Quick Tip: Get on ‘top’ of VPS Processes
Whether you’ve just noticed some sluggishness on your VPS or you’ve run into a situation where you’re using more than your fair share of your shared resources, there might come a time when you need to figure out which processes are taking up the most CPU/RAM.
Linux installations come with a bevy of tools that are acceptable for this purpose, but none are quite as universal as
top. Or, for those who like a little more interactivity,
top displays the most CPU intensive processes currently running on your VPS. It will update the list every 3 seconds so that you can understand if a process is spiking CPU usage every so often or is a consistent hog.
You can use a number of different options while running
top to customize its output.
Specify the refresh period, in seconds. The below command will change the period to 10 seconds.
top -d 10
Sort by specific column. First, type
top -O to see which columns are available to you, then use
top -o to specify. For example, you can search by
TIME to see which processes have been running longest.
top -o TIME
Or based on CPU usage.
top -o %CPU
Show processes from a specific user. Could be useful for those with more complex deployments.
top -u joel
Show only certain process IDs.
top -p 12345
top is running, there’s a lot you can do to customize or drill down into the output.
|d||Change the refresh rate.|
|z||Turn on/off colors.|
|l||Hide/display the load average (top row).|
|t||Changes how the tasks are displayed.|
|m||Changes how memory usage is displayed.|
|1||Switch between one/many CPU mode.|
|R||Reverse the sorting order.|
|c||Display the absolute path of the process.|
|k||Kill the process by its PID.|
|P||Sort processes by CPU utilization, high to low.|
|M||Sort processes by RAM utilization, high to low.|
|n||Limit the number of processes shown.|
Finally, you can add new fields to the top output. Press
top is running, which will display all your options. Use the arrow keys to navigate around, and then hit
d to enable/disable a given field. Enabled fields will have an asterisk next to them, and will be bolded.
By combining these techniques together, you can instantly get a handle on your most taxing processes. And then you can start using
htop to dive even deeper.