Linux调度器免锁优化方法研究  

Research on Decreasing Lock Contention for Linux Scheduler

作　　者：张旭[1,2,3] 顾乃杰[1,2,3] 苏俊杰[1,2,3] 

机构地区：[1]中国科学技术大学计算机科学技术学院,合肥230027 [2]中国科学技术大学中科院沈阳计算技术研究所网络与通信联合实验室,合肥230027 [3]中国科学技术大学先进技术研究院,合肥230027

出　　处：《小型微型计算机系统》2017年第4期690-695,共6页Journal of Chinese Computer Systems

基　　金：安徽大学青年科研基金项目(KJQN1118)资助

摘　　要：Linux操作系统被广泛用于各领域,多核环境下Linux调度器依靠自旋锁保证其正确运行,这给调度器带来了严重的锁竞争.在分析Linux调度器的基础上,对其提出三个层次的免锁优化方法:基础优化、调度行为优化和基于上层应用特征的参数调优.基础优化尝试从代码层面直观地缩小程序的锁冲突域;调度行为优化针对进程创建过程中的唤醒操作提出了一种新进程延迟唤醒方法,有效地减少了进程创建过程中的锁竞争;基于上层应用特征的参数调优可以在对内核修改很小的情况下完成调度器性能提升.Linux operating system is widely used in different areas. Linux scheduler employs spinlocks to guarantee its correctness on multicore processors,but spinlocks lead to severe lock contention. This paper analyses the characteristics of spinlock operations in Linux scheduler and proposes three different optimization strategies on three different levels to decrease lock contention. The first strat- egy is to shrink the critical sections from code level;the second strategy changes the behavior of scheduler, and introduces a new meth- od, which delays the wakeup of new processes and considerably decreases the lock contention during process creation; the third strategy is tuning the key parameters of Linux scheduler according to the process features of top-level applications and it achieves reasonable performance promotion with minor modifications to the kernel.

关 键 词：LINUX内核 调度器 自旋锁 锁竞争 

分 类 号：TP311[自动化与计算机技术—计算机软件与理论]