Kugovera pane Stack

Nei Kugoverwa kweStack Kuchiri Kunetsa muInjiniya Yemazuva Ano Software

Pese apo application yako ichiita chikumbiro, inogadzira shanduko, kana kufonera basa, sarudzo yakanyarara iri kuitwa kuseri kwezviitiko: iyi data inofanirwa kugara mundangariro kupi? Kwemakumi emakore, kugoverwa kwemasitaki kwave kuri imwe yeanomhanyisa, anonyanya kufanofungidzira nzira dzekurangarira anowanikwa kune vanogadzira zvirongwa - zvakadaro zvinoramba zvisinganzwisisike. Munguva yenguva inodzorwa, vanonhonga marara, uye zvivakwa zvemakore, kunzwisisa kuti sei uye riini kugovera pachitunha kunogona kureva mutsauko pakati pechishandiso chinobata 10,000 vanoshandisa panguva imwe chete uye chinobata pasi pemazana mashanu. PaMewayz, apo chikuva chedu chinoshanda pamusoro pe138,000 mamemodules emumodule wememodule ye20 , 20 , 20 , 000 mabhizinesi akaverengeka.

Stack vs. Heap: The Fundamental Trade-Off

Memory munzvimbo zhinji dzehurongwa hwakakamurwa kuita matunhu maviri ekutanga: stack uye murwi. Iyo stack inoshanda seyekupedzisira-mukati, yekutanga-kunze (LIFO) data chimiro. Kana basa radaidzwa, "frame" nyowani inosundirwa pastack ine zvinosiyana zvemunharaunda, kero dzekudzosera, uye maparamita ebasa. Kana basa iroro radzoka, furemu yese inobviswa ipapo ipapo. Hapana kutsvaga, hapana kuchengeta mabhuku, hapana kupatsanurwa — chingori gadziriso imwe chete.

Murwi, nekupesana, idziva hombe rendangariro uko kugovaniswa uye kugoverwa kunogona kuitika mune chero kurongeka. Uku kuchinjika kunouya nemubhadharo: mugoveri anofanira kuteedzera kuti ndeapi mabhuraki emahara, kubata kupatsanuka, uye mumitauro mizhinji, vimba nemuunganidzi wemarara kuti atore ndangariro dzisina kushandiswa. Kugoverwa kwemurwi muchirongwa cheC chaitora nguva yakareba kusvika gumi kusvika makumi maviri pane kugovaniswa. Mumitauro inounganidzwa marara yakaita seJava kana C#, musoro wepamusoro unogona kutokwira zvakanyanya kana kumbomira kuunganidzwa kwakaiswa.

Kunzwisisa kutengeserana uku hakusi kwedzidzo chete. Paunenge uchigadzira software inogadzira zviuru zvetransaction pasekondi yega yega - ingave iyo invoice injini, chaiyo-nguva analytics dashboard, kana CRM inobata zvinhu zvakawanda zvinouya kunze kwenyika - kusarudza nzira yekugovera kwayo nzira dzinopisa zvinokanganisa nguva dzekupindura uye mutengo wezvivakwa.

Maitiro Anoita Stack Allocation Chaizvoizvo

Padanho rehardware, mazhinji ma processor ekuvaka anotsaurira register (iyo stack pointer) kuteedzera kumusoro kwazvino kwestack. Kugovera ndangariro pachitunha kuri nyore sekudzikisa ichi chinongedzo nenhamba inodiwa yemabhaiti. Deallocation ndiyo inodzosera kumashure: wedzera chinongedzo. Hapana metadata misoro, hapana rondedzero yemahara, hapana coalescing yemabhuraki ari padyo. Ichi ndicho chikonzero kugoverwa kwezvimedu kuchiwanzotsanangurwa sekuve neO(1) inogara-nguva-yekuita nepamusoro-soro isina basa.

Funga nezvebasa rinoverengera huwandu hwechinhu cheinivhoisi. Inogona kuzivisa mashoma emunharaunda: huwandu hwehuwandu, mutengo weyuniti kutenderera, mutero wemutero, uye mhedzisiro. Zvose zvina zvakakosha zvinosundirwa pane stack kana basa racho rapinda uye rinodzoserwa pakarepo parinobuda. Hupenyu hwese hunotemerwa uye hunoda zero kupindira kubva kumugadziri wepurogiramu kana anonhonga marara.

Muono wakakosha: Kugovaniswa kwemastaki hakusi kukurumidza chete — kunotarisika. Mune maitiro-akakosha masisitimu, kufanotaura kunowanzo kukosha kupfuura kumhanya mbishi. Basa rinogara rinopedzwa mumamicroseconds maviri rakakosha kudarika iro rinoita avhareji 1 microsecond asi pano neapo rinokwira kusvika kumamicroseconds makumi mashanu nekuda kwekumbomira kwekuunganidza marara.

Nguva Yekufarira Stack Allocation

Haasi chidimbu chese che data chiri pastack. Stack memory inogumira (kazhinji pakati pe1 MB ne8 MB pashinda, zvichienderana nehurongwa hwekushandisa), uye data yakagoverwa pachitunha haigone kurarama basa rakaigadzira. Zvisineyi, pane mamiriro akajeka apo kugoverwa kwe stack ndiyo sarudzo yepamusoro.

• Makaunda enguva pfupi: Makaunda, accumulators, mabhafa enguva pfupi ari pasi pemakirobhayithi mashoma, uye loop indices ndeyezvakasikwa inokwana stack. Izvo zvakagadzirwa, kushandiswa, uye kuraswa mukati mechikamu chimwe chete chebasa.
• Fixed-size data structures: Mitsetse ine saizi inozivikanwa yekuunganidza-nguva, zvidimbu zvidiki, uye mhando dzeukoshi zvinogona kuiswa pachituru pasina njodzi yekufashukira. 256-byte buffer yekufometa tambo yemazuva inonyatso kumirira.
• Performance-critical inner loops: Kana basa richinzi mamirioni enguva pasekondi - senge injini yekuverenga mitengo ichidzokorodza pamakatalogi ezvigadzirwa - kubvisa mirwi yakagoverwa muloop body kunogona kupa 3x kusvika 10x kuvandudzwa kwehuwandu.
• Nzira dzenguva chaiyo kana kuti dzanonoka: Kugadziriswa kwekubhadhara, zvigadziriso zvedashboard, uye zviziviso zvinotumira zvese zvinobatsira kubva mukudzivisa kumira kusingafungidzirwe kuunganidzwa kwemarara.
• Recursive algorithms ane kudzika kwakaganhurwa: Kana uchikwanisa kuvimbisa kudzika kwekudzokorora kunogara mukati memiganhu yakachengeteka, mafuremu akagoverwa anochengeta mabasa anodzokororwa nekukurumidza uye nyore.

Mukuita, vagadziri vemazuva ano vakanaka kwazvo pakugadzirisa mashandisirwo e stack. Matekiniki akaita sekuongorora kutiza muGo uye Java's JIT compiler inogona kufambisa mirwi yekugovera kune stack kana muunganidzi achiratidza kuti data haitize chiyero chebasa. Kunzwisisa magadzirirwo aya kunoita kuti unyore kodhi yakachenesa uchiri kubatsirwa ne stack performance.

Njongo Dzakajairwa uye Madziviserwe nadzo

Chipembenene chinonyanyozivikanwa chine chekuita ne stack kupfachukira - kugovera data rakawanda kupfuura rinogona kubata, kazhinji kuburikidza nekudzokororwa kusingaverengeki kana hukuru hwakakura hwenzvimbo. Munzvimbo yekugadzira, stack inofashukira kazhinji inorovera shinda kana maitiro ese pasina nzira yekudzoreredza yakanaka. Ichi ndicho chikonzero masisitimu uye masisitimu ekushandisa achiisa miganhu yesaizi.

Imwe gomba risinganzwisisike kudzorera zvinongedzo kana mareferensi kune data yakagoverwa. Nekuti stack memory inodzoserwa nguva iyo basa radzoka, chero chinongedzo kune iyo ndangariro chinova chinorembera chinongedzo. MuC neC ++, izvi zvinotungamira kune hunhu husina kutsanangurwa hungaite senge hunoshanda mukuyedzwa asi huchikundikana nenjodzi mukugadzira. Rust's borrow checker inobata kirasi yemhosho panguva yekunyora, chinova chimwe chikonzero nei mutauro wawana simba rekugadzirisa masisitimu.

Nyaya yechitatu inosanganisira kuchengetedza shinda. Tambo yega yega inowana murwi wayo, zvinoreva kuti stack-yakagoverwa data ndeyemukati-yenzvimbo. Izvi ndizvo chaizvo zvakanakira mune dzakawanda zviitiko - hapana makiyi anodiwa kuti uwane akasiyana emunharaunda. Nekudaro, vanogadzira dzimwe nguva vanoita mhosho yekuyedza kugovera data-yakagoverwa pakati petambo, zvichitungamira kumamiriro emujaho kana kushandisa-mushure-yemahara tsikidzi. Kana data ichida kugovaniswa pane shinda kana kuramba kupfuura kufona, murwi ndiyo sarudzo yakakodzera.

Stack Allocation MuMitauro neZvirongwa

Mitauro yezvirongwa yakasiyana inobata stack allocation ine madhigirii akasiyana ejekerere. MuC neC ++, mugadziri ane hutongi hwakajeka: zvinoshanduka zvemunharaunda zvinoenda pane stack, uye malloc kana itsva inoisa data pamurwi. MuGo, muunganidzi anoita ongororo yekutiza kuti asarudze otomatiki, uye goroutines anotanga nediki 2 KB stacks inokura zvine simba - mhinduro inoyevedza inoenzanisa kuchengeteka nekuita. PHP, iyo mutauro inosimbisa masimba seLaravel, inogovera kukosha kwakawanda kuburikidza nemukati meZend Engine memory maneja, asi kunzwisisa misimboti yepasi kunobatsira vanogadzira kunyora kodhi inoshanda zvakanyanya kunyangwe padanho rekushandisa.

Kuzvikwata zvinovaka mapuratifomu akaomarara - sechikwata cheinjiniya kuMewayz, uko chikumbiro chimwe chete chingapfuura pfungwa dzeCRM, kuverenga kwemainvoisi, kuverengerwa kwemutero wemihoro, uye kuunganidzwa kwekuongorora - idzi sarudzo dzakaderera. Kana 207 modules inogovera nguva yekumhanya, kuderedza kugovaniswa kwechikumbiro chega chega kunyangwe 15% kunogona kuturikira kudzikiswa zvine mutsindo mumutengo weseva uye kuvandudzwa kunoyerwa munguva dzekupindura kune vashandisi vekupedzisira vanotonga mabhizinesi avo pachikuva.

JavaScript neTypeScript, iyo ine simba kumberi kwemazuva ano uye Node.js backends, inotsamira chose pamuunganidzi wemarara weinjini yeV8 pakuronga ndangariro. Vagadziri havagone kugovera zvakananga pane stack, asi V8's optimizing compiler (TurboFan) inoita stack kugoverwa mukati kune hunhu hwaanogona kuratidza kuti ndehwenguva pfupi. Kunyora mabasa madiki, akachena aine machinjiro emunharaunda anopa injini mukana wakanaka wekushandisa zvigadziriso izvi.

Maitiro Anoshanda ekuderedza Kufurira kwemurwi

Kunyangwe uchishanda nemutauro wepamusoro-soro pausingakwanise kudzora zvakananga stack maringe nekugoverwa kwemurwi, unokwanisa kushandisa mapatani anoderedza kumanikidzwa kwemurwi uye worega nguva yekumhanya ichiwedzera zvine hukasha.

1. Sarudza mhando dzemhando pane dzereferensi apo mutauro unozvitsigira. MuC#, kushandisa struct pachinzvimbo checlass yezvinhu zvidiki, zvinogaro gadzirwa zvinozvichengeta pastack. MuGo, kupfuudza zvidimbu zvidiki nekukosha kwete neinongedzo kunoita zvakafanana.
2. Rega kugovera mukati mezvikochekedzo zvakasimba. Pre-gova mabhafa uye woashandisa zvakare pakudzokorora. Kana iwe uchida chidimbu chenguva pfupi kana mutsara mukati mejira rinomhanya ka100,000, rigovere kamwe chete pamberi pe loop uye rigadzirise pakudzokorora kwega kwega.
3. Shandisai kubatanidza zvinhu zvezvinhu zvinogarogadzirwa kana kuparadzwa. Dhetabhesi yekubatanidza madziva ndiwo muenzaniso wekare, asi patani yacho inoshanda zvakaenzana kuzvinhu zvinokumbirwa neHTTP, mabhafa ekutevedza, uye zvidimbu zvemakomputa.
4. Profile usati wagadzirisa. Zvishandiso zvakaita seGo's pprof, Java's async-profiler, kana PHP's Blackfire inogona kunongedza panowanikwa mari. Kugadzirisa pasina kuprofilita data kune njodzi yekushandisa kuedza munzira dzinotonhora dzisingawanzo itwa.
5. Nyeredza maalocators enhandare ekushanda kwebatch. Paunenge uchigadzira batch yemarekodhi - sekugadzira 500 invoice kana kuunza macontacts zviuru gumi - mumiriri wearena anobata chivharo chikuru chendangariro obva aiburitsa nekukurumidza senge stack, obva asunungura block yese pakarepo.

Mazano aya haasi edzidziso chete. Kana SaaS mapuratifomu achibata basa renyika chairo - muridzi webhizinesi diki anogadzira mainvoice epamwedzi, maneja weHR achimhanyisa mubhadharo wevashandi mazana maviri, timu yekushambadzira inoongorora mashandiro emushandirapamwe mumatanho - iyo inowedzeredza mhedzisiro yehunyanzvi hwekurangarira manejimendi ndeye snappier, inoteedzera ruzivo iyo vashandisi vanonzwa kunyangwe vasina kumbofunga nezve zviri kuitika pasi.

Kuvaka Performance-Conscious Software paChikero

Stack allocation ndechimwe chidimbu chepuzzle yakakura kwazvo, asi chiri chekutanga. Kunzwisisa kuti ndangariro dzinoshanda sei padanho rakaderera kunopa mainjiniya mamodheru epfungwa avanoda kuti vaite sarudzo dziri nani pane yega yega stack - kubva pakusarudza zvimiro zvedata uye kugadzira maAPIs kusvika pakugadzirisa zvivakwa uye kuseta zviwanikwa zvezvishandiso zvemasevhisi akaiswa mumidziyo.

Kune mabhizinesi anovimba nemapuratifomu akaita seMewayz kuti aite mabasa avo ezuva nezuva, mubairo weiyi sarudzo dzeinjiniya unobatika: kukurumidza kurodha mapeji, kupindirana kwakapfava, uye chivimbo chekuti sisitimu haizodzikisire pasi pepamusoro mutoro. Kana imwe moduli yekubhuka ichida kutarisa kuwanikwa kwemakarenda akawanda munguva chaiyo, kana dashibhodhi reanalytics richiunganidza data pamayuniti akawanda emabhizinesi, zano rekutanga rekurangarira rinonyanya kukosha kupfuura zvinozivikanwa nevashandisi vazhinji.

Iyo software yakanakisa inonzwa isingaite kushandisa chaizvo nekuti vagadziri vayo vakadikitira izvo zvinoramba zvisingaonekwe. Stack allocation — inokurumidza, deterministic, uye inoyevedza mukupfava kwayo — ndechimwe chemashoko akakodzera kunzwisiswa zvakadzama, ungave uri kunyora chirongwa chako chekutanga kana kugadzira chikuva chinoshandira zviuru zvemabhizinesi pasi rese.

Mibvunzo Inowanzo bvunzwa

Chii chinonzi stack allocation uye nei zvine basa?

Stack allocation inzira yekurangarira ndangariro uko data rinochengetwa mune yekupedzisira-mukati, yekutanga-kunze chimiro chinongo tungamirirwa nekuyerera kwechirongwa. Izvo zvine basa nekuti stack-yakagoverwa ndangariro inokurumidza kupfuura kugoverwa kwemurwi - hapana muunganidzi wemarara pamusoro, hapana kupatsanurwa, uye deallocation inoitika ipapo kana basa radzoka. Kune maapplication akakosha, kunzwisisa kugoverwa kwe stack kunogona kuderedza zvakanyanya latency uye kunatsiridza mabudiro.

Ndirini pandinofanira kushandisa stack allocation pamusoro pemurwi wekugoverwa?

Shandisa stack allocation kune zvidiki, zvenguva pfupi zvinosiyana zvine saizi inozivikanwa panguva yekugadzira - senge ma integers emunharaunda, structs, ne-fixed-size arrays. Kugoverwa kwemurwi kwakanyatsokodzera zvimiro zvakakura zvedata, kuunganidzwa kwakakura, kana zvinhu zvinoda kurarama kupfuura basa rakazvigadzira. Murairo wakakosha: kana hupenyu hwedata huchienderana nechiyero chebasa uye saizi yaro inotarisika, stack ndiyo inenge iri sarudzo inokurumidza.

Mhosho dzekufashukira dzinogona kudzivirirwa mumapurogiramu ekugadzira?

Ehe, zvikanganiso zvekufashukira zvinodzivirirwa nemaitiro einjiniya akarangwa. Dzivisa kudzokororwa kwakadzika kana kusingaverengeki, dzikamisa migove mikuru yenzvimbo, uye shandisa algorithms inodzokororwa pazvinogoneka. Mitauro mizhinji uye masisitimu anoshanda anokuita kuti ugadzirise masaizi ekugumira. Maturusi ekuona uye zvigadziriso zvepuratifomu zvakaita seMewayz, 207-module bhizinesi OS inotangira pa$19/mo, inogona kubatsira zvikwata kuronda hutano hweapps uye kubata madhigirii emashandiro nekukasika.

Mitauro yemazuvano ichiri kubatsirwa here nekugoverwa kwemastaki?

Chokwadi. Kunyangwe mitauro ine nguva dzekumhanya - senge Go, Rust, C #, uye Java - shandisa ongororo yekupukunyuka kuona kana machinjiro anogona kugovaniswa panzvimbo yekupihwa murwi. Rust inomanikidza stack-yekutanga kugoverwa kuburikidza nemuridzi wayo modhi, uye Go's compiler inosimudzira zvine hukasha. Kunzwisisa makanika aya kunobatsira vanogadzira kunyora kodhi iyo vagadziri vanogona kukwirisa zvakanyanya, zvichikonzera kuderera kwekushandiswa kwendangariro uye nekukasira nguva dzekuita.