0003 prompt "Preemption Model"
0004 default PREEMPT_NONE
0006 config PREEMPT_NONE
0007 bool "No Forced Preemption (Server)"
0009 This is the traditional Linux preemption model, geared towards
0010 throughput. It will still provide good latencies most of the
0011 time, but there are no guarantees and occasional longer delays
0012 are possible.
0014 Select this option if you are building a kernel for a server or
0015 scientific/computation system, or if you want to maximize the
0016 raw processing power of the kernel, irrespective of scheduling
0019 config PREEMPT_VOLUNTARY
0020 bool "Voluntary Kernel Preemption (Desktop)"
0022 This option reduces the latency of the kernel by adding more
0023 "explicit preemption points" to the kernel code. These new
0024 preemption points have been selected to reduce the maximum
0025 latency of rescheduling, providing faster application reactions,
0026 at the cost of slightly lower throughput.
0028 This allows reaction to interactive events by allowing a
0029 low priority process to voluntarily preempt itself even if it
0030 is in kernel mode executing a system call. This allows
0031 applications to run more 'smoothly' even when the system is
0032 under load.
0034 Select this if you are building a kernel for a desktop system.
0036 config PREEMPT
0037 bool "Preemptible Kernel (Low-Latency Desktop)"
0038 select PREEMPT_COUNT
0039 select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK
0041 This option reduces the latency of the kernel by making
0042 all kernel code (that is not executing in a critical section)
0043 preemptible. This allows reaction to interactive events by
0044 permitting a low priority process to be preempted involuntarily
0045 even if it is in kernel mode executing a system call and would
0046 otherwise not be about to reach a natural preemption point.
0047 This allows applications to run more 'smoothly' even when the
0048 system is under load, at the cost of slightly lower throughput
0049 and a slight runtime overhead to kernel code.
0051 Select this if you are building a kernel for a desktop or
0052 embedded system with latency requirements in the milliseconds
0057 config PREEMPT_COUNT