LabWindows CVI 8.5 needs up to 100% CPU usage without active application

[kakrieg]

Hello,

when  I launch the application LabWindows/CVI 8.5 the CPU usage ist jumping up to 100 %. The CPU usage stays at this level, even if no action is done.

Checking the taskmanager the process cvi.exe is consuming so much cpu usage. The memory stays at ap. 35MB.

There's no difference in behavior of the CPU usage when i launch LabWindows as first program or during the normal work.

Launching LabWindows CVI on other Machines I had no problems and the CPU usage stays below 10 per cent. 

I hope you have an idea.

My system:

Windows XP SP2 (network pc)

1GB RAM

2.4 GHz with 25GB free disk space. 

Many Thanks

kakrieg 

[RobertoBozzolo]

CPU usage is very affected by CVI sleep policy: in Options >> Environment panel you can see the Advanced box containing CVI environment sleep policy field: setting it to "Do not sleep" makes CPU usage to jump to 1005 since CVI checks the queues at the maximum possible rate in order to catch user and program event as fast as possible. On my machine, simply lowering this value to "Sleep some" lowers CPU usage down to 25-27%. This can be seen interactively in the IDE and can be set and manipulated at runtime with SetSleepPolicy ()  command, so that you can tailor processor usage depending on the state of your application. Remember that this parameter is thread specific, that is you must call the function in each thread for which you want to change this behaviour