Limit the output of the TOP command to a specific process name

If you call the top command, you get all the running processes. But how can I limit the output only to a certain process name like "java"?

I've tried this top -l 2 | grep java but in this way you get only snapshots and not a continuously updated list. And top -l 0 | grep java is not really clear.

I prefer the following so I can still use top interactively without having to look up the pids each time I run it:

top -p `pgrep process-name | tr "\\n" "," | sed 's/,$//'`

Of course if the processes change you'll have to re-run the command.

Explanation:

• pgrep process-name returns a list of process ids which are separated by newlines
• tr "\\n" "," translates these newlines into commas, because top wants a comma-separated list of process ids
• sed is a stream editor, and sed 's/,$//' is used here to remove the trailing comma

Find the pids of the processes you want to monitor and then use the -p option which allows you to provide a list of pids to the top command.

Example:

top -p 18884 -p 18892 -p 18919

  PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME CPU COMMAND
18884 user  25   0  672M  95M  9476 S     0.0  1.1   0:02   1 java
18892 user  25   0 2280M 123M 12252 S     0.0  1.5   0:05   1 java
18919 user  22   0 1492M 198M 28708 S     0.0  2.4   0:07   1 java

(I believe you can also pass in a comma-separated list.)