photon preempts interrupts

I have a hardware interrupt (number 5) being generated from an ISA
custom board periodically, 10 kHz. A resource manager is running a
thread to handle the interrupt via interruptattachevent. The processor
is a 266MHz AMD. In the Photon window environment, it gets preempted
almost every 49th interrupt and more thereafter. It wouldn’t be so bad
if it was preempted for less than 10 microseconds but it last more than
50 microseconds. This doesn’t happen in textmode.
What is it and how can I control it?

“S. Ribail” <saul.ribail@lmco.com> wrote in message
news:3BF292F9.AC03C629@lmco.com

I have a hardware interrupt (number 5) being generated from an ISA
custom board periodically, 10 kHz. A resource manager is running a
thread to handle the interrupt via interruptattachevent. The processor
is a 266MHz AMD. In the Photon window environment, it gets preempted
almost every 49th interrupt and more thereafter. It wouldn’t be so bad
if it was preempted for less than 10 microseconds but it last more than
50 microseconds. This doesn’t happen in textmode.

Increase the priority of your process above that of Photon application.

What is it and how can I control it?