Use the new EXCEPTION_CATEGORY field of the Apex Unexpected Exception event type of the EventLogFile object. The EXCEPTION_CATEGORY field provides a breakdown of unhandled exceptions based on the type. For example, the LimitException exception type is split into subcategories that indicate if you exceeded the total heap size or CPU time.
Where: This change applies to Lightning Experience and Salesforce Classic in Enterprise, Unlimited, Developer, and Performance editions.
Who: This change is available to customers who purchased Salesforce Shield or Salesforce Event Monitoring add-on subscriptions.
Get the Category of the Apex Unexpected Exception Event (salesforce.com)