron.org). To enable
+this, turn on `aggregate_webtrigger` in your setup file. The url to
+visit is `http://whatever/ikiwiki.cgi?do=aggregate_webtrigger`. Anyone
+can visit the url to trigger an aggregation run, but it will only check
+each feed if its `updateinterval` has passed.
+
+## internal pages and `aggregateinternal`
+
+This plugin creates a page for each aggregated item.
+
+If the `aggregateinternal` option is enabled in the setup file (which is
+recommended), aggregated pages are stored in the source directory with a
+"._aggregated" extension. These pages cannot be edited by web users, and
+do not generate first-class wiki pages. They can still be inlined into a
+blog, but you have to use `internal` in [[PageSpecs|IkiWiki/PageSpec]],
+like `internal(blog/*)`.
+
+For backward compatibility, the default is that these pages have the
+".html" extension, and are first-class wiki pages -- each one generates
+a separate HTML page in the output, and they can even be edited.
+
+That turns out to not be ideal for aggregated content, because publishing
+files for each of those pages is a waste of disk space and CPU, and you
+probably don't want to allow them to be edited. So, there is an alternative
+method that can be used (and is recommended), turned on by the
+`aggregateinternal` option in the setup file.
+
+If you are already using aggregate and want to enable `aggregateinternal`,
+you should follow this process:
+
+1. Update all [[PageSpecs|ikiwiki/PageSpec]] that refer to the aggregated
+ pages -- such as those in inlines. Put "internal()" around globs
+ in those PageSpecs. For example, if the PageSpec was `foo/*`, it should
+ be changed to `internal(foo/*)`. This has to be done because internal
+ pages are not matched by regular globs.
+2. Turn on `aggregateinternal` in the setup file.
+3. Use [[ikiwiki-transition]] to rename all existing aggregated `.html`
+ files in the srcdir. The command to run is
+ `ikiwiki-transition aggregateinternal $setupfile`,
+4. Refresh the wiki. (`ikiwiki -setup your.setup -refresh`)