ps bug

QNX USERS QNX6 - OS
1

I noticed that with QNX 6.3.2 the ps command:

“ps -e -o pcpu,args”

Only ever outputs 0 for the cpu percentage (I have processes using 1% or higher).

Is there any other command (that will run to completion) and give me the cpu percentages of all processes running?

2

No answer to your question, but I did confirm the bug still exists in 6.4.1. Looking at the code itself, it’s a simple integer division problem when finding the percent. They do ((x/y)*100). Since x/y is always between 0 and 1 (except for 100% usage) and the variables are integers the x/y is always rounded down to 0 before the multiplication. It’s a simple fix so if you register at foundry27 and get access to the code you can fix it yourself. Anyway, I’ll post a bug to QNX so it will hopefully be fixed in a future release.

In the meantime there are a few options I know of, none of which satisfy all your stated requirements, that may be useful.
top -i 1

  • top displays the 10 biggest CPU users, by using “-i 1” top will run to completion after 1 iteration

pidin times

  • will display all processes and run to completion showing CPU usage, but displays usage as time rather than percentage

From what I’ve been told, all these utilities do a fairly poor job of measuring actual CPU usage and you should really try to use something like the System Profiler to get more accurate results.

Hope that helps
Steve

3

Thanks allot steve.

I do not seem to have top on my system though 0_o QNX version 6.3.2.

4

David,

Try ‘hogs -n -%1 -s#’ where # is the number of seconds you want to sample the CPU usage at. The %1 tells Hogs not to bother displaying any process that uses less than 1% of the CPU in the sample period.

Tim

5

There is a 3rd-party utility called spin. It works fine…