What is difference between top and ps command?
top is mostly used interactively (try reading man page or pressing “h” while top is running) and ps is designed for non-interactive use (scripts, extracting some information with shell pipelines etc.) top allows you display of process statistics continuously until stopped vs. ps which gives you a single snapshot.
What is PR in top?
Difference Between PR or PRI and NI From the top and htop outputs above, you’ll notice that there is a column called PR and PRI receptively which shows the priority of a process. This, therefore, means that: PR or PRI – is the process’s actual priority, as seen by the Linux kernel.
Which nice value has the best scheduling?
PR — Priority The scheduling priority of the task. If you see ‘rt’ in this field, it means the task is running under ‘real time’ scheduling priority. NI is nice value of task.
Why do we use PR command?
The pr command writes the specified file or files to standard output. If you specify the – (minus sign) parameter instead of the File parameter, or if you specify neither, the pr command reads standard input. A heading that contains the page number, date, time, and name of the file separates the output into pages.
What nice values may be assigned to a process?
The nice value of a process can have a range between -20 (highest priority) to +19 (lowest priority); by default, its value is 0. If the nice value of a process is lower, it gets a higher priority, which means the CPU will execute that process more often.
What is S in top command?
‘S’ and ‘D’ are two sleep states, where the process is waiting for something to happen. The difference is that ‘S’ can be interrupted by a signal, while ‘D’ cannot (it is usually seen when the process is waiting for the disk). ‘T’ is a state where the process is stopped, usually via SIGSTOP or SIGTSTP .
How do you read Htop?
Understanding CPU Usage in htop
- Blue: Display percentage of CPU used by low priority processes. (
- Green: Displays percentage of CPU used for processes owned by normal users.
- Red: Displays percentage of CPU used by system processes.
- Orange: Displays percentage of CPU used by IRQ time.