Skip navigation.
Home
The QNX Community Portal

View topic - System time is running very fast

System time is running very fast

For discussion of realtime and/or embedded programming.

System time is running very fast

Postby Sherlock1982 » Thu Dec 02, 2010 10:37 am

I'm using QNX 6.4.1 on ARM board. qconn shows 100% cpu usage. When I use "date" command I see that time running about 4-10 seconds per real second and isn't regular.

When I slay some applications and cpu usage lowers I see that time become normal again.
How it can be and how system manages CLOCK_REALTIME ?
Sherlock1982
New Member
 
Posts: 1
Joined: Thu Dec 02, 2010 10:32 am

RE: System time is running very fast

Postby maschoen » Thu Dec 02, 2010 7:12 pm

CLOCK_REALTIME is set by a timer interrupt. It sounds like you have other interrupt handlers that are hogging the cpu. I don't know about ARM but on X86 you can pick the interrupt that you want to have the highest priority. Of course interrupt handlers and programs can turn off interrupts which will also cause this problem.
maschoen
QNX Master
 
Posts: 2640
Joined: Wed Jun 25, 2003 5:18 pm


Return to Realtime and Embedded

Who is online

Users browsing this forum: No registered users and 2 guests