The Host CPU Usage (Percent) alert indicates an unusually high amount of CPU usage by the VMWare or Hyper-V host server hosting the virtual machine on which the monitored SQL Server instance resides. The percentage of host server processor usage is listed under the control. A high host server percentage could indicate a large number of active client sessions. This alert is enabled by default and is available only on instances hosted on virtual machines enabled for VM monitoring.
Reduce your host CPU usage
Consistently high host server processor usage could indicate the need to:
- Reduce the number of SQL re-compilations as they are CPU intensive. There are many reasons that an object such as a stored procedure is recompiled and you can remove most of these reasons by careful coding.
- Make sure that all T-SQL statements (whether in a stored procedure, trigger or ad hoc statement) that reference objects fully qualify the object referenced.
For example: SELECT * FROM Northwind.dbo Employees is a fully-qualified object reference whereas SELECT * FROM Employees is a poorly-qualified object. You can reuse the execution plans of fully-qualified objects "as is," whereas plans where you either cannot reuse the not fully-qualified objects or, if they are reused, then they are subject to a highly restrictive COMPILE lock while SQL Server determines if all of the objects referenced in the T-SQL code have the same owners as the execution plan currently in cache. Both of these situations consume a significant amount of CPU time.