[Kernel-packages] [Bug 1587265] Re: ubuntu not work with tickless kernel boot option
Would be nice to at least get a tickless kernel option without having to compile my own every time it's updated, it's becoming a source of frustration. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1587265 Title: ubuntu not work with tickless kernel boot option Status in linux package in Ubuntu: Confirmed Bug description: For redhat, we have such guide like https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/pdf/Performance_Tuning_Guide/Red_Hat_Enterprise_Linux-7-Performance_Tuning_Guide-en-US.pdf and for tickless kernel, (use dynamic tickless ways) 1. config grub with following cmdline $ cat /etc/default/grub # If you change this file, run 'update-grub' afterwards to update # /boot/grub/grub.cfg. # For full documentation of the options in this file, see: # info -f grub -n 'Simple configuration' GRUB_DEFAULT=0 GRUB_HIDDEN_TIMEOUT=0 GRUB_HIDDEN_TIMEOUT_QUIET=true GRUB_TIMEOUT=10 GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian` GRUB_CMDLINE_LINUX_DEFAULT="quiet splash isolcpus=1-2 nohz_full=1-2" GRUB_CMDLINE_LINUX="" I used nohz_full here, and it is CPU 1, 2 here. 2. update-grub after that. 3. Then reboot system 4. execute following $ sudo perf stat -C 1 -e irq_vectors:local_timer_entry taskset -c 1 stress -t 1 -c 1 stress: info: [3869] dispatching hogs: 1 cpu, 0 io, 0 vm, 0 hdd stress: info: [3869] successful run completed in 1s Performance counter stats for 'CPU(s) 1': 252 irq_vectors:local_timer_entry 1.001491203 seconds time elapsed It always 252, (the default 250 HZ), seems tickless kernel option not have any effect, whether config it or not, both have same results. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1587265/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
[Kernel-packages] [Bug 1587265] Re: ubuntu not work with tickless kernel boot option
This is still the case in Ubuntu 20.04: $ cat /boot/config-5.11.0-27-generic | grep HZ_FULL # CONFIG_NO_HZ_FULL is not set This is problematic insofar as HZ_FULL is apparently useful for reliable benchmarking (e.g. see https://vstinner.github.io/journey-to-stable- benchmark-system.html). Would be nice to get this fixed! -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1587265 Title: ubuntu not work with tickless kernel boot option Status in linux package in Ubuntu: Confirmed Bug description: For redhat, we have such guide like https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/pdf/Performance_Tuning_Guide/Red_Hat_Enterprise_Linux-7-Performance_Tuning_Guide-en-US.pdf and for tickless kernel, (use dynamic tickless ways) 1. config grub with following cmdline $ cat /etc/default/grub # If you change this file, run 'update-grub' afterwards to update # /boot/grub/grub.cfg. # For full documentation of the options in this file, see: # info -f grub -n 'Simple configuration' GRUB_DEFAULT=0 GRUB_HIDDEN_TIMEOUT=0 GRUB_HIDDEN_TIMEOUT_QUIET=true GRUB_TIMEOUT=10 GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian` GRUB_CMDLINE_LINUX_DEFAULT="quiet splash isolcpus=1-2 nohz_full=1-2" GRUB_CMDLINE_LINUX="" I used nohz_full here, and it is CPU 1, 2 here. 2. update-grub after that. 3. Then reboot system 4. execute following $ sudo perf stat -C 1 -e irq_vectors:local_timer_entry taskset -c 1 stress -t 1 -c 1 stress: info: [3869] dispatching hogs: 1 cpu, 0 io, 0 vm, 0 hdd stress: info: [3869] successful run completed in 1s Performance counter stats for 'CPU(s) 1': 252 irq_vectors:local_timer_entry 1.001491203 seconds time elapsed It always 252, (the default 250 HZ), seems tickless kernel option not have any effect, whether config it or not, both have same results. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1587265/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
[Kernel-packages] [Bug 1587265] Re: ubuntu not work with tickless kernel boot option
What specific kernel version had the problem? You can check with: uname -a The CONFIG_NO_HZ_FULL kernel param was turned off at some point between trusty's 3.13 and xenial's 4.4, and without that kernel param enabled the nohz_full boot param has no effect. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1587265 Title: ubuntu not work with tickless kernel boot option Status in linux package in Ubuntu: Confirmed Bug description: For redhat, we have such guide like https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/pdf/Performance_Tuning_Guide/Red_Hat_Enterprise_Linux-7-Performance_Tuning_Guide-en-US.pdf and for tickless kernel, (use dynamic tickless ways) 1. config grub with following cmdline $ cat /etc/default/grub # If you change this file, run 'update-grub' afterwards to update # /boot/grub/grub.cfg. # For full documentation of the options in this file, see: # info -f grub -n 'Simple configuration' GRUB_DEFAULT=0 GRUB_HIDDEN_TIMEOUT=0 GRUB_HIDDEN_TIMEOUT_QUIET=true GRUB_TIMEOUT=10 GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian` GRUB_CMDLINE_LINUX_DEFAULT="quiet splash isolcpus=1-2 nohz_full=1-2" GRUB_CMDLINE_LINUX="" I used nohz_full here, and it is CPU 1, 2 here. 2. update-grub after that. 3. Then reboot system 4. execute following $ sudo perf stat -C 1 -e irq_vectors:local_timer_entry taskset -c 1 stress -t 1 -c 1 stress: info: [3869] dispatching hogs: 1 cpu, 0 io, 0 vm, 0 hdd stress: info: [3869] successful run completed in 1s Performance counter stats for 'CPU(s) 1': 252 irq_vectors:local_timer_entry 1.001491203 seconds time elapsed It always 252, (the default 250 HZ), seems tickless kernel option not have any effect, whether config it or not, both have same results. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1587265/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
[Kernel-packages] [Bug 1587265] Re: ubuntu not work with tickless kernel boot option
I used the default ubuntu desktop install (amd64 14.04) version ** Changed in: linux (Ubuntu) Status: Incomplete => Confirmed -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1587265 Title: ubuntu not work with tickless kernel boot option Status in linux package in Ubuntu: Confirmed Bug description: For redhat, we have such guide like https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/pdf/Performance_Tuning_Guide/Red_Hat_Enterprise_Linux-7-Performance_Tuning_Guide-en-US.pdf and for tickless kernel, (use dynamic tickless ways) 1. config grub with following cmdline $ cat /etc/default/grub # If you change this file, run 'update-grub' afterwards to update # /boot/grub/grub.cfg. # For full documentation of the options in this file, see: # info -f grub -n 'Simple configuration' GRUB_DEFAULT=0 GRUB_HIDDEN_TIMEOUT=0 GRUB_HIDDEN_TIMEOUT_QUIET=true GRUB_TIMEOUT=10 GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian` GRUB_CMDLINE_LINUX_DEFAULT="quiet splash isolcpus=1-2 nohz_full=1-2" GRUB_CMDLINE_LINUX="" I used nohz_full here, and it is CPU 1, 2 here. 2. update-grub after that. 3. Then reboot system 4. execute following $ sudo perf stat -C 1 -e irq_vectors:local_timer_entry taskset -c 1 stress -t 1 -c 1 stress: info: [3869] dispatching hogs: 1 cpu, 0 io, 0 vm, 0 hdd stress: info: [3869] successful run completed in 1s Performance counter stats for 'CPU(s) 1': 252 irq_vectors:local_timer_entry 1.001491203 seconds time elapsed It always 252, (the default 250 HZ), seems tickless kernel option not have any effect, whether config it or not, both have same results. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1587265/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
[Kernel-packages] [Bug 1587265] Re: ubuntu not work with tickless kernel boot option
Did this issue start happening after an update/upgrade? Was there a kernel version where you were not having this particular problem? This will help determine if the problem you are seeing is the result of a regression, and when this regression was introduced. If this is a regression, we can perform a kernel bisect to identify the commit that introduced the problem. ** Changed in: linux (Ubuntu) Importance: Undecided => Medium ** Changed in: linux (Ubuntu) Status: Confirmed => Incomplete ** Tags added: kernel-da-key -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1587265 Title: ubuntu not work with tickless kernel boot option Status in linux package in Ubuntu: Incomplete Bug description: For redhat, we have such guide like https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/pdf/Performance_Tuning_Guide/Red_Hat_Enterprise_Linux-7-Performance_Tuning_Guide-en-US.pdf and for tickless kernel, (use dynamic tickless ways) 1. config grub with following cmdline $ cat /etc/default/grub # If you change this file, run 'update-grub' afterwards to update # /boot/grub/grub.cfg. # For full documentation of the options in this file, see: # info -f grub -n 'Simple configuration' GRUB_DEFAULT=0 GRUB_HIDDEN_TIMEOUT=0 GRUB_HIDDEN_TIMEOUT_QUIET=true GRUB_TIMEOUT=10 GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian` GRUB_CMDLINE_LINUX_DEFAULT="quiet splash isolcpus=1-2 nohz_full=1-2" GRUB_CMDLINE_LINUX="" I used nohz_full here, and it is CPU 1, 2 here. 2. update-grub after that. 3. Then reboot system 4. execute following $ sudo perf stat -C 1 -e irq_vectors:local_timer_entry taskset -c 1 stress -t 1 -c 1 stress: info: [3869] dispatching hogs: 1 cpu, 0 io, 0 vm, 0 hdd stress: info: [3869] successful run completed in 1s Performance counter stats for 'CPU(s) 1': 252 irq_vectors:local_timer_entry 1.001491203 seconds time elapsed It always 252, (the default 250 HZ), seems tickless kernel option not have any effect, whether config it or not, both have same results. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1587265/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
[Kernel-packages] [Bug 1587265] Re: ubuntu not work with tickless kernel boot option
I could not run it, as test@test-ThinkCentre-M92P:~$ apport-collect 1587265 ERROR: connecting to Launchpad failed: [Errno 110] Connection timed out You can reset the credentials by removing the file "/home/test/.cache/apport/launchpad.credentials" and also I am not sure if that report could collect sensitive info from my system or not, so I could not upload such log now. I think the description is clear, so mark it confirmed now, Let me know if have other ways to collect logs. Thanks ** Changed in: linux (Ubuntu) Status: Incomplete => Confirmed -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1587265 Title: ubuntu not work with tickless kernel boot option Status in linux package in Ubuntu: Confirmed Bug description: For redhat, we have such guide like https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/pdf/Performance_Tuning_Guide/Red_Hat_Enterprise_Linux-7-Performance_Tuning_Guide-en-US.pdf and for tickless kernel, (use dynamic tickless ways) 1. config grub with following cmdline $ cat /etc/default/grub # If you change this file, run 'update-grub' afterwards to update # /boot/grub/grub.cfg. # For full documentation of the options in this file, see: # info -f grub -n 'Simple configuration' GRUB_DEFAULT=0 GRUB_HIDDEN_TIMEOUT=0 GRUB_HIDDEN_TIMEOUT_QUIET=true GRUB_TIMEOUT=10 GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian` GRUB_CMDLINE_LINUX_DEFAULT="quiet splash isolcpus=1-2 nohz_full=1-2" GRUB_CMDLINE_LINUX="" I used nohz_full here, and it is CPU 1, 2 here. 2. update-grub after that. 3. Then reboot system 4. execute following $ sudo perf stat -C 1 -e irq_vectors:local_timer_entry taskset -c 1 stress -t 1 -c 1 stress: info: [3869] dispatching hogs: 1 cpu, 0 io, 0 vm, 0 hdd stress: info: [3869] successful run completed in 1s Performance counter stats for 'CPU(s) 1': 252 irq_vectors:local_timer_entry 1.001491203 seconds time elapsed It always 252, (the default 250 HZ), seems tickless kernel option not have any effect, whether config it or not, both have same results. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1587265/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
