Menene bambanci tsakanin C-States da P-States na CPU?

A cikin na'urori na zamani, sarrafa wutar lantarki ba sau ɗaya ba ne, amma saitin hanyoyin haɗin gwiwa (C-States da P-Jihohin CPU, da sauransu) cewa tsarin aiki, firmware, da CPU kanta suna amfani da su don daidaita yawan wutar lantarki, zafin jiki, da aiki a ainihin lokacin. Wannan labarin yana warwarewa kuma yana tsara wannan tangle na gajarta don ku iya fahimtar abin da ke faruwa a ƙarƙashin murfin lokacin da kwamfutarku ke adana wuta ko sauri.

Ko da yake kowane masana'anta da dangin CPU suna ƙara taɓawa, tushe na gama gari: ACPI ta bayyana daidaitattun “jihohi” don tsarin, na'urori, da processor. Anan za ku ga bambance-bambance tsakanin C-States da P-States, yadda suke da alaƙa da G/S/D-States, menene tasirin gaske na duniya akan latency, me yasa yan wasa da ƙwararrun audiophiles sukan hana barci mai zurfi, da kuma wadanne kayan aiki masu amfani da ake samu don amfani akan Windows, Linux, da muhalli kamar ESXi.

ACPI a takaice

ACPI (Babban Kanfigareshan da Wutar Lantarki) shine ma'auni wanda ke tsara iko a cikin PC da sabobin, da wancan maye gurbin APM tare da mafi girma iko da granularity. An haife shi daga hannun Intel, Microsoft da Toshiba a cikin 90s kuma sun samo asali don haɗawa da 64-bit, multiprocessing, bas na zamani (PCIe, SATA, USB 3.x) da gano taron (misali, maɓallin wuta).

Kodayake ana amfani da ACPI da farko a cikin dangin x86, an kuma tura shi akan wasu gine-gine. A kan na'urorin hannu na ARM, duk da haka, Ana amfani da dabarun mallakar mallaka (kamar manya. KADAN da gungu iri-iri) don daidaita inganci da amsa dangane da kaya.

Jihohin Duniya da Dakatarwa (G-Jihohin da S- Jihohin)

Kasashen duniya sun bayyana cikakken yanayin tsarin. Mafi mahimmanci shine G0/S0 (Aiki), inda kwamfutar ke aiki. A kan kayan aikin kwanan nan akwai S0ix (matsalolin S0) wanda ke ba da izinin yanayin bacci mai kyau tare da wani ɓangare na barcin SoC, musamman a cikin kwamfyutoci.

• G0/S0: tsarin aiki.
• G1 (Barci): yana rufe S1, S2, S3 (dakatar da RAM) da S4 (hibernate zuwa faifai). S3 yana riƙe da ƙarfin RAM don ci gaba da sauri; S4 yana ja da ƙwaƙwalwar ajiya zuwa ma'ajin mara mara ƙarfi.
• G2/S5 (mai laushi): Rufe ma'ana tare da ƙaramin ƙarfi don ba da damar farkawa ta abubuwan da suka faru (allon madannai, cibiyar sadarwa, da sauransu).
• G3 (Kashe Injini): Rufewar jiki; RTC kawai ke rayuwa a kowane baturi.

Ka tuna cewa Jihohin C-Processor suna rayuwa tsakanin G0/S0: Lokacin da tsarin ya shiga G1, kunshin CPU yana rufe kuma C-states suna daina wasa.

Jihohin Na'ura (D-jihohin)

ACPI kuma tana ayyana yadda mahaɗan ke kwana ko farkawa. D0 yayi daidai da "cikakken aiki", D1/D2 matsakaici ne (dogara da na'ura) da D3 rassan cikin Hot (tare da karin iko, amsa bas) ko Cold (gaba daya a kashe, ba amsa). Wannan yana ba da damar, misali, katin cibiyar sadarwa don tada kwamfutar yayin da wasu na'urori ke barci.

T-Jihohin: Canjin Agogo, Wurin Ƙarshe

Baya ga P da C, akwai Yanayin agogo (T-States): wani nau'i na PWM wanda ke danne bugun jini na ciki a cikin tsari (misali, 1 daga kowane 8), rage aiki ba tare da canza mitar tushe da aka yi tallar ba. An yi niyya azaman ma'aunin zafi ko gaggawa na gaggawa (PROCHOT) kuma ana sarrafa shi ta IA32_CLOCK_MODULATION, tare da sanadi/Logs a cikin MSR_*_PERF_LIMIT_REASONS.

Ko da yake wasu takardun suna la'akari da shi "ba shi da mahimmanci", a aikace Yana ci gaba da bayyana akan kwamfutocin tafi-da-gidanka tare da ingantaccen ƙirar zafi da kuma ƙarƙashin nauyi mai ɗorewa. Idan ka ga Windows yana ba da rahoton "gudu" ƙasa da mafi ƙarancin EIST, akwai yuwuwar T-State mai aiki (gating agogo).

M- Jihohi: Ƙwaƙwalwar ajiya

ACPI kuma tana ba da jihohin ƙwaƙwalwar ajiya don rage yawan amfani da wutar lantarki na tsarin DRAM lokacin da tsarin ke aiki. M0 aiki ne na al'adaM1/M2 da sauran hanyoyi suna tilasta ƙwaƙwalwar ajiya don sabunta kai da rage jinkirin lokaci, rage ƙarfi tare da lattin farkawa. Waɗannan ba su ganuwa ga mai amfani, amma suna ba da gudummawa ga tanadin gabaɗaya.

Processor C-States: Barci da kai

Bari yanzu mu magance batun labarin: C-States da P-States. C- Jihohin sune jahohin kwaya ko fakiti marasa aiki. Mafi girman lambar, da zurfin barci da kuma tanadi mafi girma, amma kuma mafi girman jinkirin farkawa. Ana buƙatar su tare da gata umarni irin su HLT ko MWAIT (na ƙarshe na iya buƙatar Cx a sarari da matsayi), kuma ikon taswirar ya isa OS ta ACPI (_CST).

• C0: al'ada kisa. Wannan shine inda P-jihohin suka shiga wasa.
• C1/C1E (Dakata): core tsayawa, kusan dawowa nan take ku C0; C1E yana rage yawan amfani.
• C2 (Agogon Tsayawa): Ana dakatar da sigina na agogo, dawowa yana ɗaukar ɗan lokaci kaɗan.
• C3 (Barci/Barci mai zurfi): L1/L2 yana juyewa zuwa cache na ƙarshe (LLC) kuma ana kashe manyan agogo; kawai mahimmancin yanayin tsakiya yana kiyaye shi.
• C6 da sama: Za'a iya yin amfani da mahimmancin ƙasa kuma an adana mahallin sa a cikin SRAM da aka keɓe, yana kawo ƙarfin wutar lantarki zuwa ~ 0 V; a kan fita, an mayar da ainihin jihar. Wasu samfura suna fallasa har zuwa C10 akan dandamali na kwanan nan.

Baya ga C-states per nucleus (CC-states), akwai jirgin sama na Kunshin C-jihohin (jihohin PC) wanda ke kashe shingen da aka raba (kamar LLC) lokacin da duk abin da ke ba da izini. Akwai haɗuwa mara inganci (idan ainihin yana cikin C0, fakitin ba zai iya kasancewa a cikin PC6 ba), kuma CPU na iya “inganta” ko “rage” matakin kai tsaye dangane da latency da wuraren zama.

Latency al'amura: An watsar da C1 a cikin ƴan zagayowar dozin kaɗan, yayin da C6/C7 na iya kashe ɗaruruwan miktoci. Don haka, nauyin jinkirin jinkiri (wasanni, sauti na ainihin lokaci, hanyar sadarwar da ake buƙata) suna wahala idan na'urar tana yawan yin barci mai zurfi.

Performance P-Jihohin: Mita da Voltage

Duk da yake C-jihohin suna "barci lokacin da babu aiki," P-jihohin suna "daidaita taki lokacin da Ee, akwai aiki, amma ba ya ɗaukar iyakar.P0 shine mafi girman yanayin aiki (mafi girman mita/voltage), sannan ya zo P1, P2… kowanne tare da raguwar nau'ikan ƙarfin lantarki. Ana bayyana waɗannan tebur zuwa OS ta ACPI (_PSS) kuma MSRs suna sarrafa su kamar IA32_PERF_CTL/IA32_PERF_STATUS.

A tarihi tsarin aiki ya nemi P-States (EIST/SpeedStep akan Intel, PowerNow! akan AMD), amma a yau ya zama ruwan dare. Jihohin Ayyukan Gudanar da Hardware (HWP/Speed ​​​​Shift): OS yana nuna fifiko (aiki / tanadi) kuma CPU yana yanke hukunci a cikin millise seconds daidai ma'ana, tare da ƙwaƙƙwarar ƙima.

Bayani mai mahimmanci: Jihohin P-jihohi da C-jihohin “al’ada” neKuna iya zama a P0 (high mita) kuma, bayan zama mara aiki, shigar da C6. Sabanin haka, a ƙarƙashin ɗaukar nauyi a P2, babu C-States saboda ainihin yana aiwatarwa (C0). Wannan shine dalilin da ya sa yana da kyau a raba "mita/voltage" (P) a hankali a hankali daga "rago" (C).

Daga APM zuwa ACPI: canjin yanayin

APM shine API ɗin da ya gabata wanda aka sarrafa da farko daga BIOS da direbobi. Ya halatta Kashe abubuwan da ba su da aiki kuma a ayyana sauƙaƙan jihohin duniya, amma CPU ba ta cikin ikon sarrafa OS kai tsaye saboda dalilai na tsaro. ACPI ta samo asali zuwa mafi ƙaƙƙarfan ƙira, ingantaccen tsari, tare da kwatancen tebur, sarrafa ƙwanƙwasa, da kusancin haɗin gwiwa tsakanin firmware, OS, da hardware.

Yadda ake shiga da fita C-States

Lokacin da mai tsara jadawalin ba shi da zaren zaren da aka shirya, yana aiwatar da HLT ko MWAIT tare da alamar C-State da aka yi niyya; Katsewa "karya" barci kuma mayar da ainihin zuwa C0. Ana zubar da caches masu zaman kansu a C3; Ana ajiye mahallin zuwa SRAM a C6 kuma an saukar da wutar lantarki zuwa sifili. Wasu CPUs suna aiwatar da Hanyar Katsewar Power Aware (PAIR) zuwa hanyar katsewa zuwa riga mai aiki da muryoyi (don adanawa) ko zuwa saƙon da ba ya aiki (don aiki), kamar yadda ya dace.

Turbo, TDP da iyakoki

Masu sarrafawa sun ayyana TDP cewa tsarin sanyaya dole ne ya iya tarwatsewa bisa ga dorewa (PL1: amintaccen matsakaicin iko). A sama, manyan windows masu ƙarfi na iya shiga (PL2, da ƙarin matakan kamar PL3 / PL4 dangane da dandamali) don iyakanceccen lokaci. Idan akwai thermal da lantarki headroom, core iya wuce tushe mita via Turbo, ko da Siffar asymmetric (ƙarin turbo tare da ƙananan muryoyi masu aiki).

Lokacin da yanayin zafi ya wuce kofa ko VRM/power ya buƙaci shi, Ana iya kunna PROCHOT kuma shigar da T-State ko yanke mitar don kare guntu. Wannan hali ya zama ruwan dare a cikin siraran kwamfyutocin.

Windows: Tsare-tsaren Wutar Lantarki, Karatu, da Ma'auni

Windows tayi tsare-tsare kamar "Energy Savings", "Balanced" da "High Performance". Na farko yana so ƙananan jihohin P-jihohi da ƙarfi da barci mai daɗiNa uku yana kula da mitoci masu yawa kuma yana guje wa faɗuwar latency akan ƙimar inganci. "Balanced" yana ƙoƙarin tsaka-tsaki.

A cikin Task Manager, "gudun" shine ma'aunin roba wanda Matsakaicin kowane tushe kuma yana la'akari da aikin daidaitawa idan akwai T-States. Yana iya wuce tushe (Turbo) ko faɗuwa ƙasa da mafi ƙarancin EIST (gating). Don ci-gaban telemetry, ma'aunin "Bayanin Mai sarrafawa(_Total)%% Performance Processor" yana nuna adadin ingantaccen aiki ta CPU.

Akwai abubuwan amfani don tantance ko daidaitawa: CPU-Z (babban bayanai), HWiNFO (sensors), Makasabari (agogo, C-States da core da PROCHOT/modulation iko), ko ParkControl (core parking tuning/C-states) wanda ke taɓa ma'aunin tsarin wutar lantarki mai ɓoye (powercfg yana ba da damar gyara "IDLE_PROMOTE/DEMOTE", da sauransu).

Linux: cpupower, turbostat da CoreFreq

A cikin Linux, kayan aikin kamar CPU iko nuna gwamnoni, mita mita da latencies mika mulki; turbostat yana nuni da MSRs, ainihin dalilan iyaka (MSR_CORE_PERF_LIMIT_REASONS), da mazauna ta C-State; kuma CoreFreq yana ba da cikakken ra'ayi na cikakken mitoci, C-States da Turbo a kowace core/kunki.

Nuance mai amfani: akan wasu kwamfutoci, direba intel_idle na iya watsi da ƙuntatawa na BIOS sama da C- Jihohin kuma suna amfani da teburin nasu. A wasu, firmware ta “kulle” mafi zurfin C-state da aka ba da izinin OS ta MSR.

BIOS / UEFI da Bayanan martaba: Wanene Gaskiyar Aiki?

A cikin saitunan BIOS/UEFI yawanci suna bayyana Maɓallin maɓalli: EIST/SpeedStep, TurboBoost da CPU C-StatesBugu da ƙari, yawancin sabobin suna ba ka damar zaɓar bayanan martaba: "Mafi girman Aiki" (komai a mafi kyawunsa, tare da ƙarancin latencies) ko "OS Sarrafa/Custom," inda hypervisor ko OS ke mulkin P/C-States. Zaɓin "Yanayin Sarrafa OS" yana ba da hankali ga tsarin aiki.

Idan kuna amfani da hypervisors kamar ESXi, yana da kyau a haɗa Yanayin Gudanar da OS a cikin BIOS tare da shirin "High Performance". na hypervisor lokacin da makasudin shine matsi aikin (misali tare da NSX-T, Edge Nodes, ko ayyukan jinkirin latency). A cikin wannan yanayin, zaku ga P-State 0 akai-akai da C-States iyakance ga C0/C1; tare da shirin "Balanced", mai watsa shiri zai dogara da ƙananan P-States da zurfin C-States.

Don taƙaita wannan duka C-States da P-States rikici: ACPI ta bayyana firam, C-Jihohin suna adana ƙarfi lokacin da babu aiki, P-States daidaita babban / ƙananan kaya a ƙarƙashin kaya, T-Jihohin suna adana rana cikin matsanancin zafi, kuma M-Jihohi suna aske watts kashe ƙwaƙwalwar ajiya. Makullin shine zaɓi bayanin martaba mai kyau don amfani da ku., auna tare da ingantattun kayan aikin kuma, idan ya cancanta, saita iyakoki masu ma'ana akan zurfin hutu.

Labari mai dangantaka:

Stadby na zamani yana zubar da baturi yayin barci: yadda ake kashe shi

Daniel Terrasa

Edita ya ƙware a fannin fasaha da al'amuran intanet tare da gogewa fiye da shekaru goma a cikin kafofin watsa labaru na dijital daban-daban. Na yi aiki a matsayin edita da mahaliccin abun ciki don kasuwancin e-commerce, sadarwa, tallan kan layi da kamfanonin talla. Na kuma yi rubutu a shafukan yanar gizo na tattalin arziki, kudi da sauran fannoni. Aikina kuma shine sha'awata. Yanzu, ta hanyar labarai na a ciki Tecnobits, Ina ƙoƙarin bincika duk labarai da sababbin damar da duniyar fasahar ke ba mu kowace rana don inganta rayuwarmu.