Exporting top data to a file

user_18371696 0
Viewed 66

So I've been trying to run the following command to check the consumption by the firefox process.

top -b | grep "firefox"

Now I can see the desired output in terminal for it. But now when I try to export it to a file, I'm not able to. The command I'm running is:

top -b | grep "firefox" >> filename or top -b | grep "firefox" > filename

Please help.

centos monitoring linux
2 Answers

You need the -n parm for top. For example,

top -b -n 1 | grep "firefox" >> firefox.out

Without -n 1 top will keep processing and will never make it to grep.. From the man page for top:

   -n  :Number-of-iterations limit as:  -n number
        Specifies  the  maximum  number of iterations, or frames, top
        should produce before ending.

Updated code with a while loop. It will loop forever unless you use something like cntr variable. Remove the cntr code if you want continuous monitoring:

#!/bin/sh
#
not_done=1
cntr=0
# Look for process firefox every 1 seconds
while [ "$not_done" -eq 1 ]
do
  top -b -n 1 | grep "firefox" >> /tmp/firefox.out
  sleep 1
  ((cntr=cntr+1))
  # Addition logic to break out of loop after 10 iterations
  if [ "$cntr" -eq 10 ]
  then
    not_done=0
  fi
  echo "cntr=$cntr"
done
user_1587870

You have to add in the command the flag -n Change the number of processes to show. You will be prompted to enter the number.

To take a snapshot of a specific process in top utility, execute command with the PID (-p) flag.

Also i recommed if you want to take snapshots for the process one (PID), and get taking three snapshots of the PID: top -p 678 -b -n3 > monitoring.out

user_192488120
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