从sof开始，深入理解Linux虚拟文件系统

-bash-4.2$ df -ThFilesystem     Type      Size  Used Avail Use% Mounted on/dev/vda1      ext4       30G    30G 0         100% /devtmpfs       devtmpfs  489M     0  489M   0% /devtmpfs          tmpfs     497M     0  497M   0% /dev/shmtmpfs          tmpfs     497M   50M  447M  11% /runtmpfs          tmpfs     497M     0  497M   0% /sys/fs/cgroup