On Sun, Aug 24, 2014 at 9:26 AM, Paul Robert Marino <[log in to unmask]> wrote: > That said I've run hundreds of mission critical systems many accurate to within 5 > milliseconds on the standard kernel with proper tuning and a stripped > down OS install for nearly a decade and Ive never had an issue. The standard Linux kernel shipped by most distributions is actually quite effective in applications that require millisecond level scheduling precision. Paul's experience confirms this. If the need for smaller interrupt and scheduling latency arises, the stock kernel source allows you to generate a soft real-time kernel by choosing the "Preemptible Kernel" (PREEMPTDESKTOP) during kernel configuration and compilation. What the standard kernel source doesn't provide is reliable and consistent sub-millisecond scheduling. Applying the PREEMPT_RT patch generates what can for the most part be considered a hard RTOS kernel. For the most part in 99% of applications the standard kernel will suffice. Without knowing what Lee's application is, it is impossible to determine if he really needs a soft or hard real-time kernel. Brandon Vincent