Improving database and Domino® Directory performance

By default, the Domino® Directory uses two database performance properties -- Document table bitmap optimization and Don't maintain unread marks -- to improve performance. The following NOTES.INI settings can affect database and Domino® Directory performance.

NSF_Buffer_Pool_Size

This NOTES.INI setting sets the size of the NSF buffer pool, a section of memory used for buffering I/O transfers between the NSF and NIF subsystems and disk storage. The number of server partitions, users, size and number of views, and number of databases all affect how you should set the buffer pool specification. The default value (determined automatically by the server) is usually sufficient, but if Database Statistics indicate more memory is needed, increase the value a few megabytes at a time. You can use a performance monitor to find out if a larger value is causing too much swapping or paging. (NSF_Buffer_Pool_Size sets the buffer pool size in bytes; NSF_Buffer_Pool_Size_MB sets the size in megabytes.)

NSF_DbCache_Maxentries

This NOTES.INI setting sets the maximum number of databases stored in the database cache (if enabled). For short intervals, Domino® stores up to 1.5 times the number entered for this setting. Increasing the maximum number of databases improves performance but requires more memory.

Improving performance for users accessing the Web using the Web Navigator

There are several ways to improve performance:

  • Speed up your access to Web pages by speeding up your server connection to the Internet. Contact your Internet Service Provider to find out what options you have.
  • Improve database performance by managing your database with the Purge and Refresh agents or any other agents you may create for the database.
  • Manage the number of users retrieving pages in the Web Navigator database by setting the maximum number of concurrent retrievals (the number of Web pages the server retrieves at the same time). The default maximum number of concurrent retrievals is 25. The number of concurrent retrievals that your server allows depends on your specific system environment.

Show DBS command

The Show DBS command is a tool for monitoring the performance of a database. This command returns the following information:

  • Refs -- The number of times the database has been opened (the DBHANDLE count for the database).
  • Mod -- Whether the database has been modified, but not yet flushed to disk.
  • FDs -- The number of file descriptors currently being used for the database.
  • LockWaits -- The number of times a user has had to wait for a lock on the database (read or write).
  • AvgWait -- The average wait time in milliseconds for each wait.
  • #Waiters -- The number of waiters currently on the database lock. (This number changes rapidly.)
  • MaxWaiters -- The maximum number of waiters ever on the database lock.
Note: To display LockWaits and AvgWait values, you must temporarily add the setting COLLECT_DB_LOCK_WAITS=1 to the server's NOTES.INI file. Because this setting consumes server resources, remove it after you view Show DBS statistics.