To improve performance, you can use a cache service for the SelectList widget and ComboBox widgets.
When the client requests a list from server, the server looks in the cache for the file content specified by URLforList. If the cache does not contain the value, the server reads the file by its URL, and then puts its content in the cache. Then the server sends the file content to the client browser.
To use the cache
Set the value of URLforList of selectList or comboBox widget by using the toolkit.