CentOS - Feb 2014 - OT: Howto to capture taskset output command

Hi all,

 I am trying to set processor affinity for a specific process using a
shell script without result. Script:

#!/bin/sh -x

cpu_affinity_ok="2"
cpu_affinity="taskset -p -c `cat /tmp/test.pid` | awk '{print
$6}'"

if [ -f /tmp/test.pid ]; then
    if [ "$cpu_affinity" == "$cpu_affinity_ok" ]; then
       exit 0
     else
        taskset -p -c 2 `cat /tmp/test.pid`
     fi
fi

This script doesn't works:

[root at cos01 bin]# taskset -p -c 27756
pid 27756's current affinity list: 2

Excecuting script:

[root at cos01 bin]# ./my_cpu_affinitty
+ cpu_affinity_ok=2
++ cat /tmp/test.pid
+ cpu_affinity='taskset -p -c 27756 | awk '\''{print
}'\'''
+ '[' -f /tmp/test.pid ']'
+ '[' 'taskset -p -c 27756 | awk '\''{print
}'\''' == 2 ']'
++ cat /tmp/test.pid
+ taskset -p -c 2 27756
pid 27756's current affinity list: 2
pid 27756's new affinity list: 2

 As you can see, function compare under "if" statement doesn't
works ...

Any idea??

Thanks.

On Wed, Feb 26, 2014 at 6:57 AM, C. L. Martinez <carlopmart at
gmail.com>wrote:
>     if [ "$cpu_affinity" == "$cpu_affinity_ok" ]; then
>
are you comparing strings or integers?
# man test
       STRING1 = STRING2
              the strings are equal
       INTEGER1 -eq INTEGER2
              INTEGER1 is equal to INTEGER2

From: C. L. Martinez <carlopmart at gmail.com>
> I am trying to set processor affinity for a specific process using a
> shell script without result. Script:
> 
> #!/bin/sh -x
> 
> cpu_affinity_ok="2"
> cpu_affinity="taskset -p -c `cat /tmp/test.pid` | awk '{print 
> $6}'"
> 
> if [ -f /tmp/test.pid ]; then
> ? ? if [ "$cpu_affinity" == "$cpu_affinity_ok" ]; then
> ? ? ?  exit 0
> ? ?  else
> ? ? ? ? taskset -p -c 2 `cat /tmp/test.pid`
> ? ?  fi
> fi
> 
> This script doesn't works:
> 
> As you can see, function compare under "if" statement doesn't
> works ...
This works for me:

function cpu_affinity() {
? taskset -p -c $1 | awk ' { print $6 } '
}

and

PID=`cat /tmp/test.pid`
if [ $(cpu_affinity $PID) -eq $cpu_affinity_ok ]; then

JD