mjhjmtu

I want to make a shell script that finds all active processes and to print to the user the scheduling policy.I want the result to be like this.

pid 3042's current scheduling policy: SCHED_OTHER
pid 3042's current scheduling priority: 0
pid 3043's current scheduling policy: SCHED_OTHER
pid 3043's current scheduling priority: 0
pid 3044's current scheduling policy: SCHED_OTHER
pid 3044's current scheduling priority: 0

I have managed to do this but only for a single process with the use of ps and chrt commands.

I've come up with the following command using ps and awk which gives very similar output with only a small difference in that it shows abbreviated names of the scheduling class. The following mapping could help you :

• 
  TS is SCHED_OTHER
  


• 
  RR is SCHED_RR
  


• 
  FF is SCHED_FIFO
  

The command:

ps -e -o s,pid,cls,pri | grep ^R | awk -v sq="'" 'print "pid",$2,sq,"s current scheduling policy:",$3,"npid",$2,sq,"s current priority:",$4'

Running the above command on my host gives the following output:

pid 8456 ' s current scheduling policy: TS 
pid 8456 ' s current priority: 19
pid 12552 ' s current scheduling policy: TS 
pid 12552 ' s current priority: 19

EDIT

Based on the comment, the following command gives an exact output using chrt and assuming that an active process is a running or a runnable process R:

ps -e -o s,pid | grep ^R | awk 'system("chrt -p " $2)'

In case you want to get the output for all the processes (Running, Sleeping, Stopped & Zombie), you would like to use the following command:

ls /proc | grep -e ^[0-9] | awk 'system("chrt -p " $0)'|more

I found two ways for doing it they may not be optimal but they get the job done.

1. #! /bin/bash
ps -u |grep [0-9]|awk 'print $2' > test.txt
cat test.txt |while read line
do
chrt -p $line 2 > /dev/null
done


2.

With this way you don't create unnecessary file.

ps -u|grep [0-9]|awk 'system("chrt -p" $2) 2 > /dev/null