Refresh user summaries? How often?

I have a plugin that loads data into user summaries. However, this data won’t get updated unless I run:

UserSummarySerializer.cache.clear

Is the best way forward then making a job to run this hourly so that the summary is still fresh? Because doing this would re-trigger my add_to_serializer which adds the relevant data to the user summary. But does doing it hourly create undue stress, if there are many, many users?