taskset设置CPU亲和

在grup启动时传给内核参数: isolcpus=2-15, 这里表示隔离第3到16个CPU, Linux程序只跑在第一和第二个CPU上, 空闲的CPU我们可以指定跑进程了.
这是内核文档里对内核参数的解释:

isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
                        Format:
                        <cpu number>,...,<cpu number>
                        or
                        <cpu number>-<cpu number>
                        (must be a positive range in ascending order)
                        or a mixture
                        <cpu number>,...,<cpu number>-<cpu number>

                        This option can be used to specify one or more CPUs
                        to isolate from the general SMP balancing and scheduling
                        algorithms. You can move a process onto or off an
                        "isolated" CPU via the CPU affinity syscalls or cpuset.
                        <cpu number> begins at 0 and the maximum value is
                        "number of CPUs in system - 1".

                        This option is the preferred way to isolate CPUs. The
                        alternative -- manually setting the CPU mask of all
                        tasks in the system -- can cause problems and
                        suboptimal load balancer performance.

然后我们利用taskset程序来设置运行的程序跑在哪个CPU上, 本例是16个CPU, 用mask表示:

Anshion> ./test.sh &
[1] 684
Anshion> taskset -p 0x8000 684
pid 684's current affinity mask: 3
pid 684's new affinity mask: 8000

这样在top中就可以看到, 这个进程跑在15号CPU上了, top命令运行按f, 再按j, 可以显示命令运行的cpu.然后用W保存配置.

taskset -c 15 ./test.sh &

这样可以直接调用程序时指定跑在哪个CPU上.