What I have noticed is that the cache trimming never removes the last cached document, but otherwise it works as expected. I don't know if this is related to IIS or not.

Christian Davén  that I know , cache trimming never remove  the last cached if document are opened in viewer.

we set below setting

<add key="DocumentUltimateWeb:CacheLocation" value="\\Pavan\Publish_webSite\View_scan_doc\App_Data\DocumentCache"/>

locally its trimming cache but  when we publish code into IIS, the cache deletion does not seem to be functioning as expected.

Cem Alacayir kindly Reply asap.

This happens because when an ASP.NET application is hosted on IIS, it's life is controlled by IIS. For example, IIS can kill/recycle the application pool process when the site is idle.

By default, a web application will not be started until the first user hits your site. Even more, there are some events that will bring your web application down after some time (idle Timeout and different app pool recycling events). In these cases, as the DocumentCache's recurring tasks runs inside the web application, these tasks will not be enqueued, and enqueued jobs will not be processed.

This is particularly true for smaller sites, as there may be long periods of user inactivity. However this can be changed with IIS settings. You can ensure that your web app instance is always running to guarantee the in-time background job processing.

References:

Hi