How to disable multitasking in Win XP?

Hi,

Can anyone tell how to stop Win XP from switching out an application (i.e. giving nearly full CPU bandwidth to the application)? Basically disabling multitasking.

We are using .NET 2005 to write a program to send/receive data through the serial port and want to achieve full transmission speed with no gaps. Oscilloscope shows a gap which is inexplicable by looking at the coding so must be coming from Windows preemptive switching out of our application.

Thank you in advance.

 

I don't think you're ever going to fully stop Windows from being a multi-tasking OS - that sort of thing is built in at an architectural level.

What Windows does use however is a pre-emptive Multi-task scheduler - a tried and tested approach which means that a thread/process cannot typically be pre-empted (kicked off the CPU) by another process with a lower priority.

The easiest solution I think you're going to find to test this is to start the application and then manually set the process to a High priority in the Task manager. Right Click the process and then 'Set Priority'.

You're never going to stop the base OS kicking you off when it has something it deems more important to do though.

 

Hello QuickSilver,

Thank you for your reply! Someone earlier had expressed something similar to the above although he was not sure.
Your emphatic reply helps since now I won't even try to hunt for such a solution. Also, it's good to know that at least a lower priority job will not displace a higher priority application.

I hadn't gotten any replies on this thread so I had stopped checking this email; so the delay.

Best Regards,

 

I was also about to suggest the same, set the task as a high priority task (or program it to set itself as a high priority task) - and if your problem is specific to one computer, I suggest you remove any programs or services that could possibly get in the way - this should cut down the interruption by quite a bit!

hope this helps.

 

Thank you! That's also a good idea.

All-
Btw, changing the priority did not help one bit (the delays on the serial line seen on the o'scope are still the same). That almost concludes that it is not an OS issue (otherwise it would have made at least some difference).

We are now looking into hardware drivers that might be causing the problem but I think the original question on this thread has been well answered. Thanks to everyone who gave suggestions!