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What: /sys/devices/system/cpu/ |
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Date: pre-git history |
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Contact: Linux kernel mailing list <[email protected]> |
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Description: |
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A collection of both global and individual CPU attributes |
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Individual CPU attributes are contained in subdirectories |
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named by the kernel's logical CPU number, e.g.: |
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/sys/devices/system/cpu/cpu#/ |
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What: /sys/devices/system/cpu/kernel_max |
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/sys/devices/system/cpu/offline |
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/sys/devices/system/cpu/online |
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/sys/devices/system/cpu/possible |
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/sys/devices/system/cpu/present |
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Date: December 2008 |
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Contact: Linux kernel mailing list <[email protected]> |
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Description: CPU topology files that describe kernel limits related to |
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hotplug. Briefly: |
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kernel_max: the maximum cpu index allowed by the kernel |
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configuration. |
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offline: cpus that are not online because they have been |
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HOTPLUGGED off or exceed the limit of cpus allowed by the |
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kernel configuration (kernel_max above). |
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online: cpus that are online and being scheduled. |
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possible: cpus that have been allocated resources and can be |
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brought online if they are present. |
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present: cpus that have been identified as being present in |
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the system. |
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See Documentation/admin-guide/cputopology.rst for more information. |
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What: /sys/devices/system/cpu/probe |
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/sys/devices/system/cpu/release |
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Date: November 2009 |
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Contact: Linux kernel mailing list <[email protected]> |
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Description: Dynamic addition and removal of CPU's. This is not hotplug |
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removal, this is meant complete removal/addition of the CPU |
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from the system. |
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probe: writes to this file will dynamically add a CPU to the |
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system. Information written to the file to add CPU's is |
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architecture specific. |
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release: writes to this file dynamically remove a CPU from |
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the system. Information written to the file to remove CPU's |
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is architecture specific. |
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What: /sys/devices/system/cpu/cpu#/node |
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Date: October 2009 |
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Contact: Linux memory management mailing list <[email protected]> |
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Description: Discover NUMA node a CPU belongs to |
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When CONFIG_NUMA is enabled, a symbolic link that points |
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to the corresponding NUMA node directory. |
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For example, the following symlink is created for cpu42 |
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in NUMA node 2: |
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/sys/devices/system/cpu/cpu42/node2 -> ../../node/node2 |
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What: /sys/devices/system/cpu/cpu#/topology/core_id |
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/sys/devices/system/cpu/cpu#/topology/core_siblings |
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/sys/devices/system/cpu/cpu#/topology/core_siblings_list |
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/sys/devices/system/cpu/cpu#/topology/physical_package_id |
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/sys/devices/system/cpu/cpu#/topology/thread_siblings |
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/sys/devices/system/cpu/cpu#/topology/thread_siblings_list |
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Date: December 2008 |
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Contact: Linux kernel mailing list <[email protected]> |
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Description: CPU topology files that describe a logical CPU's relationship |
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to other cores and threads in the same physical package. |
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One cpu# directory is created per logical CPU in the system, |
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e.g. /sys/devices/system/cpu/cpu42/. |
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Briefly, the files above are: |
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core_id: the CPU core ID of cpu#. Typically it is the |
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hardware platform's identifier (rather than the kernel's). |
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The actual value is architecture and platform dependent. |
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core_siblings: internal kernel map of cpu#'s hardware threads |
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within the same physical_package_id. |
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core_siblings_list: human-readable list of the logical CPU |
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numbers within the same physical_package_id as cpu#. |
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physical_package_id: physical package id of cpu#. Typically |
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corresponds to a physical socket number, but the actual value |
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is architecture and platform dependent. |
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thread_siblings: internal kernel map of cpu#'s hardware |
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threads within the same core as cpu# |
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thread_siblings_list: human-readable list of cpu#'s hardware |
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threads within the same core as cpu# |
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See Documentation/admin-guide/cputopology.rst for more information. |
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What: /sys/devices/system/cpu/cpuidle/available_governors |
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/sys/devices/system/cpu/cpuidle/current_driver |
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/sys/devices/system/cpu/cpuidle/current_governor |
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/sys/devices/system/cpu/cpuidle/current_governer_ro |
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Date: September 2007 |
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Contact: Linux kernel mailing list <[email protected]> |
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Description: Discover cpuidle policy and mechanism |
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Various CPUs today support multiple idle levels that are |
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differentiated by varying exit latencies and power |
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consumption during idle. |
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Idle policy (governor) is differentiated from idle mechanism |
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(driver). |
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available_governors: (RO) displays a space separated list of |
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available governors. |
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current_driver: (RO) displays current idle mechanism. |
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current_governor: (RW) displays current idle policy. Users can |
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switch the governor at runtime by writing to this file. |
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current_governor_ro: (RO) displays current idle policy. |
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See Documentation/admin-guide/pm/cpuidle.rst and |
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Documentation/driver-api/pm/cpuidle.rst for more information. |
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What: /sys/devices/system/cpu/cpuX/cpuidle/stateN/name |
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/sys/devices/system/cpu/cpuX/cpuidle/stateN/latency |
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/sys/devices/system/cpu/cpuX/cpuidle/stateN/power |
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/sys/devices/system/cpu/cpuX/cpuidle/stateN/time |
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/sys/devices/system/cpu/cpuX/cpuidle/stateN/usage |
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/sys/devices/system/cpu/cpuX/cpuidle/stateN/above |
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/sys/devices/system/cpu/cpuX/cpuidle/stateN/below |
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Date: September 2007 |
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KernelVersion: v2.6.24 |
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Contact: Linux power management list <[email protected]> |
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Description: |
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The directory /sys/devices/system/cpu/cpuX/cpuidle contains per |
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logical CPU specific cpuidle information for each online cpu X. |
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The processor idle states which are available for use have the |
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following attributes: |
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======== ==== ================================================= |
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name: (RO) Name of the idle state (string). |
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latency: (RO) The latency to exit out of this idle state (in |
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microseconds). |
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power: (RO) The power consumed while in this idle state (in |
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milliwatts). |
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time: (RO) The total time spent in this idle state |
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(in microseconds). |
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usage: (RO) Number of times this state was entered (a count). |
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above: (RO) Number of times this state was entered, but the |
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observed CPU idle duration was too short for it |
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(a count). |
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below: (RO) Number of times this state was entered, but the |
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observed CPU idle duration was too long for it |
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(a count). |
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======== ==== ================================================= |
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What: /sys/devices/system/cpu/cpuX/cpuidle/stateN/desc |
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Date: February 2008 |
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KernelVersion: v2.6.25 |
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Contact: Linux power management list <[email protected]> |
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Description: |
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(RO) A small description about the idle state (string). |
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What: /sys/devices/system/cpu/cpuX/cpuidle/stateN/disable |
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Date: March 2012 |
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KernelVersion: v3.10 |
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Contact: Linux power management list <[email protected]> |
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Description: |
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(RW) Option to disable this idle state (bool). The behavior and |
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the effect of the disable variable depends on the implementation |
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of a particular governor. In the ladder governor, for example, |
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it is not coherent, i.e. if one is disabling a light state, then |
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all deeper states are disabled as well, but the disable variable |
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does not reflect it. Likewise, if one enables a deep state but a |
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lighter state still is disabled, then this has no effect. |
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What: /sys/devices/system/cpu/cpuX/cpuidle/stateN/default_status |
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Date: December 2019 |
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KernelVersion: v5.6 |
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Contact: Linux power management list <[email protected]> |
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Description: |
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(RO) The default status of this state, "enabled" or "disabled". |
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What: /sys/devices/system/cpu/cpuX/cpuidle/stateN/residency |
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Date: March 2014 |
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KernelVersion: v3.15 |
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Contact: Linux power management list <[email protected]> |
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Description: |
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(RO) Display the target residency i.e. the minimum amount of |
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time (in microseconds) this cpu should spend in this idle state |
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to make the transition worth the effort. |
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What: /sys/devices/system/cpu/cpuX/cpuidle/stateN/s2idle/ |
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Date: March 2018 |
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KernelVersion: v4.17 |
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Contact: Linux power management list <[email protected]> |
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Description: |
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Idle state usage statistics related to suspend-to-idle. |
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This attribute group is only present for states that can be |
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used in suspend-to-idle with suspended timekeeping. |
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What: /sys/devices/system/cpu/cpuX/cpuidle/stateN/s2idle/time |
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Date: March 2018 |
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KernelVersion: v4.17 |
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Contact: Linux power management list <[email protected]> |
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Description: |
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Total time spent by the CPU in suspend-to-idle (with scheduler |
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tick suspended) after requesting this state. |
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What: /sys/devices/system/cpu/cpuX/cpuidle/stateN/s2idle/usage |
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Date: March 2018 |
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KernelVersion: v4.17 |
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Contact: Linux power management list <[email protected]> |
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Description: |
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Total number of times this state has been requested by the CPU |
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while entering suspend-to-idle. |
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What: /sys/devices/system/cpu/cpu#/cpufreq/* |
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Date: pre-git history |
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Contact: [email protected] |
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Description: Discover and change clock speed of CPUs |
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Clock scaling allows you to change the clock speed of the |
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CPUs on the fly. This is a nice method to save battery |
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power, because the lower the clock speed, the less power |
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the CPU consumes. |
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There are many knobs to tweak in this directory. |
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See files in Documentation/cpu-freq/ for more information. |
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What: /sys/devices/system/cpu/cpu#/cpufreq/freqdomain_cpus |
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Date: June 2013 |
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Contact: [email protected] |
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Description: Discover CPUs in the same CPU frequency coordination domain |
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freqdomain_cpus is the list of CPUs (online+offline) that share |
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the same clock/freq domain (possibly at the hardware level). |
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That information may be hidden from the cpufreq core and the |
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value of related_cpus may be different from freqdomain_cpus. This |
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attribute is useful for user space DVFS controllers to get better |
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power/performance results for platforms using acpi-cpufreq. |
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This file is only present if the acpi-cpufreq or the cppc-cpufreq |
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drivers are in use. |
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What: /sys/devices/system/cpu/cpu*/cache/index3/cache_disable_{0,1} |
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Date: August 2008 |
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KernelVersion: 2.6.27 |
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Contact: Linux kernel mailing list <[email protected]> |
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Description: Disable L3 cache indices |
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These files exist in every CPU's cache/index3 directory. Each |
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cache_disable_{0,1} file corresponds to one disable slot which |
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can be used to disable a cache index. Reading from these files |
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on a processor with this functionality will return the currently |
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disabled index for that node. There is one L3 structure per |
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node, or per internal node on MCM machines. Writing a valid |
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index to one of these files will cause the specified cache |
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index to be disabled. |
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All AMD processors with L3 caches provide this functionality. |
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For details, see BKDGs at |
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https://www.amd.com/en/support/tech-docs?keyword=bios+kernel |
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What: /sys/devices/system/cpu/cpufreq/boost |
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Date: August 2012 |
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Contact: Linux kernel mailing list <[email protected]> |
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Description: Processor frequency boosting control |
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This switch controls the boost setting for the whole system. |
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Boosting allows the CPU and the firmware to run at a frequency |
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beyond it's nominal limit. |
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More details can be found in |
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Documentation/admin-guide/pm/cpufreq.rst |
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What: /sys/devices/system/cpu/cpu#/crash_notes |
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/sys/devices/system/cpu/cpu#/crash_notes_size |
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Date: April 2013 |
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Contact: [email protected] |
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Description: address and size of the percpu note. |
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crash_notes: the physical address of the memory that holds the |
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note of cpu#. |
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crash_notes_size: size of the note of cpu#. |
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What: /sys/devices/system/cpu/intel_pstate/max_perf_pct |
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/sys/devices/system/cpu/intel_pstate/min_perf_pct |
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/sys/devices/system/cpu/intel_pstate/no_turbo |
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Date: February 2013 |
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Contact: [email protected] |
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Description: Parameters for the Intel P-state driver |
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Logic for selecting the current P-state in Intel |
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Sandybridge+ processors. The three knobs control |
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limits for the P-state that will be requested by the |
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driver. |
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max_perf_pct: limits the maximum P state that will be requested by |
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the driver stated as a percentage of the available performance. |
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min_perf_pct: limits the minimum P state that will be requested by |
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the driver stated as a percentage of the available performance. |
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no_turbo: limits the driver to selecting P states below the turbo |
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frequency range. |
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More details can be found in |
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Documentation/admin-guide/pm/intel_pstate.rst |
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What: /sys/devices/system/cpu/cpu*/cache/index*/<set_of_attributes_mentioned_below> |
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Date: July 2014(documented, existed before August 2008) |
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Contact: Sudeep Holla <[email protected]> |
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Linux kernel mailing list <[email protected]> |
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Description: Parameters for the CPU cache attributes |
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allocation_policy: |
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- WriteAllocate: |
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allocate a memory location to a cache line |
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on a cache miss because of a write |
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- ReadAllocate: |
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allocate a memory location to a cache line |
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on a cache miss because of a read |
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- ReadWriteAllocate: |
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both writeallocate and readallocate |
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attributes: |
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LEGACY used only on IA64 and is same as write_policy |
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coherency_line_size: |
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the minimum amount of data in bytes that gets |
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transferred from memory to cache |
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level: |
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the cache hierarchy in the multi-level cache configuration |
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number_of_sets: |
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total number of sets in the cache, a set is a |
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collection of cache lines with the same cache index |
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physical_line_partition: |
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number of physical cache line per cache tag |
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shared_cpu_list: |
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the list of logical cpus sharing the cache |
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shared_cpu_map: |
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logical cpu mask containing the list of cpus sharing |
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the cache |
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size: |
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the total cache size in kB |
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type: |
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- Instruction: cache that only holds instructions |
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- Data: cache that only caches data |
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- Unified: cache that holds both data and instructions |
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ways_of_associativity: |
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degree of freedom in placing a particular block |
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of memory in the cache |
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write_policy: |
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- WriteThrough: |
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data is written to both the cache line |
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and to the block in the lower-level memory |
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- WriteBack: |
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data is written only to the cache line and |
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the modified cache line is written to main |
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memory only when it is replaced |
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What: /sys/devices/system/cpu/cpu*/cache/index*/id |
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Date: September 2016 |
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Contact: Linux kernel mailing list <[email protected]> |
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Description: Cache id |
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The id provides a unique number for a specific instance of |
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a cache of a particular type. E.g. there may be a level |
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3 unified cache on each socket in a server and we may |
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assign them ids 0, 1, 2, ... |
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Note that id value can be non-contiguous. E.g. level 1 |
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caches typically exist per core, but there may not be a |
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power of two cores on a socket, so these caches may be |
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numbered 0, 1, 2, 3, 4, 5, 8, 9, 10, ... |
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What: /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats |
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/turbo_stat |
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/sub_turbo_stat |
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/unthrottle |
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/powercap |
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/overtemp |
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/supply_fault |
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/overcurrent |
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/sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/occ_reset |
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Date: March 2016 |
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Contact: Linux kernel mailing list <[email protected]> |
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Linux for PowerPC mailing list <[email protected]> |
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Description: POWERNV CPUFreq driver's frequency throttle stats directory and |
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attributes |
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'cpuX/cpufreq/throttle_stats' directory contains the CPU frequency |
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throttle stat attributes for the chip. The throttle stats of a cpu |
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is common across all the cpus belonging to a chip. Below are the |
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throttle attributes exported in the 'throttle_stats' directory: |
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- turbo_stat : This file gives the total number of times the max |
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frequency is throttled to lower frequency in turbo (at and above |
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nominal frequency) range of frequencies. |
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- sub_turbo_stat : This file gives the total number of times the |
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max frequency is throttled to lower frequency in sub-turbo(below |
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nominal frequency) range of frequencies. |
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- unthrottle : This file gives the total number of times the max |
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frequency is unthrottled after being throttled. |
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- powercap : This file gives the total number of times the max |
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frequency is throttled due to 'Power Capping'. |
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- overtemp : This file gives the total number of times the max |
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frequency is throttled due to 'CPU Over Temperature'. |
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- supply_fault : This file gives the total number of times the |
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max frequency is throttled due to 'Power Supply Failure'. |
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- overcurrent : This file gives the total number of times the |
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max frequency is throttled due to 'Overcurrent'. |
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- occ_reset : This file gives the total number of times the max |
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frequency is throttled due to 'OCC Reset'. |
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The sysfs attributes representing different throttle reasons like |
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powercap, overtemp, supply_fault, overcurrent and occ_reset map to |
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the reasons provided by OCC firmware for throttling the frequency. |
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What: /sys/devices/system/cpu/cpufreq/policyX/throttle_stats |
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/turbo_stat |
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/sub_turbo_stat |
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/unthrottle |
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/powercap |
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/overtemp |
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/supply_fault |
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/overcurrent |
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/sys/devices/system/cpu/cpufreq/policyX/throttle_stats/occ_reset |
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Date: March 2016 |
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Contact: Linux kernel mailing list <[email protected]> |
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Linux for PowerPC mailing list <[email protected]> |
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Description: POWERNV CPUFreq driver's frequency throttle stats directory and |
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attributes |
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'policyX/throttle_stats' directory and all the attributes are same as |
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the /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats directory and |
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attributes which give the frequency throttle information of the chip. |
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What: /sys/devices/system/cpu/cpuX/regs/ |
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/sys/devices/system/cpu/cpuX/regs/identification/ |
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/sys/devices/system/cpu/cpuX/regs/identification/midr_el1 |
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/sys/devices/system/cpu/cpuX/regs/identification/revidr_el1 |
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Date: June 2016 |
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Contact: Linux ARM Kernel Mailing list <[email protected]> |
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Description: AArch64 CPU registers |
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'identification' directory exposes the CPU ID registers for |
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identifying model and revision of the CPU. |
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What: /sys/devices/system/cpu/aarch32_el0 |
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Date: May 2021 |
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Contact: Linux ARM Kernel Mailing list <[email protected]> |
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Description: Identifies the subset of CPUs in the system that can execute |
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AArch32 (32-bit ARM) applications. If present, the same format as |
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/sys/devices/system/cpu/{offline,online,possible,present} is used. |
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If absent, then all or none of the CPUs can execute AArch32 |
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applications and execve() will behave accordingly. |
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What: /sys/devices/system/cpu/cpu#/cpu_capacity |
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Date: December 2016 |
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Contact: Linux kernel mailing list <[email protected]> |
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Description: information about CPUs heterogeneity. |
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cpu_capacity: capacity of cpu#. |
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What: /sys/devices/system/cpu/vulnerabilities |
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/sys/devices/system/cpu/vulnerabilities/meltdown |
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/sys/devices/system/cpu/vulnerabilities/spectre_v1 |
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/sys/devices/system/cpu/vulnerabilities/spectre_v2 |
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/sys/devices/system/cpu/vulnerabilities/spec_store_bypass |
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/sys/devices/system/cpu/vulnerabilities/l1tf |
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/sys/devices/system/cpu/vulnerabilities/mds |
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/sys/devices/system/cpu/vulnerabilities/srbds |
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/sys/devices/system/cpu/vulnerabilities/tsx_async_abort |
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/sys/devices/system/cpu/vulnerabilities/itlb_multihit |
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Date: January 2018 |
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Contact: Linux kernel mailing list <[email protected]> |
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Description: Information about CPU vulnerabilities |
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The files are named after the code names of CPU |
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vulnerabilities. The output of those files reflects the |
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state of the CPUs in the system. Possible output values: |
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================ ============================================== |
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"Not affected" CPU is not affected by the vulnerability |
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"Vulnerable" CPU is affected and no mitigation in effect |
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"Mitigation: $M" CPU is affected and mitigation $M is in effect |
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================ ============================================== |
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See also: Documentation/admin-guide/hw-vuln/index.rst |
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What: /sys/devices/system/cpu/smt |
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/sys/devices/system/cpu/smt/active |
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/sys/devices/system/cpu/smt/control |
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Date: June 2018 |
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Contact: Linux kernel mailing list <[email protected]> |
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Description: Control Symmetric Multi Threading (SMT) |
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|
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active: Tells whether SMT is active (enabled and siblings online) |
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|
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control: Read/write interface to control SMT. Possible |
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values: |
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|
|
================ ========================================= |
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"on" SMT is enabled |
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"off" SMT is disabled |
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"forceoff" SMT is force disabled. Cannot be changed. |
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"notsupported" SMT is not supported by the CPU |
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"notimplemented" SMT runtime toggling is not |
|
implemented for the architecture |
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================ ========================================= |
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|
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If control status is "forceoff" or "notsupported" writes |
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are rejected. |
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What: /sys/devices/system/cpu/cpu#/power/energy_perf_bias |
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Date: March 2019 |
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Contact: [email protected] |
|
Description: Intel Energy and Performance Bias Hint (EPB) |
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|
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EPB for the given CPU in a sliding scale 0 - 15, where a value |
|
of 0 corresponds to a hint preference for highest performance |
|
and a value of 15 corresponds to the maximum energy savings. |
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|
|
In order to change the EPB value for the CPU, write either |
|
a number in the 0 - 15 sliding scale above, or one of the |
|
strings: "performance", "balance-performance", "normal", |
|
"balance-power", "power" (that represent values reflected by |
|
their meaning), to this attribute. |
|
|
|
This attribute is present for all online CPUs supporting the |
|
Intel EPB feature. |
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|
|
What: /sys/devices/system/cpu/umwait_control |
|
/sys/devices/system/cpu/umwait_control/enable_c02 |
|
/sys/devices/system/cpu/umwait_control/max_time |
|
Date: May 2019 |
|
Contact: Linux kernel mailing list <[email protected]> |
|
Description: Umwait control |
|
|
|
enable_c02: Read/write interface to control umwait C0.2 state |
|
Read returns C0.2 state status: |
|
0: C0.2 is disabled |
|
1: C0.2 is enabled |
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|
|
Write 'y' or '1' or 'on' to enable C0.2 state. |
|
Write 'n' or '0' or 'off' to disable C0.2 state. |
|
|
|
The interface is case insensitive. |
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|
|
max_time: Read/write interface to control umwait maximum time |
|
in TSC-quanta that the CPU can reside in either C0.1 |
|
or C0.2 state. The time is an unsigned 32-bit number. |
|
Note that a value of zero means there is no limit. |
|
Low order two bits must be zero. |
|
|
|
What: /sys/devices/system/cpu/svm |
|
Date: August 2019 |
|
Contact: Linux kernel mailing list <[email protected]> |
|
Linux for PowerPC mailing list <[email protected]> |
|
Description: Secure Virtual Machine |
|
|
|
If 1, it means the system is using the Protected Execution |
|
Facility in POWER9 and newer processors. i.e., it is a Secure |
|
Virtual Machine. |
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|
|
What: /sys/devices/system/cpu/cpuX/purr |
|
Date: Apr 2005 |
|
Contact: Linux for PowerPC mailing list <[email protected]> |
|
Description: PURR ticks for this CPU since the system boot. |
|
|
|
The Processor Utilization Resources Register (PURR) is |
|
a 64-bit counter which provides an estimate of the |
|
resources used by the CPU thread. The contents of this |
|
register increases monotonically. This sysfs interface |
|
exposes the number of PURR ticks for cpuX. |
|
|
|
What: /sys/devices/system/cpu/cpuX/spurr |
|
Date: Dec 2006 |
|
Contact: Linux for PowerPC mailing list <[email protected]> |
|
Description: SPURR ticks for this CPU since the system boot. |
|
|
|
The Scaled Processor Utilization Resources Register |
|
(SPURR) is a 64-bit counter that provides a frequency |
|
invariant estimate of the resources used by the CPU |
|
thread. The contents of this register increases |
|
monotonically. This sysfs interface exposes the number |
|
of SPURR ticks for cpuX. |
|
|
|
What: /sys/devices/system/cpu/cpuX/idle_purr |
|
Date: Apr 2020 |
|
Contact: Linux for PowerPC mailing list <[email protected]> |
|
Description: PURR ticks for cpuX when it was idle. |
|
|
|
This sysfs interface exposes the number of PURR ticks |
|
for cpuX when it was idle. |
|
|
|
What: /sys/devices/system/cpu/cpuX/idle_spurr |
|
Date: Apr 2020 |
|
Contact: Linux for PowerPC mailing list <[email protected]> |
|
Description: SPURR ticks for cpuX when it was idle. |
|
|
|
This sysfs interface exposes the number of SPURR ticks |
|
for cpuX when it was idle. |
|
|
|
What: /sys/devices/system/cpu/cpuX/mte_tcf_preferred |
|
Date: July 2021 |
|
Contact: Linux ARM Kernel Mailing list <[email protected]> |
|
Description: Preferred MTE tag checking mode |
|
|
|
When a user program specifies more than one MTE tag checking |
|
mode, this sysfs node is used to specify which mode should |
|
be preferred when scheduling a task on that CPU. Possible |
|
values: |
|
|
|
================ ============================================== |
|
"sync" Prefer synchronous mode |
|
"async" Prefer asynchronous mode |
|
================ ============================================== |
|
|
|
See also: Documentation/arm64/memory-tagging-extension.rst
|
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|