Software & Apps Linux Determine System Stability Using the uptime Command The 'uptime' and 'w' commands show basic system info including uptimes By Gary Newell Writer Gary Newell was a freelance contributor, application developer, and software tester with 20+ years in IT, working on Linux, UNIX, and Windows. our editorial process Gary Newell Updated January 22, 2020 Linux Switching from Windows Tweet Share Email Verify the amount of time your Linux-based computer has run between reboots or powerdown events using the uptime command. How Long Has Your System Been Running? The simplest way to find out how long your system has been running is to enter the uptime command. The default output displays: The current time.How long the system has been running.The number of users that are logged in.The load average for the past 1, 5 and 15 minutes. The load averages show the average number of processes that are in a runnable or uninterruptable state. Modify the command by using the -s and -p switches. The command uptime -s shows the start time of the machine. The command uptime -p offers an easy-to-comprehend description of total uptime, in plain English. Alternate Way to Show Your System Uptime The uptime command isn't the only way to show the system uptime. You can achieve the same thing with the simple w command. The output from the w command is as follows: userttyfromlogin timeidle timeJCPUPCPUWHAT The w command shows more than just the current uptime. It shows who is logged in and what they are currently doing. The JCPU is the time used by all processes attached to the terminal and the PCPU shows the time used by the current process in the WHAT column.