| |
| choice |
| prompt "Preemption Model" |
| default PREEMPT_NONE |
| |
| config PREEMPT_NONE |
| bool "No Forced Preemption (Server)" |
| help |
| This is the traditional Linux preemption model, geared towards |
| throughput. It will still provide good latencies most of the |
| time, but there are no guarantees and occasional longer delays |
| are possible. |
| |
| Select this option if you are building a kernel for a server or |
| scientific/computation system, or if you want to maximize the |
| raw processing power of the kernel, irrespective of scheduling |
| latencies. |
| |
| config PREEMPT_VOLUNTARY |
| bool "Voluntary Kernel Preemption (Desktop)" |
| help |
| This option reduces the latency of the kernel by adding more |
| "explicit preemption points" to the kernel code. These new |
| preemption points have been selected to reduce the maximum |
| latency of rescheduling, providing faster application reactions, |
| at the cost of slightly lower throughput. |
| |
| This allows reaction to interactive events by allowing a |
| low priority process to voluntarily preempt itself even if it |
| is in kernel mode executing a system call. This allows |
| applications to run more 'smoothly' even when the system is |
| under load. |
| |
| Select this if you are building a kernel for a desktop system. |
| |
| config PREEMPT |
| bool "Preemptible Kernel (Low-Latency Desktop)" |
| help |
| This option reduces the latency of the kernel by making |
| all kernel code (that is not executing in a critical section) |
| preemptible. This allows reaction to interactive events by |
| permitting a low priority process to be preempted involuntarily |
| even if it is in kernel mode executing a system call and would |
| otherwise not be about to reach a natural preemption point. |
| This allows applications to run more 'smoothly' even when the |
| system is under load, at the cost of slightly lower throughput |
| and a slight runtime overhead to kernel code. |
| |
| Select this if you are building a kernel for a desktop or |
| embedded system with latency requirements in the milliseconds |
| range. |
| |
| endchoice |
| |
