直接参考oracle官方建议吧：
建议在linux环境下设置1~10之间即可，默认的60太大了。
vm.swappiness=1
vm.swappiness - 0 or 1? (Doc ID 1917687.1)
Should I use 0 or 1 for vm.swappiness?
SOLUTION
These instructions are valid for Red Hat Enterprise Linux and Oracle Linux systems, but should be similar for other Linux distros.
There is some confusion about using a value of 0 or 1 for the vm.swappiness kernel parameter.
The confusion about vm.swappiness comes from the fact that in older Red Hat kernels, a value of 0 for vm.swappiness resulted in the minimal amount of swapping to avoid an out of memory condition. In newer kernels (as of RHEL kernel 2.6.32-303), a value of 0 will completely disable swap, but a value of 1 will provide the minimal amount of swapping to avoid an out of memory condition.
My general recommendation is to set vm.swappiness to a value of 1 for a dedicated MySQL server. There is not much practical difference between a value of 0 and a value of 1 on older kernels, but 1 is the safe setting to avoid an OOM condition on newer kernels (assuming that some swap space is available, of course).
To set vm.swappiness to 1 and make it persistent across reboots:
echo "vm.swappiness=1" >> /etc/sysctl.conf
sysctl -p
