Call now: 252-767-6166  
Oracle Training Oracle Support Development Oracle Apps

 E-mail Us
 Oracle Articles
New Oracle Articles

 Oracle Training
 Oracle Tips

 Oracle Forum
 Class Catalog

 Remote DBA
 Oracle Tuning
 Emergency 911
 RAC Support
 Apps Support
 Oracle Support

 SQL Tuning

 Oracle UNIX
 Oracle Linux
 Remote s
 Remote plans
 Application Server

 Oracle Forms
 Oracle Portal
 App Upgrades
 SQL Server
 Oracle Concepts
 Software Support

 Remote S


 Consulting Staff
 Consulting Prices
 Help Wanted!


 Oracle Posters
 Oracle Books

 Oracle Scripts

Don Burleson Blog 







Detecting CPU bottlenecks in Windows

Oracle Database Tips by Donald BurlesonMay 27, 2015

Question:  My Windows server has been peaking at 100% utilization and I'm concerned that I have a processor bottleneck.  How do I tell when I have CPU enqueues in Windows?

100% utilization DOES NOT always indicate any bottleneck. It just means that the CPU is busy!  You ONLY have a CPU bottleneck when the runqueue exceeds cpu_count. 

You can see ?real? enqueues on CPU resources when the runqueue (r)column in vmstat exceeds the cpu_count parameter value, and you can also detect an overloaded CPU when you see the ?resmgr:cpu quantum? event in a top-5 timed event on a AWR or STATSPACK report. (only when the resource manager is being used)

In Windows, it's the "Processor Queue Length", and it's displayed in the system monitor and task manager.  Microsoft notes:

"Processor Queue Length (System) This is the instantaneous length of the processor queue in units of threads. All processors use a single queue in which threads wait for processor cycles.

After a processor is available for a thread waiting in the processor queue, the thread can be switched onto a processor for execution. A processor can execute only a single thread at a time. Note that faster CPUs can handle longer queue lengths than slower CPUs."

"The number of threads in the processor queue. Shows ready threads only, not threads that are running. Even multiprocessor computers have a single queue for processor time; thus, for multiprocessors, you need to divide this value by the number of processors servicing the workload. A sustained processor queue of less than two threads per processor is normally acceptable, depending upon the workload."



Oracle Training at Sea
oracle dba poster

Follow us on Twitter 
Oracle performance tuning software 
Oracle Linux poster


Burleson is the American Team

Note: This Oracle documentation was created as a support and Oracle training reference for use by our DBA performance tuning consulting professionals.  Feel free to ask questions on our Oracle forum.

Verify experience! Anyone considering using the services of an Oracle support expert should independently investigate their credentials and experience, and not rely on advertisements and self-proclaimed expertise. All legitimate Oracle experts publish their Oracle qualifications.

Errata?  Oracle technology is changing and we strive to update our BC Oracle support information.  If you find an error or have a suggestion for improving our content, we would appreciate your feedback.  Just  e-mail:  

and include the URL for the page.


Burleson Consulting

The Oracle of Database Support

Oracle Performance Tuning

Remote DBA Services


Copyright © 1996 -  2020

All rights reserved by Burleson

Oracle ® is the registered trademark of Oracle Corporation.