This policy setting allows you to specify the maximum number of minutes the system will spend processing an individual query. ...

This policy setting allows you to specify the maximum number of minutes the system will spend processing an individual query.  When the interval is exceeded, the processing is aborted and the query is marked as failed.  The query will then be retried later.  Several bulk operations (especially queries) can take a significant amount of time before all results are retrieved and processed.  During this time no other operation can be processed.If you enable this policy setting, you may specify the maximum number of minutes the system will spend processing an individual query.If you disable or do not configure this policy setting, a default value of 20 minutes will be used.