Linux Top Command

Top command belongs to PROCPS, project address http://procps.sourceforge.net

From a tall man's blog to see, he summed up a bit to do a memo

Common Interactive Commands

Execute Top command

Z: Turn color display on/off
X: Highlight Row sequence

1: Show the running status of each CPU

<    : Changing the row sequence >    

W    : Put the current profile into the home directory. TOPRC in the configuration file F or O: Support for a stronger selection of the sequence of rows common command-line arguments

  -B: Batch operation mode, use this parameter to use the top command in the script
   -N: Use with-B to indicate a certain number of times after re-flushing exit-D   : Refresh delay time. For example,-D 5 means top refreshes every 5 seconds. (default is 3 seconds)

Monitor is processes with an effective UID or the user name matching that given. (Valid users only)
-u:monitor by user as:-U Somebody
Monitor only processes with a UID or the user name matching that given. This matches real, effective, saved, and filesystem UIDs. (Show actual or active users)

 
   
  

  
    
   
The simplest difference is to change the password with the normal user executing the passwd command.
  
    
   
Top–u username,
  
    
   
The passwd process is not visible because-u can only view valid users, the passwd process defaults to suid, and the active user is root
  
    
   
Top–u username,
  
    
   
You can see the passwd process, and the process shows the user as root instead of username
 
   
  

Linux Top Command