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Description of problem: When a realtime system is updated with the tuned packages: tuned-profiles-nfv-2.5.1-4.el7_2.4.noarch tuned-profiles-realtime-2.5.1-4.el7_2.4.noarch tuned-2.5.1-4.el7_2.4.noarch The settings in /usr/lib/tuned/realtime-virtual-guest/tuned.conf are over-written. Version-Release number of selected component (if applicable): How reproducible: 100% Steps to Reproduce: 1.Install tuned-profiles-nfv-2.5.1-4.el7_2.3.noarch,tuned-profiles-realtime-2.5.1-4.el7_2.3.noarch,tuned-2.5.1-4.el7_2.3.noarch packages. 2.Edit /usr/lib/tuned/realtime-virtual-guest/tuned.conf so that the bootloader section reads as follows: [bootloader] cmdline=isolcpus=${isolated_cores} intel_pstate=disable nosoftlockup 3.reboot 4) Install the newer version of tuned: tuned-profiles-nfv-2.5.1-4.el7_2.4.noarch tuned-profiles-realtime-2.5.1-4.el7_2.4.noarch tuned-2.5.1-4.el7_2.4.noarch 5) reboot Actual results: "nohz=on nohz_full=${isolated_cpus}" appear in the kernel command line and in /usr/lib/tuned/realtime-virtual-guest/tuned.conf in the bootloader section. Expected results: The /usr/lib/tuned/realtime-virtual-guest/tuned.conf should have the settings made in Step 2. The kernel command line should not have nohz set. Additional info:
I was wrong to ask you to open this BZ. Replacing tuned.conf is the correct behavior: it's where tuned stores all its tunings. The file that should not be replaced is /etc/tuned/realtime-virtual-host-variables.conf. We edit tuned.conf to disable nohz in the guest when running cyclcitest. This is because cyclictest is able to trig some worse case scenarios in nohz (which polling apps like DPDK won't trig). We should open a BZ for this issue instead.
Yes, you shouldn't edit system profiles in /usr/lib/tuned. If you need to customize them beyond /etc/tuned/realtime-virtual-host-variables.conf possibilities, you can: a) copy the profile to /etc/tuned and customize it there, i.e.: # cp /usr/lib/tuned/realtime-virtual-guest /etc/tuned In case there profiles with the same name in /etc/tuned and /usr/lib/tuned, the /etc/tuned takes precedence. pros: you can easily customize the profile cons: if system profile is updated, your profile in /etc/tuned will not be updated, you will need to merge the changes by hand b) create new profile /etc/tuned and include the system profile, then override only what you need, e.g: # mkdir -p /etc/tuned/realtime-virtual-guest-custom # cat << :EOF > /etc/tuned/realtime-virtual-guest-custom/tuned.conf [main] include=realtime-virtual-guest YOUR_OVERRIDES_HERE :EOF # tuned-adm profile realtime-virtual-guest-custom pros: easy to maintain and updates of system profiles will be reflected in your custom profile cons: overrides could be sometime less clear than full text edits
Option b seems better, but I have to give it a try to be sure. Thanks for the feedback.