RefreshUserImpactJob is a job that refreshes user impact data for the purpose of displaying those at Special:Homepage and Special:Impact, see https://www.mediawiki.org/wiki/Growth/Positive_reinforcement for project details.
Filling this task as an umbrella task for all RefreshUserImpactJob-related tasks that might be explained by the "too many descriptors" root cause, to ensure the discussion around the root cause is centralized and to ensure individual symptomps (error messages) are logged individually, to make them findable.
The job makes a lot of AQS requests and other file descriptor-consuming actions (such as, database connections), to fetch all the necessary data that can be precalculated and cached in growthexperiments_user_impact. Unfortunately, the job seems to be consuming too many file descriptors, and either the job or a used library might be forgetting to close something.
Goal of this task is to determine the root cause of the problem.