[Group.of.nepali.translators] [Bug 1579278] Re: Consider changing default CPU frequency scaling governor back to "performance" (Ubuntu Server)
In yakkety I'll add an ondemand.service to systemd, as /etc/init.d/ondemand fell out of the standard installation (as "initscripts" is now -- thankfully -- gone). I'll keep the xenial task in case someone is interested in SRUing this. ** Changed in: sysvinit (Ubuntu) Status: New => Invalid ** Changed in: sysvinit (Ubuntu Xenial) Status: New => Triaged ** Also affects: systemd (Ubuntu) Importance: Undecided Status: New ** Changed in: systemd (Ubuntu Xenial) Status: New => Invalid ** Changed in: systemd (Ubuntu) Status: New => In Progress ** Changed in: systemd (Ubuntu Xenial) Assignee: (unassigned) => Martin Pitt (pitti) ** Changed in: systemd (Ubuntu) Importance: Undecided => Medium ** Changed in: sysvinit (Ubuntu Xenial) Importance: Undecided => Medium ** Summary changed: - Consider changing default CPU frequency scaling governor back to "performance" (Ubuntu Server) + Keep powersave CPU frequency scaling governor for CPUs that support intel_pstate -- You received this bug notification because you are a member of नेपाली भाषा समायोजकहरुको समूह, which is subscribed to Xenial. Matching subscriptions: Ubuntu 16.04 Bugs https://bugs.launchpad.net/bugs/1579278 Title: Keep powersave CPU frequency scaling governor for CPUs that support intel_pstate Status in linux package in Ubuntu: Invalid Status in systemd package in Ubuntu: In Progress Status in sysvinit package in Ubuntu: Invalid Status in linux source package in Xenial: Invalid Status in systemd source package in Xenial: Invalid Status in sysvinit source package in Xenial: Triaged Bug description: Hi, With the new Ubuntu archive servers, we saw constantly high load and after some tinkering, we found that it was mostly CPUs being woken up to see if they should enter idle states. Changing the CPU frequency scaling governor to "performance" saw a considerable drop. Perf report using the following commands: | perf record -g -a sleep 10 | perf report | Samples: 287K of event 'cycles:pp', Event count (approx.): 124776998906 | Children Self Command Shared Object Symbol | + 55.24% 0.20% swapper [kernel.kallsyms] [k] cpu_startup_entry | + 53.51% 0.00% swapper [kernel.kallsyms] [k] start_secondary | + 53.02% 0.08% swapper [kernel.kallsyms] [k] call_cpuidle | + 52.94% 0.02% swapper [kernel.kallsyms] [k] cpuidle_enter | + 31.81% 0.67% swapper [kernel.kallsyms] [k] cpuidle_enter_state | + 29.59% 0.12% swapper [kernel.kallsyms] [k] acpi_idle_enter | + 29.45% 0.05% swapper [kernel.kallsyms] [k] acpi_idle_do_entry | + 29.43%29.43% swapper [kernel.kallsyms] [k] acpi_processor_ffh_cstate_enter | + 20.51% 0.04% swapper [kernel.kallsyms] [k] ret_from_intr | + 20.47% 0.12% swapper [kernel.kallsyms] [k] do_IRQ | + 19.30% 0.07% swapper [kernel.kallsyms] [k] irq_exit | + 19.18% 0.07% apache2 [kernel.kallsyms] [k] entry_SYSCALL_64_fastpath | + 18.80% 0.17% swapper [kernel.kallsyms] [k] __do_softirq | + 16.45% 0.11% swapper [kernel.kallsyms] [k] net_rx_action | + 16.25% 0.43% swapper [kernel.kallsyms] [k] be_poll | + 14.74% 0.21% swapper [kernel.kallsyms] [k] be_process_rx | + 13.61% 0.07% swapper [kernel.kallsyms] [k] napi_gro_frags | + 12.58% 0.04% swapper [kernel.kallsyms] [k] netif_receive_skb_internal | + 12.48% 0.03% swapper [kernel.kallsyms] [k] __netif_receive_skb | + 12.42% 0.24% swapper [kernel.kallsyms] [k] __netif_receive_skb_core | + 12.41% 0.00% apache2 [unknown] [k] 0x7f27983b5028 | + 12.41% 0.00% apache2 [unknown] [k] 0x7f2798369028 | + 11.49% 0.16% swapper [kernel.kallsyms] [k] ip_rcv | + 11.29% 0.09% swapper [kernel.kallsyms] [k] ip_rcv_finish | + 10.77% 0.05% swapper [kernel.kallsyms] [k] ip_local_deliver | + 10.70% 0.06% swapper [kernel.kallsyms] [k] ip_local_deliver_finish | + 10.55% 0.22% swapper [kernel.kallsyms] [k] tcp_v4_rcv | + 10.10% 0.00% apache2 [unknown] [k] | + 10.01% 0.04% swapper [kernel.kallsyms] [k] tcp_v4_do_rcv Expanding in a few of those, you'll see: | - 55.24% 0.20% swapper [kernel.kallsyms] [k] cpu_startup_entry |- 55.04% cpu_startup_entry | - 52.98% cal
[Group.of.nepali.translators] [Bug 1579278] Re: Consider changing default CPU frequency scaling governor back to "performance" (Ubuntu Server)
Ah thanks. So maybe /etc/init.d/ondemand should have something to override or disable it (say DISABLE=1 in /etc/default/ondemand)? Looking at it currently, it seems to prefer governors in this order - interactive, ondemand, powersave. Even an option in /etc/default/ondemand to specify the preferred would be nice (e.g. PREFERRED_GOVERNOR=performance). ** Also affects: sysvinit (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of नेपाली भाषा समायोजकहरुको समूह, which is subscribed to Xenial. Matching subscriptions: Ubuntu 16.04 Bugs https://bugs.launchpad.net/bugs/1579278 Title: Consider changing default CPU frequency scaling governor back to "performance" (Ubuntu Server) Status in linux package in Ubuntu: Invalid Status in sysvinit package in Ubuntu: New Status in linux source package in Xenial: Invalid Status in sysvinit source package in Xenial: New Bug description: Hi, With the new Ubuntu archive servers, we saw constantly high load and after some tinkering, we found that it was mostly CPUs being woken up to see if they should enter idle states. Changing the CPU frequency scaling governor to "performance" saw a considerable drop. Perf report using the following commands: | perf record -g -a sleep 10 | perf report | Samples: 287K of event 'cycles:pp', Event count (approx.): 124776998906 | Children Self Command Shared Object Symbol | + 55.24% 0.20% swapper [kernel.kallsyms] [k] cpu_startup_entry | + 53.51% 0.00% swapper [kernel.kallsyms] [k] start_secondary | + 53.02% 0.08% swapper [kernel.kallsyms] [k] call_cpuidle | + 52.94% 0.02% swapper [kernel.kallsyms] [k] cpuidle_enter | + 31.81% 0.67% swapper [kernel.kallsyms] [k] cpuidle_enter_state | + 29.59% 0.12% swapper [kernel.kallsyms] [k] acpi_idle_enter | + 29.45% 0.05% swapper [kernel.kallsyms] [k] acpi_idle_do_entry | + 29.43%29.43% swapper [kernel.kallsyms] [k] acpi_processor_ffh_cstate_enter | + 20.51% 0.04% swapper [kernel.kallsyms] [k] ret_from_intr | + 20.47% 0.12% swapper [kernel.kallsyms] [k] do_IRQ | + 19.30% 0.07% swapper [kernel.kallsyms] [k] irq_exit | + 19.18% 0.07% apache2 [kernel.kallsyms] [k] entry_SYSCALL_64_fastpath | + 18.80% 0.17% swapper [kernel.kallsyms] [k] __do_softirq | + 16.45% 0.11% swapper [kernel.kallsyms] [k] net_rx_action | + 16.25% 0.43% swapper [kernel.kallsyms] [k] be_poll | + 14.74% 0.21% swapper [kernel.kallsyms] [k] be_process_rx | + 13.61% 0.07% swapper [kernel.kallsyms] [k] napi_gro_frags | + 12.58% 0.04% swapper [kernel.kallsyms] [k] netif_receive_skb_internal | + 12.48% 0.03% swapper [kernel.kallsyms] [k] __netif_receive_skb | + 12.42% 0.24% swapper [kernel.kallsyms] [k] __netif_receive_skb_core | + 12.41% 0.00% apache2 [unknown] [k] 0x7f27983b5028 | + 12.41% 0.00% apache2 [unknown] [k] 0x7f2798369028 | + 11.49% 0.16% swapper [kernel.kallsyms] [k] ip_rcv | + 11.29% 0.09% swapper [kernel.kallsyms] [k] ip_rcv_finish | + 10.77% 0.05% swapper [kernel.kallsyms] [k] ip_local_deliver | + 10.70% 0.06% swapper [kernel.kallsyms] [k] ip_local_deliver_finish | + 10.55% 0.22% swapper [kernel.kallsyms] [k] tcp_v4_rcv | + 10.10% 0.00% apache2 [unknown] [k] | + 10.01% 0.04% swapper [kernel.kallsyms] [k] tcp_v4_do_rcv Expanding in a few of those, you'll see: | - 55.24% 0.20% swapper [kernel.kallsyms] [k] cpu_startup_entry |- 55.04% cpu_startup_entry | - 52.98% call_cpuidle | + 52.93% cpuidle_enter | + 0.00% ret_from_intr |0.00% cpuidle_enter_state |0.00% irq_entries_start | + 1.14% cpuidle_select | + 0.47% schedule_preempt_disabled | 0.10% rcu_idle_enter | 0.09% rcu_idle_exit | + 0.05% ret_from_intr | + 0.05% tick_nohz_idle_enter | + 0.04% arch_cpu_idle_enter | 0.02% cpuidle_enter | 0.02% tick_check_broadcast_expired | + 0.01% cpuidle_reflect | 0.01% menu_reflect | 0.01% atomic_notifier_call_chain | 0.01% local_touch_nmi | 0.01% cpuidle_not_available | 0.
[Group.of.nepali.translators] [Bug 1579278] Re: Consider changing default CPU frequency scaling governor back to "performance" (Ubuntu Server)
The default is already CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y. However, it can be changed from user space. I suggest looking at /etc/init.d/ondemand ** Changed in: linux (Ubuntu) Status: Triaged => Invalid -- You received this bug notification because you are a member of नेपाली भाषा समायोजकहरुको समूह, which is subscribed to Xenial. Matching subscriptions: Ubuntu 16.04 Bugs https://bugs.launchpad.net/bugs/1579278 Title: Consider changing default CPU frequency scaling governor back to "performance" (Ubuntu Server) Status in linux package in Ubuntu: Invalid Status in linux source package in Xenial: Invalid Bug description: Hi, With the new Ubuntu archive servers, we saw constantly high load and after some tinkering, we found that it was mostly CPUs being woken up to see if they should enter idle states. Changing the CPU frequency scaling governor to "performance" saw a considerable drop. Perf report using the following commands: | perf record -g -a sleep 10 | perf report | Samples: 287K of event 'cycles:pp', Event count (approx.): 124776998906 | Children Self Command Shared Object Symbol | + 55.24% 0.20% swapper [kernel.kallsyms] [k] cpu_startup_entry | + 53.51% 0.00% swapper [kernel.kallsyms] [k] start_secondary | + 53.02% 0.08% swapper [kernel.kallsyms] [k] call_cpuidle | + 52.94% 0.02% swapper [kernel.kallsyms] [k] cpuidle_enter | + 31.81% 0.67% swapper [kernel.kallsyms] [k] cpuidle_enter_state | + 29.59% 0.12% swapper [kernel.kallsyms] [k] acpi_idle_enter | + 29.45% 0.05% swapper [kernel.kallsyms] [k] acpi_idle_do_entry | + 29.43%29.43% swapper [kernel.kallsyms] [k] acpi_processor_ffh_cstate_enter | + 20.51% 0.04% swapper [kernel.kallsyms] [k] ret_from_intr | + 20.47% 0.12% swapper [kernel.kallsyms] [k] do_IRQ | + 19.30% 0.07% swapper [kernel.kallsyms] [k] irq_exit | + 19.18% 0.07% apache2 [kernel.kallsyms] [k] entry_SYSCALL_64_fastpath | + 18.80% 0.17% swapper [kernel.kallsyms] [k] __do_softirq | + 16.45% 0.11% swapper [kernel.kallsyms] [k] net_rx_action | + 16.25% 0.43% swapper [kernel.kallsyms] [k] be_poll | + 14.74% 0.21% swapper [kernel.kallsyms] [k] be_process_rx | + 13.61% 0.07% swapper [kernel.kallsyms] [k] napi_gro_frags | + 12.58% 0.04% swapper [kernel.kallsyms] [k] netif_receive_skb_internal | + 12.48% 0.03% swapper [kernel.kallsyms] [k] __netif_receive_skb | + 12.42% 0.24% swapper [kernel.kallsyms] [k] __netif_receive_skb_core | + 12.41% 0.00% apache2 [unknown] [k] 0x7f27983b5028 | + 12.41% 0.00% apache2 [unknown] [k] 0x7f2798369028 | + 11.49% 0.16% swapper [kernel.kallsyms] [k] ip_rcv | + 11.29% 0.09% swapper [kernel.kallsyms] [k] ip_rcv_finish | + 10.77% 0.05% swapper [kernel.kallsyms] [k] ip_local_deliver | + 10.70% 0.06% swapper [kernel.kallsyms] [k] ip_local_deliver_finish | + 10.55% 0.22% swapper [kernel.kallsyms] [k] tcp_v4_rcv | + 10.10% 0.00% apache2 [unknown] [k] | + 10.01% 0.04% swapper [kernel.kallsyms] [k] tcp_v4_do_rcv Expanding in a few of those, you'll see: | - 55.24% 0.20% swapper [kernel.kallsyms] [k] cpu_startup_entry |- 55.04% cpu_startup_entry | - 52.98% call_cpuidle | + 52.93% cpuidle_enter | + 0.00% ret_from_intr |0.00% cpuidle_enter_state |0.00% irq_entries_start | + 1.14% cpuidle_select | + 0.47% schedule_preempt_disabled | 0.10% rcu_idle_enter | 0.09% rcu_idle_exit | + 0.05% ret_from_intr | + 0.05% tick_nohz_idle_enter | + 0.04% arch_cpu_idle_enter | 0.02% cpuidle_enter | 0.02% tick_check_broadcast_expired | + 0.01% cpuidle_reflect | 0.01% menu_reflect | 0.01% atomic_notifier_call_chain | 0.01% local_touch_nmi | 0.01% cpuidle_not_available | 0.01% menu_select | 0.01% cpuidle_get_cpu_driver | + 0.01% tick_nohz_idle_exit | + 0.01% sched_ttwu_pending | 0.00% set_cpu_sd_state_idle | 0.00% native_irq_return_iret | 0.00% schedule | + 0.00% arch_cpu_idle_exit | 0.00% __tick_nohz_idle_e
[Group.of.nepali.translators] [Bug 1579278] Re: Consider changing default CPU frequency scaling governor back to "performance" (Ubuntu Server)
The default is already CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y. However, it can be changed from user space. I suggest looking at /etc/init.d/ondemand ** Changed in: linux (Ubuntu Xenial) Status: Triaged => Invalid -- You received this bug notification because you are a member of नेपाली भाषा समायोजकहरुको समूह, which is subscribed to Xenial. Matching subscriptions: Ubuntu 16.04 Bugs https://bugs.launchpad.net/bugs/1579278 Title: Consider changing default CPU frequency scaling governor back to "performance" (Ubuntu Server) Status in linux package in Ubuntu: Invalid Status in linux source package in Xenial: Invalid Bug description: Hi, With the new Ubuntu archive servers, we saw constantly high load and after some tinkering, we found that it was mostly CPUs being woken up to see if they should enter idle states. Changing the CPU frequency scaling governor to "performance" saw a considerable drop. Perf report using the following commands: | perf record -g -a sleep 10 | perf report | Samples: 287K of event 'cycles:pp', Event count (approx.): 124776998906 | Children Self Command Shared Object Symbol | + 55.24% 0.20% swapper [kernel.kallsyms] [k] cpu_startup_entry | + 53.51% 0.00% swapper [kernel.kallsyms] [k] start_secondary | + 53.02% 0.08% swapper [kernel.kallsyms] [k] call_cpuidle | + 52.94% 0.02% swapper [kernel.kallsyms] [k] cpuidle_enter | + 31.81% 0.67% swapper [kernel.kallsyms] [k] cpuidle_enter_state | + 29.59% 0.12% swapper [kernel.kallsyms] [k] acpi_idle_enter | + 29.45% 0.05% swapper [kernel.kallsyms] [k] acpi_idle_do_entry | + 29.43%29.43% swapper [kernel.kallsyms] [k] acpi_processor_ffh_cstate_enter | + 20.51% 0.04% swapper [kernel.kallsyms] [k] ret_from_intr | + 20.47% 0.12% swapper [kernel.kallsyms] [k] do_IRQ | + 19.30% 0.07% swapper [kernel.kallsyms] [k] irq_exit | + 19.18% 0.07% apache2 [kernel.kallsyms] [k] entry_SYSCALL_64_fastpath | + 18.80% 0.17% swapper [kernel.kallsyms] [k] __do_softirq | + 16.45% 0.11% swapper [kernel.kallsyms] [k] net_rx_action | + 16.25% 0.43% swapper [kernel.kallsyms] [k] be_poll | + 14.74% 0.21% swapper [kernel.kallsyms] [k] be_process_rx | + 13.61% 0.07% swapper [kernel.kallsyms] [k] napi_gro_frags | + 12.58% 0.04% swapper [kernel.kallsyms] [k] netif_receive_skb_internal | + 12.48% 0.03% swapper [kernel.kallsyms] [k] __netif_receive_skb | + 12.42% 0.24% swapper [kernel.kallsyms] [k] __netif_receive_skb_core | + 12.41% 0.00% apache2 [unknown] [k] 0x7f27983b5028 | + 12.41% 0.00% apache2 [unknown] [k] 0x7f2798369028 | + 11.49% 0.16% swapper [kernel.kallsyms] [k] ip_rcv | + 11.29% 0.09% swapper [kernel.kallsyms] [k] ip_rcv_finish | + 10.77% 0.05% swapper [kernel.kallsyms] [k] ip_local_deliver | + 10.70% 0.06% swapper [kernel.kallsyms] [k] ip_local_deliver_finish | + 10.55% 0.22% swapper [kernel.kallsyms] [k] tcp_v4_rcv | + 10.10% 0.00% apache2 [unknown] [k] | + 10.01% 0.04% swapper [kernel.kallsyms] [k] tcp_v4_do_rcv Expanding in a few of those, you'll see: | - 55.24% 0.20% swapper [kernel.kallsyms] [k] cpu_startup_entry |- 55.04% cpu_startup_entry | - 52.98% call_cpuidle | + 52.93% cpuidle_enter | + 0.00% ret_from_intr |0.00% cpuidle_enter_state |0.00% irq_entries_start | + 1.14% cpuidle_select | + 0.47% schedule_preempt_disabled | 0.10% rcu_idle_enter | 0.09% rcu_idle_exit | + 0.05% ret_from_intr | + 0.05% tick_nohz_idle_enter | + 0.04% arch_cpu_idle_enter | 0.02% cpuidle_enter | 0.02% tick_check_broadcast_expired | + 0.01% cpuidle_reflect | 0.01% menu_reflect | 0.01% atomic_notifier_call_chain | 0.01% local_touch_nmi | 0.01% cpuidle_not_available | 0.01% menu_select | 0.01% cpuidle_get_cpu_driver | + 0.01% tick_nohz_idle_exit | + 0.01% sched_ttwu_pending | 0.00% set_cpu_sd_state_idle | 0.00% native_irq_return_iret | 0.00% schedule | + 0.00% arch_cpu_idle_exit | 0.00% __tick_nohz
[Group.of.nepali.translators] [Bug 1579278] Re: Consider changing default CPU frequency scaling governor back to "performance"
As Theodore Ts'o has pointed out[1]: """ ... with modern Intel processors, the ondemand CPU governor is actually counterproductive because waking up to decide whether the CPU is idle keeps it from entering the deepest sleep states, and so (somewhat counterintuitively) the performance governor will actually result in the best battery life. """ [1]https://plus.google.com/+TheodoreTso/posts/2vEekAsG2QT ** Also affects: linux (Ubuntu Xenial) Importance: Undecided Status: New -- You received this bug notification because you are a member of नेपाली भाषा समायोजकहरुको समूह, which is subscribed to Xenial. Matching subscriptions: Ubuntu 16.04 Bugs https://bugs.launchpad.net/bugs/1579278 Title: Consider changing default CPU frequency scaling governor back to "performance" Status in linux package in Ubuntu: Incomplete Status in linux source package in Xenial: Incomplete Bug description: Hi, With the new Ubuntu archive servers, we saw constantly high load and after some tinkering, we found that it was mostly CPUs being woken up to see if they should enter idle states. Changing the CPU frequency scaling governor to "performance" saw a considerable drop. Perf report using the following commands: | perf record -g -a sleep 10 | perf report | Samples: 287K of event 'cycles:pp', Event count (approx.): 124776998906 | Children Self Command Shared Object Symbol | + 55.24% 0.20% swapper [kernel.kallsyms] [k] cpu_startup_entry | + 53.51% 0.00% swapper [kernel.kallsyms] [k] start_secondary | + 53.02% 0.08% swapper [kernel.kallsyms] [k] call_cpuidle | + 52.94% 0.02% swapper [kernel.kallsyms] [k] cpuidle_enter | + 31.81% 0.67% swapper [kernel.kallsyms] [k] cpuidle_enter_state | + 29.59% 0.12% swapper [kernel.kallsyms] [k] acpi_idle_enter | + 29.45% 0.05% swapper [kernel.kallsyms] [k] acpi_idle_do_entry | + 29.43%29.43% swapper [kernel.kallsyms] [k] acpi_processor_ffh_cstate_enter | + 20.51% 0.04% swapper [kernel.kallsyms] [k] ret_from_intr | + 20.47% 0.12% swapper [kernel.kallsyms] [k] do_IRQ | + 19.30% 0.07% swapper [kernel.kallsyms] [k] irq_exit | + 19.18% 0.07% apache2 [kernel.kallsyms] [k] entry_SYSCALL_64_fastpath | + 18.80% 0.17% swapper [kernel.kallsyms] [k] __do_softirq | + 16.45% 0.11% swapper [kernel.kallsyms] [k] net_rx_action | + 16.25% 0.43% swapper [kernel.kallsyms] [k] be_poll | + 14.74% 0.21% swapper [kernel.kallsyms] [k] be_process_rx | + 13.61% 0.07% swapper [kernel.kallsyms] [k] napi_gro_frags | + 12.58% 0.04% swapper [kernel.kallsyms] [k] netif_receive_skb_internal | + 12.48% 0.03% swapper [kernel.kallsyms] [k] __netif_receive_skb | + 12.42% 0.24% swapper [kernel.kallsyms] [k] __netif_receive_skb_core | + 12.41% 0.00% apache2 [unknown] [k] 0x7f27983b5028 | + 12.41% 0.00% apache2 [unknown] [k] 0x7f2798369028 | + 11.49% 0.16% swapper [kernel.kallsyms] [k] ip_rcv | + 11.29% 0.09% swapper [kernel.kallsyms] [k] ip_rcv_finish | + 10.77% 0.05% swapper [kernel.kallsyms] [k] ip_local_deliver | + 10.70% 0.06% swapper [kernel.kallsyms] [k] ip_local_deliver_finish | + 10.55% 0.22% swapper [kernel.kallsyms] [k] tcp_v4_rcv | + 10.10% 0.00% apache2 [unknown] [k] | + 10.01% 0.04% swapper [kernel.kallsyms] [k] tcp_v4_do_rcv Expanding in a few of those, you'll see: | - 55.24% 0.20% swapper [kernel.kallsyms] [k] cpu_startup_entry |- 55.04% cpu_startup_entry | - 52.98% call_cpuidle | + 52.93% cpuidle_enter | + 0.00% ret_from_intr |0.00% cpuidle_enter_state |0.00% irq_entries_start | + 1.14% cpuidle_select | + 0.47% schedule_preempt_disabled | 0.10% rcu_idle_enter | 0.09% rcu_idle_exit | + 0.05% ret_from_intr | + 0.05% tick_nohz_idle_enter | + 0.04% arch_cpu_idle_enter | 0.02% cpuidle_enter | 0.02% tick_check_broadcast_expired | + 0.01% cpuidle_reflect | 0.01% menu_reflect | 0.01% atomic_notifier_call_chain | 0.01% local_touch_nmi | 0.01% cpuidle_not_available | 0.01% menu_select | 0.01% cpuidle_get_cp