Latency-CPU1 not working

Dear All,

I am struggling to reach a max jitter value below 30k ns for last couple of weeks.

I am using a dual core CPU and 41 mother board, 4 GB ram.

BIOS setting are attached in photo.

I have set isolcpu=1 and upadte-grub is run.

But by using "TOP" command when I notice the CPU usage, CPU1 is 0 i.e not in use. This is something really not expected neighther I could found the reason/solution.

Please help. As I am not a computer guy, it is beyond my expertise.

Thanks in advance.

Other photos of BIOS and screenshots.

Cpu usage screen shots

rajsekhar wrote:

I have set isolcpu=1 and upadte-grub is run.

But by using "TOP" command when I notice the CPU usage, CPU1 is 0 i.e not in use. This is something really not expected neighther I could found the reason/solution.

Isolcpu = isolate cpu = do not use cpu
So it is expected.
IRQ stuff you have in GRUB do not do much on new-ish systems.
Anyway you look at it, 30K is a very good latency if it does not spike during use.

Well, Max jitter is spiking beyond 30k..upto 50~55k with 5 glxgears..how to control? any solution?

Yes, stop chasing that, go make the machine move and enjoy watching it.
It is usable, it should work, might have limited velocity, everything else should be fine.

Understand..ok

But is there any risk of missing step output?? That is the point of concern..I can adjust with the limited velocity for this case.

If you get latency warnings when using LinuxCNC, set the base period in the ini file higher, test again.

Ḥello..everyone..I take the opportunity to inform the final result of the latency war as follows:

• I finally ended with RT-Preempt kernel, RTAI does not support additional parallel ports which are available here in INDIA.
• Using video card RADEON HD 7300 1GB. this actually solved the issue.
• I finally not using any CPU isolation and also not using multitasking the PC either.
• Latency is under 25k ns mostly.