@fish : Yes your issue does not belong here. To figure out where your issue actually belongs, some details are missing:
If your stuck at low frequency issue only occurs after a suspend and on battery power, then your issue is covered by: https://bugzilla.kernel.org/show_bug.cgi?id=90041 (and it is not resolved quite yet, even though that is the status). If your issue always occurs and you are not using the proper Dell AC adapter, then that is why. Otherwise, I don't know. Try the acpi_cpufreq CPU frequency scaling driver instead. Also have a look at: https://bugzilla.kernel.org/show_bug.cgi?id=189861 ** Bug watch added: Linux Kernel Bug Tracker #90041 http://bugzilla.kernel.org/show_bug.cgi?id=90041 ** Bug watch added: Linux Kernel Bug Tracker #189861 http://bugzilla.kernel.org/show_bug.cgi?id=189861 -- 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/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: Fix Released 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] 0x00007f27983b5028 | + 12.41% 0.00% apache2 [unknown] [k] 0x00007f2798369028 | + 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] 0000000000000000 | + 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_enter | 0.00% irq_entries_start | 0.00% sched_clock_idle_wakeup_event | 0.00% reschedule_interrupt | + 0.00% apic_timer_interrupt | + 0.20% start_secondary | + 0.00% x86_64_start_kernel | + 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 | - 52.92% cpuidle_enter | + 31.81% cpuidle_enter_state | + 20.01% ret_from_intr | + 0.51% apic_timer_interrupt | 0.28% native_irq_return_iret | + 0.09% reschedule_interrupt | 0.05% irq_entries_start | 0.05% do_IRQ | 0.05% common_interrupt | 0.02% sched_idle_set_state | 0.01% acpi_idle_enter | 0.01% ktime_get | 0.01% restore_regs_and_iret | 0.01% restore_c_regs_and_iret | + 0.01% call_function_single_interrupt | 0.00% native_iret | + 0.00% call_function_interrupt | 0.00% smp_apic_timer_interrupt | 0.00% smp_reschedule_interrupt | 0.00% smp_call_function_single_interrupt | + 0.02% start_secondary To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1579278/+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
