Email router and SQL query performance issue

Hi All,

For CRM 2013 on-premise version, we have configured email router to send email notification as majority of times user's outlook is not open and workflow was not able to send email through outlook

This creates performance related issue - it started executing following query so frequently which generates high wait time on server.

SELECT top 5 "email0".Subject as "subject" ,
"email0".Description as "description" ,
.... FROM Email as "email0" (NOLOCK)
...

Is there any alternate/solution to reduce this wait or an alternate to configure email router to reduce number of execution and logical read for the query mentioned.

Regards,

Patel