\ sphinx.addnodesdocument)}( rawsource children]( translations
LanguagesNode)}(hhh](h pending_xref)}(hhh]docutils.nodesTextChinese (Simplified)}parenthsba
attributes}(ids]classes]names]dupnames]backrefs] refdomainstdreftypedoc reftargetA/translations/zh_CN/admin-guide/pm/intel_uncore_frequency_scalingmodnameN classnameN refexplicitutagnamehhh ubh)}(hhh]hChinese (Traditional)}hh2sbah }(h ]h ]h"]h$]h&] refdomainh)reftypeh+ reftargetA/translations/zh_TW/admin-guide/pm/intel_uncore_frequency_scalingmodnameN classnameN refexplicituh1hhh ubh)}(hhh]hItalian}hhFsbah }(h ]h ]h"]h$]h&] refdomainh)reftypeh+ reftargetA/translations/it_IT/admin-guide/pm/intel_uncore_frequency_scalingmodnameN classnameN refexplicituh1hhh ubh)}(hhh]hJapanese}hhZsbah }(h ]h ]h"]h$]h&] refdomainh)reftypeh+ reftargetA/translations/ja_JP/admin-guide/pm/intel_uncore_frequency_scalingmodnameN classnameN refexplicituh1hhh ubh)}(hhh]hKorean}hhnsbah }(h ]h ]h"]h$]h&] refdomainh)reftypeh+ reftargetA/translations/ko_KR/admin-guide/pm/intel_uncore_frequency_scalingmodnameN classnameN refexplicituh1hhh ubh)}(hhh]hPortuguese (Brazilian)}hhsbah }(h ]h ]h"]h$]h&] refdomainh)reftypeh+ reftargetA/translations/pt_BR/admin-guide/pm/intel_uncore_frequency_scalingmodnameN classnameN refexplicituh1hhh ubh)}(hhh]hSpanish}hhsbah }(h ]h ]h"]h$]h&] refdomainh)reftypeh+ reftargetA/translations/sp_SP/admin-guide/pm/intel_uncore_frequency_scalingmodnameN classnameN refexplicituh1hhh ubeh }(h ]h ]h"]h$]h&]current_languageEnglishuh1h
hh _documenthsourceNlineNubhcomment)}(h SPDX-License-Identifier: GPL-2.0h]h SPDX-License-Identifier: GPL-2.0}hhsbah }(h ]h ]h"]h$]h&] xml:spacepreserveuh1hhhhhh[/var/lib/git/docbuild/linux/Documentation/admin-guide/pm/intel_uncore_frequency_scaling.rsthKubh)}(h4This data file has been placed in the public domain.h]h4This data file has been placed in the public domain.}hhsbah }(h ]h ]h"]h$]h&]hhuh1hhhhhho/srv/docbuild/lib/venvs/build-kernel-docs/lib64/python3.9/site-packages/docutils/parsers/rst/include/isonum.txthKubh)}(hDerived from the Unicode character mappings available from
.
Processed by unicode2rstsubs.py, part of Docutils:
.h]hDerived from the Unicode character mappings available from
.
Processed by unicode2rstsubs.py, part of Docutils:
.}hhsbah }(h ]h ]h"]h$]h&]hhuh1hhhhhhhhKubhsubstitution_definition)}(h*.. |amp| unicode:: U+00026 .. AMPERSANDh]h&}hhsbah }(h ]h ]h"]ampah$]h&]uh1hhhhKhhhhubh)}(h+.. |apos| unicode:: U+00027 .. APOSTROPHEh]h'}hhsbah }(h ]h ]h"]aposah$]h&]uh1hhhhKhhhhubh)}(h).. |ast| unicode:: U+0002A .. ASTERISKh]h*}hj sbah }(h ]h ]h"]astah$]h&]uh1hhhhK hhhhubh)}(h+.. |brvbar| unicode:: U+000A6 .. BROKEN BARh]h¦}hj sbah }(h ]h ]h"]brvbarah$]h&]uh1hhhhK
hhhhubh)}(h0.. |bsol| unicode:: U+0005C .. REVERSE SOLIDUSh]h\}hj# sbah }(h ]h ]h"]bsolah$]h&]uh1hhhhK hhhhubh)}(h*.. |cent| unicode:: U+000A2 .. CENT SIGNh]h¢}hj2 sbah }(h ]h ]h"]centah$]h&]uh1hhhhK hhhhubh)}(h&.. |colon| unicode:: U+0003A .. COLONh]h:}hjA sbah }(h ]h ]h"]colonah$]h&]uh1hhhhK
hhhhubh)}(h&.. |comma| unicode:: U+0002C .. COMMAh]h,}hjP sbah }(h ]h ]h"]commaah$]h&]uh1hhhhKhhhhubh)}(h... |commat| unicode:: U+00040 .. COMMERCIAL ATh]h@}hj_ sbah }(h ]h ]h"]commatah$]h&]uh1hhhhKhhhhubh)}(h/.. |copy| unicode:: U+000A9 .. COPYRIGHT SIGNh]h©}hjn sbah }(h ]h ]h"]copyah$]h&]uh1hhhhKhhhhubh)}(h... |curren| unicode:: U+000A4 .. CURRENCY SIGNh]h¤}hj} sbah }(h ]h ]h"]currenah$]h&]uh1hhhhKhhhhubh)}(h0.. |darr| unicode:: U+02193 .. DOWNWARDS ARROWh]h↓}hj sbah }(h ]h ]h"]darrah$]h&]uh1hhhhKhhhhubh)}(h,.. |deg| unicode:: U+000B0 .. DEGREE SIGNh]h°}hj sbah }(h ]h ]h"]degah$]h&]uh1hhhhKhhhhubh)}(h... |divide| unicode:: U+000F7 .. DIVISION SIGNh]h÷}hj sbah }(h ]h ]h"]divideah$]h&]uh1hhhhKhhhhubh)}(h,.. |dollar| unicode:: U+00024 .. DOLLAR SIGNh]h$}hj sbah }(h ]h ]h"]dollarah$]h&]uh1hhhhKhhhhubh)}(h,.. |equals| unicode:: U+0003D .. EQUALS SIGNh]h=}hj sbah }(h ]h ]h"]equalsah$]h&]uh1hhhhKhhhhubh)}(h1.. |excl| unicode:: U+00021 .. EXCLAMATION MARKh]h!}hj sbah }(h ]h ]h"]exclah$]h&]uh1hhhhKhhhhubh)}(h9.. |frac12| unicode:: U+000BD .. VULGAR FRACTION ONE HALFh]h½}hj sbah }(h ]h ]h"]frac12ah$]h&]uh1hhhhKhhhhubh)}(h<.. |frac14| unicode:: U+000BC .. VULGAR FRACTION ONE QUARTERh]h¼}hj sbah }(h ]h ]h"]frac14ah$]h&]uh1hhhhKhhhhubh)}(h;.. |frac18| unicode:: U+0215B .. VULGAR FRACTION ONE EIGHTHh]h⅛}hj sbah }(h ]h ]h"]frac18ah$]h&]uh1hhhhKhhhhubh)}(h?.. |frac34| unicode:: U+000BE .. VULGAR FRACTION THREE QUARTERSh]h¾}hj sbah }(h ]h ]h"]frac34ah$]h&]uh1hhhhKhhhhubh)}(h>.. |frac38| unicode:: U+0215C .. VULGAR FRACTION THREE EIGHTHSh]h⅜}hj" sbah }(h ]h ]h"]frac38ah$]h&]uh1hhhhK hhhhubh)}(h=.. |frac58| unicode:: U+0215D .. VULGAR FRACTION FIVE EIGHTHSh]h⅝}hj1 sbah }(h ]h ]h"]frac58ah$]h&]uh1hhhhK hhhhubh)}(h>.. |frac78| unicode:: U+0215E .. VULGAR FRACTION SEVEN EIGHTHSh]h⅞}hj@ sbah }(h ]h ]h"]frac78ah$]h&]uh1hhhhK hhhhubh)}(h2.. |gt| unicode:: U+0003E .. GREATER-THAN SIGNh]h>}hjO sbah }(h ]h ]h"]gtah$]h&]uh1hhhhK hhhhubh)}(h9.. |half| unicode:: U+000BD .. VULGAR FRACTION ONE HALFh]h½}hj^ sbah }(h ]h ]h"]halfah$]h&]uh1hhhhK hhhhubh)}(h/.. |horbar| unicode:: U+02015 .. HORIZONTAL BARh]h―}hjm sbah }(h ]h ]h"]horbarah$]h&]uh1hhhhK!hhhhubh)}(h'.. |hyphen| unicode:: U+02010 .. HYPHENh]h‐}hj| sbah }(h ]h ]h"]hyphenah$]h&]uh1hhhhK"hhhhubh)}(h:.. |iexcl| unicode:: U+000A1 .. INVERTED EXCLAMATION MARKh]h¡}hj sbah }(h ]h ]h"]iexclah$]h&]uh1hhhhK#hhhhubh)}(h7.. |iquest| unicode:: U+000BF .. INVERTED QUESTION MARKh]h¿}hj sbah }(h ]h ]h"]iquestah$]h&]uh1hhhhK$hhhhubh)}(hJ.. |laquo| unicode:: U+000AB .. LEFT-POINTING DOUBLE ANGLE QUOTATION MARKh]h«}hj sbah }(h ]h ]h"]laquoah$]h&]uh1hhhhK%hhhhubh)}(h0.. |larr| unicode:: U+02190 .. LEFTWARDS ARROWh]h←}hj sbah }(h ]h ]h"]larrah$]h&]uh1hhhhK&hhhhubh)}(h3.. |lcub| unicode:: U+0007B .. LEFT CURLY BRACKETh]h{}hj sbah }(h ]h ]h"]lcubah$]h&]uh1hhhhK'hhhhubh)}(h;.. |ldquo| unicode:: U+0201C .. LEFT DOUBLE QUOTATION MARKh]h“}hj sbah }(h ]h ]h"]ldquoah$]h&]uh1hhhhK(hhhhubh)}(h).. |lowbar| unicode:: U+0005F .. LOW LINEh]h_}hj sbah }(h ]h ]h"]lowbarah$]h&]uh1hhhhK)hhhhubh)}(h1.. |lpar| unicode:: U+00028 .. LEFT PARENTHESISh]h(}hj sbah }(h ]h ]h"]lparah$]h&]uh1hhhhK*hhhhubh)}(h4.. |lsqb| unicode:: U+0005B .. LEFT SQUARE BRACKETh]h[}hj sbah }(h ]h ]h"]lsqbah$]h&]uh1hhhhK+hhhhubh)}(h;.. |lsquo| unicode:: U+02018 .. LEFT SINGLE QUOTATION MARKh]h‘}hj sbah }(h ]h ]h"]lsquoah$]h&]uh1hhhhK,hhhhubh)}(h/.. |lt| unicode:: U+0003C .. LESS-THAN SIGNh]h<}hj! sbah }(h ]h ]h"]ltah$]h&]uh1hhhhK-hhhhubh)}(h+.. |micro| unicode:: U+000B5 .. MICRO SIGNh]hµ}hj0 sbah }(h ]h ]h"]microah$]h&]uh1hhhhK.hhhhubh)}(h+.. |middot| unicode:: U+000B7 .. MIDDLE DOTh]h·}hj? sbah }(h ]h ]h"]middotah$]h&]uh1hhhhK/hhhhubh)}(h/.. |nbsp| unicode:: U+000A0 .. NO-BREAK SPACEh]h }hjN sbah }(h ]h ]h"]nbspah$]h&]uh1hhhhK0hhhhubh)}(h).. |not| unicode:: U+000AC .. NOT SIGNh]h¬}hj] sbah }(h ]h ]h"]notah$]h&]uh1hhhhK1hhhhubh)}(h,.. |num| unicode:: U+00023 .. NUMBER SIGNh]h#}hjl sbah }(h ]h ]h"]numah$]h&]uh1hhhhK2hhhhubh)}(h).. |ohm| unicode:: U+02126 .. OHM SIGNh]hΩ}hj{ sbah }(h ]h ]h"]ohmah$]h&]uh1hhhhK3hhhhubh)}(h;.. |ordf| unicode:: U+000AA .. FEMININE ORDINAL INDICATORh]hª}hj sbah }(h ]h ]h"]ordfah$]h&]uh1hhhhK4hhhhubh)}(h<.. |ordm| unicode:: U+000BA .. MASCULINE ORDINAL INDICATORh]hº}hj sbah }(h ]h ]h"]ordmah$]h&]uh1hhhhK5hhhhubh)}(h-.. |para| unicode:: U+000B6 .. PILCROW SIGNh]h¶}hj sbah }(h ]h ]h"]paraah$]h&]uh1hhhhK6hhhhubh)}(h-.. |percnt| unicode:: U+00025 .. PERCENT SIGNh]h%}hj sbah }(h ]h ]h"]percntah$]h&]uh1hhhhK7hhhhubh)}(h*.. |period| unicode:: U+0002E .. FULL STOPh]h.}hj sbah }(h ]h ]h"]periodah$]h&]uh1hhhhK8hhhhubh)}(h*.. |plus| unicode:: U+0002B .. PLUS SIGNh]h+}hj sbah }(h ]h ]h"]plusah$]h&]uh1hhhhK9hhhhubh)}(h0.. |plusmn| unicode:: U+000B1 .. PLUS-MINUS SIGNh]h±}hj sbah }(h ]h ]h"]plusmnah$]h&]uh1hhhhK:hhhhubh)}(h+.. |pound| unicode:: U+000A3 .. POUND SIGNh]h£}hj sbah }(h ]h ]h"]poundah$]h&]uh1hhhhK;hhhhubh)}(h... |quest| unicode:: U+0003F .. QUESTION MARKh]h?}hj sbah }(h ]h ]h"]questah$]h&]uh1hhhhKhhhhubh)}(h1.. |rarr| unicode:: U+02192 .. RIGHTWARDS ARROWh]h→}hj/ sbah }(h ]h ]h"]rarrah$]h&]uh1hhhhK?hhhhubh)}(h4.. |rcub| unicode:: U+0007D .. RIGHT CURLY BRACKETh]h}}hj> sbah }(h ]h ]h"]rcubah$]h&]uh1hhhhK@hhhhubh)}(h<.. |rdquo| unicode:: U+0201D .. RIGHT DOUBLE QUOTATION MARKh]h”}hjM sbah }(h ]h ]h"]rdquoah$]h&]uh1hhhhKAhhhhubh)}(h0.. |reg| unicode:: U+000AE .. REGISTERED SIGNh]h®}hj\ sbah }(h ]h ]h"]regah$]h&]uh1hhhhKBhhhhubh)}(h2.. |rpar| unicode:: U+00029 .. RIGHT PARENTHESISh]h)}hjk sbah }(h ]h ]h"]rparah$]h&]uh1hhhhKChhhhubh)}(h5.. |rsqb| unicode:: U+0005D .. RIGHT SQUARE BRACKETh]h]}hjz sbah }(h ]h ]h"]rsqbah$]h&]uh1hhhhKDhhhhubh)}(h<.. |rsquo| unicode:: U+02019 .. RIGHT SINGLE QUOTATION MARKh]h’}hj sbah }(h ]h ]h"]rsquoah$]h&]uh1hhhhKEhhhhubh)}(h-.. |sect| unicode:: U+000A7 .. SECTION SIGNh]h§}hj sbah }(h ]h ]h"]sectah$]h&]uh1hhhhKFhhhhubh)}(h*.. |semi| unicode:: U+0003B .. SEMICOLONh]h;}hj sbah }(h ]h ]h"]semiah$]h&]uh1hhhhKGhhhhubh)}(h,.. |shy| unicode:: U+000AD .. SOFT HYPHENh]h}hj sbah }(h ]h ]h"]shyah$]h&]uh1hhhhKHhhhhubh)}(h(.. |sol| unicode:: U+0002F .. SOLIDUSh]h/}hj sbah }(h ]h ]h"]solah$]h&]uh1hhhhKIhhhhubh)}(h,.. |sung| unicode:: U+0266A .. EIGHTH NOTEh]h♪}hj sbah }(h ]h ]h"]sungah$]h&]uh1hhhhKJhhhhubh)}(h0.. |sup1| unicode:: U+000B9 .. SUPERSCRIPT ONEh]h¹}hj sbah }(h ]h ]h"]sup1ah$]h&]uh1hhhhKKhhhhubh)}(h0.. |sup2| unicode:: U+000B2 .. SUPERSCRIPT TWOh]h²}hj sbah }(h ]h ]h"]sup2ah$]h&]uh1hhhhKLhhhhubh)}(h2.. |sup3| unicode:: U+000B3 .. SUPERSCRIPT THREEh]h³}hj sbah }(h ]h ]h"]sup3ah$]h&]uh1hhhhKMhhhhubh)}(h4.. |times| unicode:: U+000D7 .. MULTIPLICATION SIGNh]h×}hj sbah }(h ]h ]h"]timesah$]h&]uh1hhhhKNhhhhubh)}(h0.. |trade| unicode:: U+02122 .. TRADE MARK SIGNh]h™}hj sbah }(h ]h ]h"]tradeah$]h&]uh1hhhhKOhhhhubh)}(h... |uarr| unicode:: U+02191 .. UPWARDS ARROWh]h↑}hj. sbah }(h ]h ]h"]uarrah$]h&]uh1hhhhKPhhhhubh)}(h... |verbar| unicode:: U+0007C .. VERTICAL LINEh]h|}hj= sbah }(h ]h ]h"]verbarah$]h&]uh1hhhhKQhhhhubh)}(h*.. |yen| unicode:: U+000A5 .. YEN SIGN
h]h¥}hjL sbah }(h ]h ]h"]yenah$]h&]uh1hhhhKRhhhhubhsection)}(hhh](htitle)}(h Intel Uncore Frequency Scalingh]h Intel Uncore Frequency Scaling}(hjb hhhNhNubah }(h ]h ]h"]h$]h&]uh1j` hj] hhhhhKubh
field_list)}(hhh](hfield)}(hhh](h
field_name)}(h Copyrighth]h Copyright}(hj| hhhNhNubah }(h ]h ]h"]h$]h&]uh1jz hjw hhhK ubh
field_body)}(h#|copy| 2022-2023 Intel Corporation
h]h paragraph)}(h"|copy| 2022-2023 Intel Corporationh](h©}(hj hhhNhNubh 2022-2023 Intel Corporation}(hj hhhNhNubeh }(h ]h ]h"]h$]h&]uh1j hhhKhj ubah }(h ]h ]h"]h$]h&]uh1j hjw ubeh }(h ]h ]h"]h$]h&]uh1ju hhhKhjr hhubjv )}(hhh](j{ )}(hAuthorh]hAuthor}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1jz hj hhhK ubj )}(h:Srinivas Pandruvada
h]j )}(h9Srinivas Pandruvada h](hSrinivas Pandruvada <}(hj hhhNhNubh reference)}(h#srinivas.pandruvada@linux.intel.comh]h#srinivas.pandruvada@linux.intel.com}(hj hhhNhNubah }(h ]h ]h"]h$]h&]refuri*mailto:srinivas.pandruvada@linux.intel.comuh1j hj ubh>}(hj hhhNhNubeh }(h ]h ]h"]h$]h&]uh1j hhhK
hj ubah }(h ]h ]h"]h$]h&]uh1j hj ubeh }(h ]h ]h"]h$]h&]uh1ju hhhK
hjr hhubeh }(h ]h ]h"]h$]h&]uh1jp hj] hhhhhKubj\ )}(hhh](ja )}(h Introductionh]h Introduction}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j` hj hhhhhK
ubj )}(hX; The uncore can consume significant amount of power in Intel's Xeon servers based
on the workload characteristics. To optimize the total power and improve overall
performance, SoCs have internal algorithms for scaling uncore frequency. These
algorithms monitor workload usage of uncore and set a desirable frequency.h]hX= The uncore can consume significant amount of power in Intel’s Xeon servers based
on the workload characteristics. To optimize the total power and improve overall
performance, SoCs have internal algorithms for scaling uncore frequency. These
algorithms monitor workload usage of uncore and set a desirable frequency.}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj hhubj )}(hX6 It is possible that users have different expectations of uncore performance and
want to have control over it. The objective is similar to allowing users to set
the scaling min/max frequencies via cpufreq sysfs to improve CPU performance.
Users may have some latency sensitive workloads where they do not want any
change to uncore frequency. Also, users may have workloads which require
different core and uncore performance at distinct phases and they may want to
use both cpufreq and the uncore scaling interface to distribute power and
improve overall performance.h]hX6 It is possible that users have different expectations of uncore performance and
want to have control over it. The objective is similar to allowing users to set
the scaling min/max frequencies via cpufreq sysfs to improve CPU performance.
Users may have some latency sensitive workloads where they do not want any
change to uncore frequency. Also, users may have workloads which require
different core and uncore performance at distinct phases and they may want to
use both cpufreq and the uncore scaling interface to distribute power and
improve overall performance.}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj hhubeh }(h ] introductionah ]h"] introductionah$]h&]uh1j[ hj] hhhhhK
ubj\ )}(hhh](ja )}(hSysfs Interfaceh]hSysfs Interface}(hj3 hhhNhNubah }(h ]h ]h"]h$]h&]uh1j` hj0 hhhhhK ubj )}(hTo control uncore frequency, a sysfs interface is provided in the directory:
`/sys/devices/system/cpu/intel_uncore_frequency/`.h](hMTo control uncore frequency, a sysfs interface is provided in the directory:
}(hjA hhhNhNubhtitle_reference)}(h1`/sys/devices/system/cpu/intel_uncore_frequency/`h]h//sys/devices/system/cpu/intel_uncore_frequency/}(hjK hhhNhNubah }(h ]h ]h"]h$]h&]uh1jI hjA ubh.}(hjA hhhNhNubeh }(h ]h ]h"]h$]h&]uh1j hhhK hj0 hhubj )}(hX$ There is one directory for each package and die combination as the scope of
uncore scaling control is per die in multiple die/package SoCs or per
package for single die per package SoCs. The name represents the
scope of control. For example: 'package_00_die_00' is for package id 0 and
die 0.h]hX( There is one directory for each package and die combination as the scope of
uncore scaling control is per die in multiple die/package SoCs or per
package for single die per package SoCs. The name represents the
scope of control. For example: ‘package_00_die_00’ is for package id 0 and
die 0.}(hjc hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhK#hj0 hhubj )}(h7Each package_*_die_* contains the following attributes:h]h7Each package_*_die_* contains the following attributes:}(hjq hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhK)hj0 hhubhdefinition_list)}(hhh](hdefinition_list_item)}(h``initial_max_freq_khz``
Out of reset, this attribute represent the maximum possible frequency.
This is a read-only attribute. If users adjust max_freq_khz,
they can always go back to maximum using the value from this attribute.
h](hterm)}(h``initial_max_freq_khz``h]hliteral)}(hj h]hinitial_max_freq_khz}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hj ubah }(h ]h ]h"]h$]h&]uh1j hhhK.hj ubh
definition)}(hhh]j )}(hOut of reset, this attribute represent the maximum possible frequency.
This is a read-only attribute. If users adjust max_freq_khz,
they can always go back to maximum using the value from this attribute.h]hOut of reset, this attribute represent the maximum possible frequency.
This is a read-only attribute. If users adjust max_freq_khz,
they can always go back to maximum using the value from this attribute.}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhK,hj ubah }(h ]h ]h"]h$]h&]uh1j hj ubeh }(h ]h ]h"]h$]h&]uh1j hhhK.hj ubj )}(h``initial_min_freq_khz``
Out of reset, this attribute represent the minimum possible frequency.
This is a read-only attribute. If users adjust min_freq_khz,
they can always go back to minimum using the value from this attribute.
h](j )}(h``initial_min_freq_khz``h]j )}(hj h]hinitial_min_freq_khz}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hj ubah }(h ]h ]h"]h$]h&]uh1j hhhK3hj ubj )}(hhh]j )}(hOut of reset, this attribute represent the minimum possible frequency.
This is a read-only attribute. If users adjust min_freq_khz,
they can always go back to minimum using the value from this attribute.h]hOut of reset, this attribute represent the minimum possible frequency.
This is a read-only attribute. If users adjust min_freq_khz,
they can always go back to minimum using the value from this attribute.}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhK1hj ubah }(h ]h ]h"]h$]h&]uh1j hj ubeh }(h ]h ]h"]h$]h&]uh1j hhhK3hj hhubj )}(hM``max_freq_khz``
This attribute is used to set the maximum uncore frequency.
h](j )}(h``max_freq_khz``h]j )}(hj h]h max_freq_khz}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hj ubah }(h ]h ]h"]h$]h&]uh1j hhhK6hj ubj )}(hhh]j )}(h;This attribute is used to set the maximum uncore frequency.h]h;This attribute is used to set the maximum uncore frequency.}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhK6hj ubah }(h ]h ]h"]h$]h&]uh1j hj ubeh }(h ]h ]h"]h$]h&]uh1j hhhK6hj hhubj )}(hM``min_freq_khz``
This attribute is used to set the minimum uncore frequency.
h](j )}(h``min_freq_khz``h]j )}(hj: h]h min_freq_khz}(hj< hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hj8 ubah }(h ]h ]h"]h$]h&]uh1j hhhK9hj4 ubj )}(hhh]j )}(h;This attribute is used to set the minimum uncore frequency.h]h;This attribute is used to set the minimum uncore frequency.}(hjR hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhK9hjO ubah }(h ]h ]h"]h$]h&]uh1j hj4 ubeh }(h ]h ]h"]h$]h&]uh1j hhhK9hj hhubj )}(hQ``current_freq_khz``
This attribute is used to get the current uncore frequency.
h](j )}(h``current_freq_khz``h]j )}(hjr h]hcurrent_freq_khz}(hjt hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hjp ubah }(h ]h ]h"]h$]h&]uh1j hhhKThis attribute is used to get the package id of this instance.h]h>This attribute is used to get the package id of this instance.}(hj& hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKnhj# ubah }(h ]h ]h"]h$]h&]uh1j hj ubeh }(h ]h ]h"]h$]h&]uh1j hhhKnhj% hhubj )}(h``agent_types``
This attribute displays all the hardware agents present within the
domain. Each agent has the capability to control one or more hardware
subsystems, which include: core, cache, memory, and I/O.
h](j )}(h``agent_types``h]j )}(hjF h]h agent_types}(hjH hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hjD ubah }(h ]h ]h"]h$]h&]uh1j hhhKshj@ ubj )}(hhh]j )}(hThis attribute displays all the hardware agents present within the
domain. Each agent has the capability to control one or more hardware
subsystems, which include: core, cache, memory, and I/O.h]hThis attribute displays all the hardware agents present within the
domain. Each agent has the capability to control one or more hardware
subsystems, which include: core, cache, memory, and I/O.}(hj^ hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKqhj[ ubah }(h ]h ]h"]h$]h&]uh1j hj@ ubeh }(h ]h ]h"]h$]h&]uh1j hhhKshj% hhubeh }(h ]h ]h"]h$]h&]uh1j hj hhhhhNubj )}(hDThe other attributes are same as presented at package_*_die_* level.h]hDThe other attributes are same as presented at package_*_die_* level.}(hj~ hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKuhj hhubj )}(hIn most of current use cases, the "max_freq_khz" and "min_freq_khz"
is updated at "package_*_die_*" level. This model will be still supported
with the following approach:h]hIn most of current use cases, the “max_freq_khz” and “min_freq_khz”
is updated at “package_*_die_*” level. This model will be still supported
with the following approach:}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKwhj hhubj )}(hX When user uses controls at "package_*_die_*" level, then every fabric
cluster is affected in that package and die. For example: user changes
"max_freq_khz" in the package_00_die_00, then "max_freq_khz" for uncore*
directory with the same package id will be updated. In this case user can
still update "max_freq_khz" at each uncore* level, which is more restrictive.
Similarly, user can update "min_freq_khz" at "package_*_die_*" level
to apply at each uncore* level.h]hX When user uses controls at “package_*_die_*” level, then every fabric
cluster is affected in that package and die. For example: user changes
“max_freq_khz” in the package_00_die_00, then “max_freq_khz” for uncore*
directory with the same package id will be updated. In this case user can
still update “max_freq_khz” at each uncore* level, which is more restrictive.
Similarly, user can update “min_freq_khz” at “package_*_die_*” level
to apply at each uncore* level.}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhK{hj hhubj )}(hkSupport for "current_freq_khz" is available only at each fabric cluster
level (i.e., in uncore* directory).h]hoSupport for “current_freq_khz” is available only at each fabric cluster
level (i.e., in uncore* directory).}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj hhubeh }(h ]?socs-with-tpmi-topology-aware-register-and-pm-capsule-interfaceah ]h"]Asocs with tpmi (topology aware register and pm capsule interface)ah$]h&]uh1j[ hj] hhhhhK?ubj\ )}(hhh](ja )}(h Efficiency vs. Latency Tradeoffh]h Efficiency vs. Latency Tradeoff}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j` hj hhhhhKubj )}(hX The Efficiency Latency Control (ELC) feature improves performance
per watt. With this feature hardware power management algorithms
optimize trade-off between latency and power consumption. For some
latency sensitive workloads further tuning can be done by SW to
get desired performance.h]hX The Efficiency Latency Control (ELC) feature improves performance
per watt. With this feature hardware power management algorithms
optimize trade-off between latency and power consumption. For some
latency sensitive workloads further tuning can be done by SW to
get desired performance.}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj hhubj )}(hX The hardware monitors the average CPU utilization across all cores
in a power domain at regular intervals and decides an uncore frequency.
While this may result in the best performance per watt, workload may be
expecting higher performance at the expense of power. Consider an
application that intermittently wakes up to perform memory reads on an
otherwise idle system. In such cases, if hardware lowers uncore
frequency, then there may be delay in ramp up of frequency to meet
target performance.h]hX The hardware monitors the average CPU utilization across all cores
in a power domain at regular intervals and decides an uncore frequency.
While this may result in the best performance per watt, workload may be
expecting higher performance at the expense of power. Consider an
application that intermittently wakes up to perform memory reads on an
otherwise idle system. In such cases, if hardware lowers uncore
frequency, then there may be delay in ramp up of frequency to meet
target performance.}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj hhubj )}(hX5 The ELC control defines some parameters which can be changed from SW.
If the average CPU utilization is below a user-defined threshold
(elc_low_threshold_percent attribute below), the user-defined uncore
floor frequency will be used (elc_floor_freq_khz attribute below)
instead of hardware calculated minimum.h]hX5 The ELC control defines some parameters which can be changed from SW.
If the average CPU utilization is below a user-defined threshold
(elc_low_threshold_percent attribute below), the user-defined uncore
floor frequency will be used (elc_floor_freq_khz attribute below)
instead of hardware calculated minimum.}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj hhubj )}(hX: Similarly in high load scenario where the CPU utilization goes above
the high threshold value (elc_high_threshold_percent attribute below)
instead of jumping to maximum uncore frequency, frequency is increased
in 100MHz steps. This avoids consuming unnecessarily high power
immediately with CPU utilization spikes.h]hX: Similarly in high load scenario where the CPU utilization goes above
the high threshold value (elc_high_threshold_percent attribute below)
instead of jumping to maximum uncore frequency, frequency is increased
in 100MHz steps. This avoids consuming unnecessarily high power
immediately with CPU utilization spikes.}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj hhubj )}(h*Attributes for efficiency latency control:h]h*Attributes for efficiency latency control:}(hj
hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj hhubj )}(hhh](j )}(h``elc_floor_freq_khz``
This attribute is used to get/set the efficiency latency floor frequency.
If this variable is lower than the 'min_freq_khz', it is ignored by
the firmware.
h](j )}(h``elc_floor_freq_khz``h]j )}(hj
h]helc_floor_freq_khz}(hj
hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hj
ubah }(h ]h ]h"]h$]h&]uh1j hhhKhj
ubj )}(hhh]j )}(hThis attribute is used to get/set the efficiency latency floor frequency.
If this variable is lower than the 'min_freq_khz', it is ignored by
the firmware.h]hThis attribute is used to get/set the efficiency latency floor frequency.
If this variable is lower than the ‘min_freq_khz’, it is ignored by
the firmware.}(hj6
hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj3
ubah }(h ]h ]h"]h$]h&]uh1j hj
ubeh }(h ]h ]h"]h$]h&]uh1j hhhKhj
ubj )}(h``elc_low_threshold_percent``
This attribute is used to get/set the efficiency latency control low
threshold. This attribute is in percentages of CPU utilization.
h](j )}(h ``elc_low_threshold_percent``h]j )}(hjV
h]helc_low_threshold_percent}(hjX
hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hjT
ubah }(h ]h ]h"]h$]h&]uh1j hhhKhjP
ubj )}(hhh]j )}(hThis attribute is used to get/set the efficiency latency control low
threshold. This attribute is in percentages of CPU utilization.h]hThis attribute is used to get/set the efficiency latency control low
threshold. This attribute is in percentages of CPU utilization.}(hjn
hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhjk
ubah }(h ]h ]h"]h$]h&]uh1j hjP
ubeh }(h ]h ]h"]h$]h&]uh1j hhhKhj
hhubj )}(h``elc_high_threshold_percent``
This attribute is used to get/set the efficiency latency control high
threshold. This attribute is in percentages of CPU utilization.
h](j )}(h ``elc_high_threshold_percent``h]j )}(hj
h]helc_high_threshold_percent}(hj
hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hj
ubah }(h ]h ]h"]h$]h&]uh1j hhhKhj
ubj )}(hhh]j )}(hThis attribute is used to get/set the efficiency latency control high
threshold. This attribute is in percentages of CPU utilization.h]hThis attribute is used to get/set the efficiency latency control high
threshold. This attribute is in percentages of CPU utilization.}(hj
hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj
ubah }(h ]h ]h"]h$]h&]uh1j hj
ubeh }(h ]h ]h"]h$]h&]uh1j hhhKhj
hhubj )}(h``elc_high_threshold_enable``
This attribute is used to enable/disable the efficiency latency control
high threshold. Write '1' to enable, '0' to disable.
h](j )}(h ``elc_high_threshold_enable``h]j )}(hj
h]helc_high_threshold_enable}(hj
hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hj
ubah }(h ]h ]h"]h$]h&]uh1j hhhKhj
ubj )}(hhh]j )}(h|This attribute is used to enable/disable the efficiency latency control
high threshold. Write '1' to enable, '0' to disable.h]hThis attribute is used to enable/disable the efficiency latency control
high threshold. Write ‘1’ to enable, ‘0’ to disable.}(hj
hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj
ubah }(h ]h ]h"]h$]h&]uh1j hj
ubeh }(h ]h ]h"]h$]h&]uh1j hhhKhj
hhubj )}(hXj Example system configuration below, which does following:
* when CPU utilization is less than 10%: sets uncore frequency to 800MHz
* when CPU utilization is higher than 95%: increases uncore frequency in
100MHz steps, until power limit is reached
elc_floor_freq_khz:800000
elc_high_threshold_percent:95
elc_high_threshold_enable:1
elc_low_threshold_percent:10h](j )}(h9Example system configuration below, which does following:h]h9Example system configuration below, which does following:}(hj
hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj
ubj )}(hhh](h bullet_list)}(hhh](h list_item)}(hFwhen CPU utilization is less than 10%: sets uncore frequency to 800MHzh]j )}(hj h]hFwhen CPU utilization is less than 10%: sets uncore frequency to 800MHz}(hj hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj ubah }(h ]h ]h"]h$]h&]uh1j hj ubj )}(hrwhen CPU utilization is higher than 95%: increases uncore frequency in
100MHz steps, until power limit is reached
h]j )}(hqwhen CPU utilization is higher than 95%: increases uncore frequency in
100MHz steps, until power limit is reachedh]hqwhen CPU utilization is higher than 95%: increases uncore frequency in
100MHz steps, until power limit is reached}(hj/ hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj+ ubah }(h ]h ]h"]h$]h&]uh1j hj ubeh }(h ]h ]h"]h$]h&]bullet*uh1j
hhhKhj
ubj )}(hpelc_floor_freq_khz:800000
elc_high_threshold_percent:95
elc_high_threshold_enable:1
elc_low_threshold_percent:10h]hpelc_floor_freq_khz:800000
elc_high_threshold_percent:95
elc_high_threshold_enable:1
elc_low_threshold_percent:10}(hjK hhhNhNubah }(h ]h ]h"]h$]h&]uh1j hhhKhj
ubeh }(h ]h ]h"]h$]h&]uh1j hj
ubeh }(h ]h ]h"]h$]h&]uh1j hhhKhj
hhubeh }(h ]h ]h"]h$]h&]uh1j hj hhhhhNubeh }(h ] efficiency-vs-latency-tradeoffah ]h"] efficiency vs. latency tradeoffah$]h&]uh1j[ hj] hhhhhKubeh }(h ] intel-uncore-frequency-scalingah ]h"] intel uncore frequency scalingah$]h&]uh1j[ hhhhhhhKubeh }(h ]h ]h"]h$]h&]sourcehuh1hcurrent_sourceN current_lineNsettingsdocutils.frontendValues)}(j` N generatorN datestampN source_linkN
source_urlN
toc_backlinksentryfootnote_backlinksK
sectnum_xformKstrip_commentsNstrip_elements_with_classesN
strip_classesN report_levelK
halt_levelKexit_status_levelKdebugNwarning_streamN tracebackinput_encoding utf-8-sig input_encoding_error_handlerstrictoutput_encodingutf-8 output_encoding_error_handlerj error_encodingutf-8 error_encoding_error_handlerbackslashreplace
language_codeenrecord_dependenciesNconfigN id_prefixhauto_id_prefixid
dump_settingsNdump_internalsNdump_transformsNdump_pseudo_xmlNexpose_internalsNstrict_visitorN_disable_configN_sourcehnj _destinationN
_config_files]7/var/lib/git/docbuild/linux/Documentation/docutils.confafile_insertion_enabled raw_enabledKline_length_limitM'pep_referencesN pep_base_urlhttps://peps.python.org/pep_file_url_templatepep-%04drfc_referencesN rfc_base_url&https://datatracker.ietf.org/doc/html/ tab_widthK trim_footnote_reference_spacesyntax_highlightlong smart_quotessmartquotes_locales] character_level_inline_markupdoctitle_xform
docinfo_xformKsectsubtitle_xform
image_loadinglinkembed_stylesheetcloak_email_addressessection_self_linkenvNubreporterNindirect_targets]substitution_defs}(hhj hj j j j j/ j# j> j2 jM jA j\ jP jk j_ jz jn j j} j j j j j j j j j j j j j j j j j j j j j. j" j= j1 jL j@ j[ jO jj j^ jy jm j j| j j j j j j j j j j j j j j j j j j j j j- j! j< j0 jK j? jZ jN ji j] jx jl j j{ j j j j j j j j j j j j j j j j j j j j j, j j; j/ jJ j> jY jM jh j\ jw jk j jz j j j j j j j j j j j j j j j j j
j j j j+ j j: j. jI j= jX jL usubstitution_names}(amphaposj astj brvbarj bsolj/ centj> colonjM commaj\ commatjk copyjz currenj darrj degj dividej dollarj equalsj exclj frac12j frac14j frac18j frac34j frac38j. frac58j= frac78jL gtj[ halfjj horbarjy hyphenj iexclj iquestj laquoj larrj lcubj ldquoj lowbarj lparj lsqbj lsquoj ltj- microj< middotjK nbspjZ notji numjx ohmj ordfj ordmj paraj percntj periodj plusj plusmnj poundj questj quotj raquoj, rarrj; rcubjJ rdquojY regjh rparjw rsqbj rsquoj sectj semij shyj solj sungj sup1j sup2j sup3j
timesj tradej+ uarrj: verbarjI yenjX urefnames}refids}nameids}(jx ju j- j* j j j j jp jm u nametypes}(jx j- j j jp uh }(ju j] j* j j j0 j j jm j u
footnote_refs}
citation_refs}
autofootnotes]autofootnote_refs]symbol_footnotes]symbol_footnote_refs] footnotes] citations]autofootnote_startKsymbol_footnote_startK
id_counter collectionsCounter}Rparse_messages]transform_messages] transformerN include_log]?Documentation/admin-guide/pm/intel_uncore_frequency_scaling.rst(NNNNta
decorationNhhub.