Improve company productivity with a Business Account.Sign Up

x
?
Solved

Why is nmon showing 8 CPU when I have 4 physical CPU and no partitions?

Posted on 2007-11-13
4
Medium Priority
?
936 Views
Last Modified: 2013-11-17
nmon when run on AIX 5.x is showing 8 CPU on a 4 way non partitioned box.  Our 8 way is showing CPU of 16 when viewed with nmon.  Can anyone explain to me why this is?
0
Comment
Question by:Angela_Wilcox
  • 2
4 Comments
 
LVL 14

Expert Comment

by:sjm_ee
ID: 20278451
Is SMT on? Run "smtctl" to see if it is. What do the first 40 or so lines of "prtconf" say?
0
 
LVL 13

Expert Comment

by:dfke
ID: 20279291
Yes, this is due to the SMT feature of the POWER5 chip, where each CPU (core) runs two processes at the same time.

0
 

Author Comment

by:Angela_Wilcox
ID: 20288386
Could it also be a result of our 64 bit upgrade - which I did not know we had done??
0
 
LVL 13

Accepted Solution

by:
dfke earned 1200 total points
ID: 20297863
No it's really due to the SMT feature on the chip.

SMT, or Simultaneous Multi-threading is a hyperthreading design. Somewhat like Intel's Pentium 4 HT. Which also doubles the amount of cpus in Windows. It makes each core capable of running two threads at once.  The OS "sees" the SMT feature as a logical cpu apart from the physical cpu or core if you will.

0

Featured Post

Upgrade your Question Security!

Your question, your audience. Choose who sees your identity—and your question—with question security.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

I promised to write further about my project, and here I am.  First, I needed to setup the Primary Server.  You can read how in this article: Setup FreeBSD Server with full HDD encryption (http://www.experts-exchange.com/OS/Unix/BSD/FreeBSD/A_3660-S…
FreeBSD on EC2 FreeBSD (https://www.freebsd.org) is a robust Unix-like operating system that has been around for many years. FreeBSD is available on Amazon EC2 through Amazon Machine Images (AMIs) provided by FreeBSD developer and security office…
This video shows how to set up a shell script to accept a positional parameter when called, pass that to a SQL script, accept the output from the statement back and then manipulate it in the Shell.
In a previous video, we went over how to export a DynamoDB table into Amazon S3.  In this video, we show how to load the export from S3 into a DynamoDB table.

585 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question