The portal's cache is completely cleared every 15 minutes, and the cache will not be available for subsequent page views.
Also, the cache is cleared for the records that make up the portal.
By not being able to use the cache, there will be a lot of waiting time before the page is displayed.
Also, since users do not use the portal all the time, but use it whenever necessary, the cache is cleared in 15 minutes, which means that there are few opportunities to use the cache, leading to poor performance.

・The cache of the record that composes the portal should be a differential capture.
For the records that make up the portal, do not clear the cache if there are no differences, but clear the cache only if there are differences.
This will prevent performance degradation during screen display.

・Cached information should be reloaded instead of cleared every 15 minutes.
Instead of clearing the cache completely every 15 minutes, only clear the cache generated before 15 minutes.
This will increase the chance of using the cache for screens that users use regularly and prevent performance degradation.