DATABASE MANAGEMENT
Update
Update is loaded at server startup by default and runs continually, checking its work queue for views and folders that require updating. The indexer uses modest system resources by waiting five seconds between each database update operation that is performs.
The Update task performs three different updating tasks:
Update maintains two queues of work -- an immediate queue and a deferred queue. Other server components, such as the router and replicator, post requests to the updater when changes are made to databases. Some requests are posted as deferred and some as immediate.
This table lists how full-text index updates are performed according the update frequency:
When Update encounters a corrupted view index or full-text index, it rebuilds the view index or full-text index in an attempt to correct the problem. Update deletes the view index or full-text index and rebuilds it.
Note The Update task spawns a directory indexer thread. The directory indexer runs at one-minute intervals and is dedicated to keeping IBM® Lotus® Domino® Directory view indexes up-to-date so that any changes to the directory are usable as soon as possible. The directory indexer runs against any local or remote Domino Directory or Extended Directory Catalog that a server uses for directory services. The task of updating the Domino Directory view indexes does not lock the views, and you should be able to create new server sessions while this task is running.
To improve view-indexing performance, and if your server has adequate CPU power, you can run multiple Update tasks.
Managing the update task and its use of system resources
The indexer is able to keep up with the update rate in the server's default configuration if the server has a low update rate, that is, if few changes are made to databases on the server. If a server has a high update rate due to heavy application database use, a large number of mail users, or a large volume of mail, the default resource usage configuration can cause the updater queues to become large. To determine whether the updater queues are large, examine the queue length statistics that are available in Lotus Domino 7 and more recent. If you determine that the update queues are too large, determine a methodology for performing updates on that server. Long queues typically indicate that views and full-text indexes are not up-to-date.
Here are some sample scenarios and practices that you may want to use as well as the steps to implement them.
To allow frequent full-text indexing on only a small number of databases, and to prevent other databases from being full-text indexed, disable full -text indexing in the Updater and then add Program documents to schedule Updall to run, for example, every half hour (30 minutes). To disable full-text indexing in the Updater, enter this variable, UPDATE_DISABLE_FULLTEXT=1, in the server's NOTES.INI file.
You can prevent performing any updates at all, and just allow view opens to perform the view updates automatically. To prevent updates, edit the NOTES.INI variable by removing the update string.
If a system has adequate system resources to perform updates, you can run multiple Update tasks. To do so, edit the variable, ServerTasks, in the NOTES.INI file and add a second Update task.
You can adjust the controls that determine whether a modified view is actually updated or not. The database and view must still be opened, but if these thresholds are not reached, the view is not updated.
Updall
Updall is similar to Update, but it doesn't run continually or work from a queue; instead you run Updall as needed. You can specify options when you run Updall, but without them Updall updates any view indexes or full-text search indexes on the server that need updating. To save disk space, Updall also purges deletion stubs from databases and discards view indexes for views that have been unused for 45 days, unless the database designer has specified different criteria for discarding view indexes. Use the NOTES.INI setting Default_Index_Lifetime_Days to change when Updall discards unused view indexes.
Like Update, Updall rebuilds all corrupted view indexes and full-text search indexes that it encounters.
By default Updall is included in the NOTES.INI setting ServerTasksAt2, so it runs daily at 2 AM. Running Updall daily helps save disk space by purging deletion stubs and discarding unused view indexes. It also ensures that all full-text search indexes that are set for daily updates are updated.
Note When views are being rebuilt - either through the Designer or Updall tasks - all new server sessions that are attempted once the rebuild process has started are locked out. Therefore, it is recommended that changes to master templates, as well as complete view rebuilds, be scheduled for late at night, when users are far less likely to require access to the server.
The following table compares the characteristics of Update and Updall. For Updall, the table describes default characteristics. You can also modify some of these characteristics with Updall options.