Symptoms : SQL is running slow

Impact : Medium

Slow SQL responses will degrade the user experience, resulting in poor efficiency of your organization’s operations.

Expected behavior :

There are no suggested metrics for CPU utilization. The figures will vary based on levels of user activity, time of day etc. Business Intelligence (BI) applications will typically load the CPU by 20-30 per cent above other applications. In addition, load from non-SQL activities can significantly increase overall utilization level.

Possible causes

Long system tasks   Priority : Medium
Unusual levels of CPU load activities may be coming from external operations (anti-virus scans, backups, restores etc from networked data stores)
Recommended action :
Identify the source of the load (using built-in OS tools such as PerfMon) and if it is recurrent, try to reschedule to a time of low user demand.

Long SQL tasks  Priority : Medium
SQL Processes started to load CPU due to long tasks performed such as :

  • accessing data where indexes are missing or corrupt (causes long loops)
  • pulling large volumes of data (results in many threads or long loops)
  • coding problems (inefficient organization, missing indexes causing many threads or long loops


Recommended action :
See our recommendations regarding deadlocks here and free memory here.

Background

>CPU utilization measures the load of all the tasks that are being performed by the server. This depends largely on the type of operation, for example Business Intelligence applications typically take over 80% of CPU capacity, compared SQL database application, where CPU usage below 70% is considered normal. CPU usage above this number means degradation in user response times..