How to change /proc/sys/kernel/perf_event_paranoid permanently

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#1

I have the newest Tumbleweed system. How can I change /proc/sys/kernel/perf_event_paranoid from 2 to 0?
I learned that it doesn’t work with vi and with echo 2 > … it won’t be permanent. As I also found some warnings about this
I want to ask before I do anything I don’t really understand.

The reason is that I want to use intel’s vTune.

Thanks!

#2

As the /proc file system does not really exist, but is a way to have an interface to kernel parameters/structures, it only exists as long as the kernel runs. Thus it is gone at shutdown. So not permanent changes there.

As perf_event_paranoid is a kernel parameter, there are several options to change it:

  • generate your kernel with the parameter set to your wish, not something that you will prefer imho;
  • add it to the line with the kernel parameters in the GRUB2 configuration using YaST > System > Bootloader;
  • add the line
echo 2 >/proc/sys/kernel/perf_event_paranoid

to /etc/init.d/boot.local.

BTW, I have no idea what the result of that setting is, this is only a technical description on how to do it, not if it is save or beneficial.

BTW in my openSUSE 13.1 system it is set to 1., not to 0 as you say it is in your Tumbleweed.

#3

Thanks for the info. BTW default was 2 in my TW.