Several things that should be done after ubuntu installation

1. set the swap space usage. open the terminal and run: cat/proc/sys/vm/swappiness. the displayed value is 60. then run: sudogedit/etc/sysctl. conf, where gedit is the default ubuntu text editor. if vim is installed, replace it with vim ,... 1. set the swap space usage. open the terminal and run: cat/proc/sys/vm/swappiness. the displayed value is 60. then run: sudo gedit/etc/sysctl. conf, where gedit is the default ubuntu text editor. if vim is installed, replace it with vim. add the following content at the end of the opened text: vm. swappiness = 5 (or 10). 5 ~ recommended ~ 10), save and exit. Then restart the system and run cat/proc/sys/vm/swappiness on the terminal. the displayed value must be a set value. 2. after ubuntu is installed, the default software source is a Chinese server. we can change it to a specific server site to get a fast download speed, after changing the site to a specific server site such as Beijing Institute of Technology, Shanghai Jiao Tong University, and HKUST in the software source settings, run sudo apt-get update on the terminal to update the software source cache, then run sudo apt-get upgrade to update the system. 3. install common plug-in Decoders