For the best calendaring experience, a user's calendar files should not exceed 8 - 10mb in size. However, if a calendar has a number of recurring events -- several daily or weekly recurring events especially -- keeping those calendar files smaller, 8mb or less, may be warranted to ensure that the server runs at an optimal level. TO assist with keeping these files at a manageable size, we strongly recommend the use of Calendar Auto-Clean to keep past calendar events from cluttering up calendar views and to keep calendar JSON files from exceeding the recommended size limit.
System Administrators can set the default Calendar Auto-Clean setting for a domain within the domain's configuration settings. The User Defaults template can then set a user's Calendar Auto-Clean setting to use that Domain Default or set it to Never, 3, 6, 9, 12, 18 or 24 months. Domain Administrators may also modify this setting per user in the user's configuration options.
Please note that although System and Domain Administrators can enable Calendar Auto-Clean for a user by default, the user may still adjust the setting or turn it off within their Calendar Settings. Therefore, it is important to monitor users' calendar files periodically and contact users that are exceeding the recommended limit.