ubuntu 16.04 server - change screen resolution

Based on the various modifications before, the desktop that you see when you turn on the computer has become an unbearably large icon

In fact, the larger the icon is because the resolution is too small. To adjust the resolution, please refer to the following URL: http://www.360doc.com/content/17/0323/15/17572791_639467185.shtml

But when I was running, only these two sentences were running without error

xrandr

cvt 1920 1080

After the statement runs, an error will be reported, and the resolution is changed after restarting, which is also amazing.