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- What: /sys/devices/system/cpu/
- Date: pre-git history
- Contact: Linux kernel mailing list <[email protected]>
- Description:
- A collection of both global and individual CPU attributes
- Individual CPU attributes are contained in subdirectories
- named by the kernel's logical CPU number, e.g.:
- /sys/devices/system/cpu/cpuX/
- What: /sys/devices/system/cpu/kernel_max
- /sys/devices/system/cpu/offline
- /sys/devices/system/cpu/online
- /sys/devices/system/cpu/possible
- /sys/devices/system/cpu/present
- Date: December 2008
- Contact: Linux kernel mailing list <[email protected]>
- Description: CPU topology files that describe kernel limits related to
- hotplug. Briefly:
- kernel_max: the maximum cpu index allowed by the kernel
- configuration.
- offline: cpus that are not online because they have been
- HOTPLUGGED off or exceed the limit of cpus allowed by the
- kernel configuration (kernel_max above).
- online: cpus that are online and being scheduled.
- possible: cpus that have been allocated resources and can be
- brought online if they are present.
- present: cpus that have been identified as being present in
- the system.
- See Documentation/admin-guide/cputopology.rst for more information.
- What: /sys/devices/system/cpu/probe
- /sys/devices/system/cpu/release
- Date: November 2009
- Contact: Linux kernel mailing list <[email protected]>
- Description: Dynamic addition and removal of CPU's. This is not hotplug
- removal, this is meant complete removal/addition of the CPU
- from the system.
- probe: writes to this file will dynamically add a CPU to the
- system. Information written to the file to add CPU's is
- architecture specific.
- release: writes to this file dynamically remove a CPU from
- the system. Information written to the file to remove CPU's
- is architecture specific.
- What: /sys/devices/system/cpu/cpuX/node
- Date: October 2009
- Contact: Linux memory management mailing list <[email protected]>
- Description: Discover NUMA node a CPU belongs to
- When CONFIG_NUMA is enabled, a symbolic link that points
- to the corresponding NUMA node directory.
- For example, the following symlink is created for cpu42
- in NUMA node 2:
- /sys/devices/system/cpu/cpu42/node2 -> ../../node/node2
- What: /sys/devices/system/cpu/cpuX/topology/core_siblings
- /sys/devices/system/cpu/cpuX/topology/core_siblings_list
- /sys/devices/system/cpu/cpuX/topology/physical_package_id
- /sys/devices/system/cpu/cpuX/topology/thread_siblings
- /sys/devices/system/cpu/cpuX/topology/thread_siblings_list
- /sys/devices/system/cpu/cpuX/topology/ppin
- Date: December 2008
- Contact: Linux kernel mailing list <[email protected]>
- Description: CPU topology files that describe a logical CPU's relationship
- to other cores and threads in the same physical package.
- One cpuX directory is created per logical CPU in the system,
- e.g. /sys/devices/system/cpu/cpu42/.
- Briefly, the files above are:
- core_siblings: internal kernel map of cpuX's hardware threads
- within the same physical_package_id.
- core_siblings_list: human-readable list of the logical CPU
- numbers within the same physical_package_id as cpuX.
- physical_package_id: physical package id of cpuX. Typically
- corresponds to a physical socket number, but the actual value
- is architecture and platform dependent.
- thread_siblings: internal kernel map of cpuX's hardware
- threads within the same core as cpuX
- thread_siblings_list: human-readable list of cpuX's hardware
- threads within the same core as cpuX
- ppin: human-readable Protected Processor Identification
- Number of the socket the cpu# belongs to. There should be
- one per physical_package_id. File is readable only to
- admin.
- See Documentation/admin-guide/cputopology.rst for more information.
- What: /sys/devices/system/cpu/cpuidle/available_governors
- /sys/devices/system/cpu/cpuidle/current_driver
- /sys/devices/system/cpu/cpuidle/current_governor
- /sys/devices/system/cpu/cpuidle/current_governer_ro
- Date: September 2007
- Contact: Linux kernel mailing list <[email protected]>
- Description: Discover cpuidle policy and mechanism
- Various CPUs today support multiple idle levels that are
- differentiated by varying exit latencies and power
- consumption during idle.
- Idle policy (governor) is differentiated from idle mechanism
- (driver).
- available_governors: (RO) displays a space separated list of
- available governors.
- current_driver: (RO) displays current idle mechanism.
- current_governor: (RW) displays current idle policy. Users can
- switch the governor at runtime by writing to this file.
- current_governor_ro: (RO) displays current idle policy.
- See Documentation/admin-guide/pm/cpuidle.rst and
- Documentation/driver-api/pm/cpuidle.rst for more information.
- What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/name
- /sys/devices/system/cpu/cpuX/cpuidle/stateN/latency
- /sys/devices/system/cpu/cpuX/cpuidle/stateN/power
- /sys/devices/system/cpu/cpuX/cpuidle/stateN/time
- /sys/devices/system/cpu/cpuX/cpuidle/stateN/usage
- /sys/devices/system/cpu/cpuX/cpuidle/stateN/above
- /sys/devices/system/cpu/cpuX/cpuidle/stateN/below
- Date: September 2007
- KernelVersion: v2.6.24
- Contact: Linux power management list <[email protected]>
- Description:
- The directory /sys/devices/system/cpu/cpuX/cpuidle contains per
- logical CPU specific cpuidle information for each online cpu X.
- The processor idle states which are available for use have the
- following attributes:
- ======== ==== =================================================
- name: (RO) Name of the idle state (string).
- latency: (RO) The latency to exit out of this idle state (in
- microseconds).
- power: (RO) The power consumed while in this idle state (in
- milliwatts).
- time: (RO) The total time spent in this idle state
- (in microseconds).
- usage: (RO) Number of times this state was entered (a count).
- above: (RO) Number of times this state was entered, but the
- observed CPU idle duration was too short for it
- (a count).
- below: (RO) Number of times this state was entered, but the
- observed CPU idle duration was too long for it
- (a count).
- ======== ==== =================================================
- What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/desc
- Date: February 2008
- KernelVersion: v2.6.25
- Contact: Linux power management list <[email protected]>
- Description:
- (RO) A small description about the idle state (string).
- What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/disable
- Date: March 2012
- KernelVersion: v3.10
- Contact: Linux power management list <[email protected]>
- Description:
- (RW) Option to disable this idle state (bool). The behavior and
- the effect of the disable variable depends on the implementation
- of a particular governor. In the ladder governor, for example,
- it is not coherent, i.e. if one is disabling a light state, then
- all deeper states are disabled as well, but the disable variable
- does not reflect it. Likewise, if one enables a deep state but a
- lighter state still is disabled, then this has no effect.
- What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/default_status
- Date: December 2019
- KernelVersion: v5.6
- Contact: Linux power management list <[email protected]>
- Description:
- (RO) The default status of this state, "enabled" or "disabled".
- What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/residency
- Date: March 2014
- KernelVersion: v3.15
- Contact: Linux power management list <[email protected]>
- Description:
- (RO) Display the target residency i.e. the minimum amount of
- time (in microseconds) this cpu should spend in this idle state
- to make the transition worth the effort.
- What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/s2idle/
- Date: March 2018
- KernelVersion: v4.17
- Contact: Linux power management list <[email protected]>
- Description:
- Idle state usage statistics related to suspend-to-idle.
- This attribute group is only present for states that can be
- used in suspend-to-idle with suspended timekeeping.
- What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/s2idle/time
- Date: March 2018
- KernelVersion: v4.17
- Contact: Linux power management list <[email protected]>
- Description:
- Total time spent by the CPU in suspend-to-idle (with scheduler
- tick suspended) after requesting this state.
- What: /sys/devices/system/cpu/cpuX/cpuidle/state<N>/s2idle/usage
- Date: March 2018
- KernelVersion: v4.17
- Contact: Linux power management list <[email protected]>
- Description:
- Total number of times this state has been requested by the CPU
- while entering suspend-to-idle.
- What: /sys/devices/system/cpu/cpuX/cpufreq/*
- Date: pre-git history
- Contact: [email protected]
- Description: Discover and change clock speed of CPUs
- Clock scaling allows you to change the clock speed of the
- CPUs on the fly. This is a nice method to save battery
- power, because the lower the clock speed, the less power
- the CPU consumes.
- There are many knobs to tweak in this directory.
- See files in Documentation/cpu-freq/ for more information.
- What: /sys/devices/system/cpu/cpuX/cpufreq/freqdomain_cpus
- Date: June 2013
- Contact: [email protected]
- Description: Discover CPUs in the same CPU frequency coordination domain
- freqdomain_cpus is the list of CPUs (online+offline) that share
- the same clock/freq domain (possibly at the hardware level).
- That information may be hidden from the cpufreq core and the
- value of related_cpus may be different from freqdomain_cpus. This
- attribute is useful for user space DVFS controllers to get better
- power/performance results for platforms using acpi-cpufreq.
- This file is only present if the acpi-cpufreq or the cppc-cpufreq
- drivers are in use.
- What: /sys/devices/system/cpu/cpu*/cache/index3/cache_disable_{0,1}
- Date: August 2008
- KernelVersion: 2.6.27
- Contact: Linux kernel mailing list <[email protected]>
- Description: Disable L3 cache indices
- These files exist in every CPU's cache/index3 directory. Each
- cache_disable_{0,1} file corresponds to one disable slot which
- can be used to disable a cache index. Reading from these files
- on a processor with this functionality will return the currently
- disabled index for that node. There is one L3 structure per
- node, or per internal node on MCM machines. Writing a valid
- index to one of these files will cause the specified cache
- index to be disabled.
- All AMD processors with L3 caches provide this functionality.
- For details, see BKDGs at
- https://www.amd.com/en/support/tech-docs?keyword=bios+kernel
- What: /sys/devices/system/cpu/cpufreq/boost
- Date: August 2012
- Contact: Linux kernel mailing list <[email protected]>
- Description: Processor frequency boosting control
- This switch controls the boost setting for the whole system.
- Boosting allows the CPU and the firmware to run at a frequency
- beyond its nominal limit.
- More details can be found in
- Documentation/admin-guide/pm/cpufreq.rst
- What: /sys/devices/system/cpu/cpuX/crash_notes
- /sys/devices/system/cpu/cpuX/crash_notes_size
- Date: April 2013
- Contact: [email protected]
- Description: address and size of the percpu note.
- crash_notes: the physical address of the memory that holds the
- note of cpuX.
- crash_notes_size: size of the note of cpuX.
- What: /sys/devices/system/cpu/intel_pstate/max_perf_pct
- /sys/devices/system/cpu/intel_pstate/min_perf_pct
- /sys/devices/system/cpu/intel_pstate/no_turbo
- Date: February 2013
- Contact: [email protected]
- Description: Parameters for the Intel P-state driver
- Logic for selecting the current P-state in Intel
- Sandybridge+ processors. The three knobs control
- limits for the P-state that will be requested by the
- driver.
- max_perf_pct: limits the maximum P state that will be requested by
- the driver stated as a percentage of the available performance.
- min_perf_pct: limits the minimum P state that will be requested by
- the driver stated as a percentage of the available performance.
- no_turbo: limits the driver to selecting P states below the turbo
- frequency range.
- More details can be found in
- Documentation/admin-guide/pm/intel_pstate.rst
- What: /sys/devices/system/cpu/cpu*/cache/index*/<set_of_attributes_mentioned_below>
- Date: July 2014(documented, existed before August 2008)
- Contact: Sudeep Holla <[email protected]>
- Linux kernel mailing list <[email protected]>
- Description: Parameters for the CPU cache attributes
- allocation_policy:
- - WriteAllocate:
- allocate a memory location to a cache line
- on a cache miss because of a write
- - ReadAllocate:
- allocate a memory location to a cache line
- on a cache miss because of a read
- - ReadWriteAllocate:
- both writeallocate and readallocate
- attributes:
- LEGACY used only on IA64 and is same as write_policy
- coherency_line_size:
- the minimum amount of data in bytes that gets
- transferred from memory to cache
- level:
- the cache hierarchy in the multi-level cache configuration
- number_of_sets:
- total number of sets in the cache, a set is a
- collection of cache lines with the same cache index
- physical_line_partition:
- number of physical cache line per cache tag
- shared_cpu_list:
- the list of logical cpus sharing the cache
- shared_cpu_map:
- logical cpu mask containing the list of cpus sharing
- the cache
- size:
- the total cache size in kB
- type:
- - Instruction: cache that only holds instructions
- - Data: cache that only caches data
- - Unified: cache that holds both data and instructions
- ways_of_associativity:
- degree of freedom in placing a particular block
- of memory in the cache
- write_policy:
- - WriteThrough:
- data is written to both the cache line
- and to the block in the lower-level memory
- - WriteBack:
- data is written only to the cache line and
- the modified cache line is written to main
- memory only when it is replaced
- What: /sys/devices/system/cpu/cpu*/cache/index*/id
- Date: September 2016
- Contact: Linux kernel mailing list <[email protected]>
- Description: Cache id
- The id provides a unique number for a specific instance of
- a cache of a particular type. E.g. there may be a level
- 3 unified cache on each socket in a server and we may
- assign them ids 0, 1, 2, ...
- Note that id value can be non-contiguous. E.g. level 1
- caches typically exist per core, but there may not be a
- power of two cores on a socket, so these caches may be
- numbered 0, 1, 2, 3, 4, 5, 8, 9, 10, ...
- What: /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats
- /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/turbo_stat
- /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/sub_turbo_stat
- /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/unthrottle
- /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/powercap
- /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/overtemp
- /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/supply_fault
- /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/overcurrent
- /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats/occ_reset
- Date: March 2016
- Contact: Linux kernel mailing list <[email protected]>
- Linux for PowerPC mailing list <[email protected]>
- Description: POWERNV CPUFreq driver's frequency throttle stats directory and
- attributes
- 'cpuX/cpufreq/throttle_stats' directory contains the CPU frequency
- throttle stat attributes for the chip. The throttle stats of a cpu
- is common across all the cpus belonging to a chip. Below are the
- throttle attributes exported in the 'throttle_stats' directory:
- - turbo_stat : This file gives the total number of times the max
- frequency is throttled to lower frequency in turbo (at and above
- nominal frequency) range of frequencies.
- - sub_turbo_stat : This file gives the total number of times the
- max frequency is throttled to lower frequency in sub-turbo(below
- nominal frequency) range of frequencies.
- - unthrottle : This file gives the total number of times the max
- frequency is unthrottled after being throttled.
- - powercap : This file gives the total number of times the max
- frequency is throttled due to 'Power Capping'.
- - overtemp : This file gives the total number of times the max
- frequency is throttled due to 'CPU Over Temperature'.
- - supply_fault : This file gives the total number of times the
- max frequency is throttled due to 'Power Supply Failure'.
- - overcurrent : This file gives the total number of times the
- max frequency is throttled due to 'Overcurrent'.
- - occ_reset : This file gives the total number of times the max
- frequency is throttled due to 'OCC Reset'.
- The sysfs attributes representing different throttle reasons like
- powercap, overtemp, supply_fault, overcurrent and occ_reset map to
- the reasons provided by OCC firmware for throttling the frequency.
- What: /sys/devices/system/cpu/cpufreq/policyX/throttle_stats
- /sys/devices/system/cpu/cpufreq/policyX/throttle_stats/turbo_stat
- /sys/devices/system/cpu/cpufreq/policyX/throttle_stats/sub_turbo_stat
- /sys/devices/system/cpu/cpufreq/policyX/throttle_stats/unthrottle
- /sys/devices/system/cpu/cpufreq/policyX/throttle_stats/powercap
- /sys/devices/system/cpu/cpufreq/policyX/throttle_stats/overtemp
- /sys/devices/system/cpu/cpufreq/policyX/throttle_stats/supply_fault
- /sys/devices/system/cpu/cpufreq/policyX/throttle_stats/overcurrent
- /sys/devices/system/cpu/cpufreq/policyX/throttle_stats/occ_reset
- Date: March 2016
- Contact: Linux kernel mailing list <[email protected]>
- Linux for PowerPC mailing list <[email protected]>
- Description: POWERNV CPUFreq driver's frequency throttle stats directory and
- attributes
- 'policyX/throttle_stats' directory and all the attributes are same as
- the /sys/devices/system/cpu/cpuX/cpufreq/throttle_stats directory and
- attributes which give the frequency throttle information of the chip.
- What: /sys/devices/system/cpu/cpuX/regs/
- /sys/devices/system/cpu/cpuX/regs/identification/
- /sys/devices/system/cpu/cpuX/regs/identification/midr_el1
- /sys/devices/system/cpu/cpuX/regs/identification/revidr_el1
- /sys/devices/system/cpu/cpuX/regs/identification/smidr_el1
- Date: June 2016
- Contact: Linux ARM Kernel Mailing list <[email protected]>
- Description: AArch64 CPU registers
- 'identification' directory exposes the CPU ID registers for
- identifying model and revision of the CPU and SMCU.
- What: /sys/devices/system/cpu/aarch32_el0
- Date: May 2021
- Contact: Linux ARM Kernel Mailing list <[email protected]>
- Description: Identifies the subset of CPUs in the system that can execute
- AArch32 (32-bit ARM) applications. If present, the same format as
- /sys/devices/system/cpu/{offline,online,possible,present} is used.
- If absent, then all or none of the CPUs can execute AArch32
- applications and execve() will behave accordingly.
- What: /sys/devices/system/cpu/cpuX/cpu_capacity
- Date: December 2016
- Contact: Linux kernel mailing list <[email protected]>
- Description: information about CPUs heterogeneity.
- cpu_capacity: capacity of cpuX.
- What: /sys/devices/system/cpu/vulnerabilities
- /sys/devices/system/cpu/vulnerabilities/gather_data_sampling
- /sys/devices/system/cpu/vulnerabilities/itlb_multihit
- /sys/devices/system/cpu/vulnerabilities/l1tf
- /sys/devices/system/cpu/vulnerabilities/mds
- /sys/devices/system/cpu/vulnerabilities/meltdown
- /sys/devices/system/cpu/vulnerabilities/mmio_stale_data
- /sys/devices/system/cpu/vulnerabilities/retbleed
- /sys/devices/system/cpu/vulnerabilities/spec_store_bypass
- /sys/devices/system/cpu/vulnerabilities/spectre_v1
- /sys/devices/system/cpu/vulnerabilities/spectre_v2
- /sys/devices/system/cpu/vulnerabilities/srbds
- /sys/devices/system/cpu/vulnerabilities/tsx_async_abort
- Date: January 2018
- Contact: Linux kernel mailing list <[email protected]>
- Description: Information about CPU vulnerabilities
- The files are named after the code names of CPU
- vulnerabilities. The output of those files reflects the
- state of the CPUs in the system. Possible output values:
- ================ ==============================================
- "Not affected" CPU is not affected by the vulnerability
- "Vulnerable" CPU is affected and no mitigation in effect
- "Mitigation: $M" CPU is affected and mitigation $M is in effect
- ================ ==============================================
- See also: Documentation/admin-guide/hw-vuln/index.rst
- What: /sys/devices/system/cpu/smt
- /sys/devices/system/cpu/smt/active
- /sys/devices/system/cpu/smt/control
- Date: June 2018
- Contact: Linux kernel mailing list <[email protected]>
- Description: Control Symmetric Multi Threading (SMT)
- active: Tells whether SMT is active (enabled and siblings online)
- control: Read/write interface to control SMT. Possible
- values:
- ================ =========================================
- "on" SMT is enabled
- "off" SMT is disabled
- "forceoff" SMT is force disabled. Cannot be changed.
- "notsupported" SMT is not supported by the CPU
- "notimplemented" SMT runtime toggling is not
- implemented for the architecture
- ================ =========================================
- If control status is "forceoff" or "notsupported" writes
- are rejected.
- What: /sys/devices/system/cpu/cpuX/power/energy_perf_bias
- Date: March 2019
- Contact: [email protected]
- Description: Intel Energy and Performance Bias Hint (EPB)
- 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.
- 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.
- 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
- 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.
- 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.
- 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
- "asymm" Prefer asymmetric mode
- "async" Prefer asynchronous mode
- ================ ==============================================
- See also: Documentation/arm64/memory-tagging-extension.rst
- What: /sys/devices/system/cpu/nohz_full
- Date: Apr 2015
- Contact: Linux kernel mailing list <[email protected]>
- Description:
- (RO) the list of CPUs that are in nohz_full mode.
- These CPUs are set by boot parameter "nohz_full=".
- What: /sys/devices/system/cpu/isolated
- Date: Apr 2015
- Contact: Linux kernel mailing list <[email protected]>
- Description:
- (RO) the list of CPUs that are isolated and don't
- participate in load balancing. These CPUs are set by
- boot parameter "isolcpus=".
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