linux中free命令的available值是如何计算的？

Question

[root@localhost ~]# free -h
              total        used        free      shared  buff/cache   available
Mem:           489M        124M         24M         28M        339M        314M
Swap:            0B          0B          0B

请问大神们，available项是如何计算出来的呢？在统计内存使用率时这项是否可参考？

Answer 1

cat /proc/meminfo
If you are using centos/fedora/rhel, install the package kernel-docs
arch linux, then install linux-docs
and find filesystems/proc.txt in the package File, there will be detailed explanation in it
In addition, you can also refer to man 5 proc