我的cpu在一段时间后减速并且没有恢复
有时，我无法重现它（但它经常发生 – 至少每周几次）我的cpu减慢到低于规定的最小值。 这是一分钟前的cpufreq-info输出示例：
cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009 Report errors and bugs to cpufreq@vger.kernel.org, please. analyzing CPU 0: driver: intel_pstate CPUs which run at the same hardware frequency: 0 CPUs which need to have their frequency coordinated by software: 0 maximum transition latency: 0.97 ms. hardware limits: 800 MHz - 3.30 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 800 MHz and 3.30 GHz. The governor "powersave" may decide which speed to use within this range. current CPU frequency is 610 MHz. analyzing CPU 1: driver: intel_pstate CPUs which run at the same hardware frequency: 1 CPUs which need to have their frequency coordinated by software: 1 maximum transition latency: 0.97 ms. hardware limits: 800 MHz - 3.30 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 800 MHz and 3.30 GHz. The governor "powersave" may decide which speed to use within this range. current CPU frequency is 615 MHz. analyzing CPU 2: driver: intel_pstate CPUs which run at the same hardware frequency: 2 CPUs which need to have their frequency coordinated by software: 2 maximum transition latency: 0.97 ms. hardware limits: 800 MHz - 3.30 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 800 MHz and 3.30 GHz. The governor "powersave" may decide which speed to use within this range. current CPU frequency is 590 MHz. analyzing CPU 3: driver: intel_pstate CPUs which run at the same hardware frequency: 3 CPUs which need to have their frequency coordinated by software: 3 maximum transition latency: 0.97 ms. hardware limits: 800 MHz - 3.30 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 800 MHz and 3.30 GHz. The governor "powersave" may decide which speed to use within this range. current CPU frequency is 589 MHz.
问题是它确实减慢了一切。 Firefox变慢，vim的启动时间从150到250ms增加到700ms以上， g++编译速度变慢了三倍等等。
重启修复一切。
从我的系统日志过去几个小时的一些错误行：
May 17 16:10:53 lati kernel: [ 1421.872755] ACPI Error: Index value 0x0000000000000083 overflows field width 0x7 (20140424/exfldio-343) May 17 16:10:53 lati kernel: [ 1421.872758] ACPI Error: Method parse/execution failed [\NEVT] (Node ffff88040e047258), AE_AML_REGISTER_LIMIT (20140424/psparse-536) May 17 16:10:53 lati kernel: [ 1421.872761] ACPI Error: Method parse/execution failed [\_SB_.PCI0.LPCB.ECDV._Q66] (Node ffff88040e044b90), AE_AML_REGISTER_LIMIT (20140424/psparse-536) May 17 16:10:56 lati kernel: [ 1425.907749] ACPI Error: Index value 0x0000000000000083 overflows field width 0x7 (20140424/exfldio-343) May 17 16:10:56 lati kernel: [ 1425.907765] ACPI Error: Method parse/execution failed [\NEVT] (Node ffff88040e047258), AE_AML_REGISTER_LIMIT (20140424/psparse-536) May 17 16:10:56 lati kernel: [ 1425.907794] ACPI Error: Method parse/execution failed [\_SB_.PCI0.LPCB.ECDV._Q66] (Node ffff88040e044b90), AE_AML_REGISTER_LIMIT (20140424/psparse-536) May 17 16:12:09 lati kernel: [ 1.925333] EXT4-fs (sda5): re-mounted. Opts: errors=remount-ro May 17 16:12:09 lati kernel: [ 2.421037] systemd-udevd[331]: Error calling EVIOCSKEYCODE: Invalid argument May 17 16:12:21 lati gnome-session[2251]: WARNING: Could not parse desktop file tracker-store.desktop or it references a not found TryExec binary May 17 16:12:21 lati gnome-session[2251]: WARNING: Could not parse desktop file tracker-miner-fs.desktop or it references a not found TryExec binary May 17 16:12:51 lati gnome-session[2251]: GLib-CRITICAL: g_environ_setenv: assertion 'value != NULL' failed May 17 17:48:19 lati kernel: [ 5769.576717] systemd-hostnamed[6983]: Warning: nss-myhostname is not installed. Changing the local hostname might make it unresolveable. Please install nss-myhostname!
我在戴尔E7440，bios版本A14上使用Ubuntu 14.04.2，全新安装，64位。
顺便说一句，即使执行lsb_release ，当我处于这种模式时，也需要大约400ms。
额外信息
- 我的处理器型号名称：Intel（R）Core（TM）i7-4600U CPU @ 2.10GHz
- 我的处理器型号：69
- 它可能只在暂停后发生，但通常不会发生（例如，自从我提出这个问题以来，它只发生过一次）。
额外信息（2）
grep -r . *输出grep -r . * grep -r . * in /sys/class/thermal ：
cooling_device0/type:Processor cooling_device0/power/control:auto cooling_device0/power/async:disabled cooling_device0/power/runtime_enabled:disabled cooling_device0/power/runtime_active_kids:0 cooling_device0/power/runtime_active_time:0 cooling_device0/power/runtime_status:unsupported cooling_device0/power/runtime_usage:0 cooling_device0/power/runtime_suspended_time:0 cooling_device0/cur_state:0 cooling_device0/max_state:3 cooling_device1/type:Processor cooling_device1/power/control:auto cooling_device1/power/async:disabled cooling_device1/power/runtime_enabled:disabled cooling_device1/power/runtime_active_kids:0 cooling_device1/power/runtime_active_time:0 cooling_device1/power/runtime_status:unsupported cooling_device1/power/runtime_usage:0 cooling_device1/power/runtime_suspended_time:0 cooling_device1/cur_state:0 cooling_device1/max_state:3 cooling_device2/type:Processor cooling_device2/power/control:auto cooling_device2/power/async:disabled cooling_device2/power/runtime_enabled:disabled cooling_device2/power/runtime_active_kids:0 cooling_device2/power/runtime_active_time:0 cooling_device2/power/runtime_status:unsupported cooling_device2/power/runtime_usage:0 cooling_device2/power/runtime_suspended_time:0 cooling_device2/cur_state:0 cooling_device2/max_state:3 cooling_device3/type:Processor cooling_device3/power/control:auto cooling_device3/power/async:disabled cooling_device3/power/runtime_enabled:disabled cooling_device3/power/runtime_active_kids:0 cooling_device3/power/runtime_active_time:0 cooling_device3/power/runtime_status:unsupported cooling_device3/power/runtime_usage:0 cooling_device3/power/runtime_suspended_time:0 cooling_device3/cur_state:0 cooling_device3/max_state:3 cooling_device4/type:intel_powerclamp cooling_device4/power/control:auto cooling_device4/power/async:disabled cooling_device4/power/runtime_enabled:disabled cooling_device4/power/runtime_active_kids:0 cooling_device4/power/runtime_active_time:0 cooling_device4/power/runtime_status:unsupported cooling_device4/power/runtime_usage:0 cooling_device4/power/runtime_suspended_time:0 cooling_device4/cur_state:-1 cooling_device4/max_state:50 thermal_zone0/mode:enabled thermal_zone0/temp:25000 thermal_zone0/type:acpitz thermal_zone0/power/control:auto thermal_zone0/power/async:disabled thermal_zone0/power/runtime_enabled:disabled thermal_zone0/power/runtime_active_kids:0 thermal_zone0/power/runtime_active_time:0 thermal_zone0/power/runtime_status:unsupported thermal_zone0/power/runtime_usage:0 thermal_zone0/power/runtime_suspended_time:0 thermal_zone0/trip_point_0_temp:107000 thermal_zone0/trip_point_0_type:critical thermal_zone0/policy:step_wise thermal_zone0/passive:0 thermal_zone1/temp:47000 thermal_zone1/type:x86_pkg_temp thermal_zone1/power/control:auto thermal_zone1/power/async:disabled thermal_zone1/power/runtime_enabled:disabled thermal_zone1/power/runtime_active_kids:0 thermal_zone1/power/runtime_active_time:0 thermal_zone1/power/runtime_status:unsupported thermal_zone1/power/runtime_usage:0 thermal_zone1/power/runtime_suspended_time:0 thermal_zone1/trip_point_0_temp:0 thermal_zone1/trip_point_0_type:passive thermal_zone1/trip_point_1_temp:0 thermal_zone1/trip_point_1_type:passive thermal_zone1/policy:step_wise
问题是否仍然存在？
我急切地想要确认或否认我认为正在发生的事情。
在暂停时钟调制已启用后，该理论以某种方式（怀疑是BIOS问题）。 当前版本的intel_pstate驱动程序与任何时钟调制的使用都不兼容，无论负载如何，总是会将目标pstate驱动到最小。 结果是表观CPU频率保持在最小*调制百分比。 acpi-cpufreq驱动程序与时钟调制一起工作正常，从而产生所需的频率*调制百分比。 （即acpi-cpufreq驱动程序的问题不太明显。）
请进行以下测试：
1.）（每次启动需要一次）
sudo modprobe msr
2.）在暂停之前：
sudo rdmsr -a 0x19a
3.）暂停后导致CPU频率低：
sudo rdmsr -a 0x19a
4.）如果步骤3的结果不是0，则：
sudo wrmsr -a 0x19a 0x0
并检查它：
sudo rdmsr -a 0x19a
5.）现在CPU频率是否正常？
在这里回复所有输出。
注意：rdmsr和wrmsr包含在msr-tools包中，如果默认安装，我不记得。
编辑：
如果可以的话，关于热交互和pstates的英特尔主题专家也希望输出：
cd /sys/class/thermal grep -r . *