1. Don't have too many views - each time you change/add a document Notes will need to update every appropriate view.
2. Keep views simple - more columns means more calculation. It gets worse if the columns are sorted and worse still if the columns are categorized.
3. Don't use @Today or @Now in selection formulas - the views will never be up to date and the server will be forever recalculating them. If you need to use today's date in a selection formula then have a background macro running each day to set an environment variable in the server's notes.ini and reference this.
4. If you want to display compound information in a view column from multiple fields then calculate it in a hidden document field. The column should then reference this single field rather than carrying out the calculation.
5. To avoid the @DBColumns/@DBLookups used to generate keyword lists, etc.,
being generated at read time use something like:
@If(@IsDocBeingLoaded & !@IsNewDoc; @Unavailable; @DbColumn(""; ""; "By _Category (Main View)"))
6. Use column numbers not field names for lookups
7. If you are doing lots of lookups to multiple columns in a single view then append all of the data in a single column with a unique delimiter string and do a single lookup. The value returned can then be parsed with @Left/@Right/@Mid or @Explode to give you the separate field values.
8. Put 64 Mb of RAM in the server and push the buffer pool sizes to their limits. This is documented in the Knowledge Base.
An IBM Redbook is also available: Performance Considerations for Domino Applications.
A developerWorks article is also available: Troubleshooting Application Performance