I-hard drive yokuqala emhlabeni, i-IBM RAMAC 305, eyakhululwa ngo-1956, yayiqukethe kuphela i-5 MB yedatha, futhi inesisindo esingu-970 kg futhi yayiqhathaniswa ngobukhulu nesiqandisi sezimboni. Izinkampani ezihamba phambili zesimanje zingaziqhenya ngomthamo osuvele ungama-20 TB. Cabanga nje: eminyakeni engu-64 eyedlule, ukuze kuqoshwe lesi samba solwazi, kwakuzothatha ngaphezu kwezigidi ezingu-4 i-RAMAC 305, futhi ubukhulu besikhungo sedatha esidingekayo ukuze sihlangabezane nabo, ngabe sedlula amakhilomitha-skwele angu-9, kuyilapho namuhla encane. ibhokisi elinesisindo esingamagremu angama-700! Ngezindlela eziningi, lokhu kwanda okumangalisayo kokuminyana kwesitoreji kufinyelelwe ngenxa yokuthuthukiswa kwezindlela zokuqopha kazibuthe.
Kunzima ukukukholelwa, kodwa ngokuyisisekelo ukwakheka kwama-hard drive akukashintshi cishe iminyaka engama-40, kusukela ngo-1983: kungaleso sikhathi lapho i-RO3,5 yokuqala eyi-hard drive engu-351-intshi, eyakhiwe yinkampani yaseScotland iRodime, yabona ukukhanya. Le ngane ithole amapuleti kazibuthe amabili angu-10 MB lilinye, okungukuthi, ikwazile ukubamba idatha ephindwe kabili kunaleyo ebuyekeziwe engu-412-inch ST-5,25, ekhishwe yi-Seagate ngonyaka ofanayo kumakhompyutha womuntu we-IBM 5160.
I-Rodime RO351 - i-hard drive yokuqala engu-3,5-intshi emhlabeni
Naphezu kokusha nosayizi ohlangene, ngesikhathi sokukhululwa kwe-RO351, cishe akekho owayeyidinga, futhi yonke imizamo kaRodime yokuthola indawo emakethe ye-hard drive yehlulekile, yingakho inkampani yaphoqeleka ukuba iyeke ukusebenza. ngo-1991, sebethengise cishe zonke izimpahla ezikhona futhi behlisa isimo saba ncane. Kodwa-ke, u-Rodime wayengahloselwe ukuqothuka: ngokushesha abakhiqizi abakhulu kunabo bonke baqala ukuphendukela kuye, befisa ukuthola ilayisense yokusebenzisa ifomu eligunyazwe ngabakwaScots. I-3,5" manje isiyindinganiso yemboni yakho kokubili ama-HDD omthengi nawebhizinisi.
Ngokufika kwamanethiwekhi e-neural, Ukufunda Okujulile kanye ne-Inthanethi Yezinto (IoT), umthamo wedatha odalwe isintu usuqale ukukhula njengeqhwa. Ngokwezilinganiso ze-IDC ye-ejensi yokuhlaziya, ngo-2025 inani lolwazi olukhiqizwa kokubili abantu ngokwabo kanye namadivayisi aseduze nathi lizofinyelela ku-175 zettabytes (1 Zbyte = 1021 bytes), futhi lokhu naphezu kokuthi ngo-2019 bekuyi-45. I-Zbytes, ngo-2016 - 16 Zbytes, futhi emuva ngo-2006, inani eliphelele ledatha elikhiqizwe kuwo wonke umlando obonakalayo alizange lidlule ku-0,16 (!) Zbytes. Ubuchwepheshe besimanje busiza ukubhekana nokuqhuma kolwazi, phakathi kwazo izindlela ezithuthukisiwe zokuqopha idatha akuzona ezokugcina.
I-LMR, PMR, CMR kanye ne-TDMR: yini umehluko?
Umgomo wokusebenza kwama-hard drive ulula kakhulu. Amapuleti ensimbi azacile ambozwe ngongqimba lwezinto ezisetshenziswa yi-ferromagnetic (into eyikristalu engakwazi ukuhlala idonsa uzibuthe ngisho nalapho ingekho inkambu kazibuthe yangaphandle ezingeni lokushisa elingaphansi kwephoyinti le-Curie) anyakaze ngokuhlobene nebhulokhi lamakhanda okurekhoda ngesivinini esikhulu (5400 rpm noma Okuningi). Lapho ugesi usetshenziswa ekhanda lokubhala, kuphakama inkambu kazibuthe eshintshanayo, eshintsha isiqondiso sevector yamagnetization yezizinda (izifunda ezihlukene zendaba) ze-ferromagnet. Ukufundwa kwedatha kwenzeka ngenxa yesenzo sokungeniswa kwe-electromagnetic (ukunyakaza kwezizinda okuhlobene nenzwa kubangela ukuvela kokushintshana kwamandla kagesi ekugcineni), noma ngenxa yomphumela omkhulu we-magnetoresistive (ukumelana kukagesi kwenzwa kuyashintsha ngaphansi isenzo senkundla kazibuthe), njengoba kusetshenziswa kumishini yokugcina izinto yesimanje. Isizinda ngasinye sifaka ikhodi eyodwa yolwazi, sithatha inani elinengqondo elithi "0" noma "1" kuye ngokuthi ikuphi i-vector yamagnetization.
Isikhathi eside, ama-hard drive asebenzisa indlela ye-Longitudinal Magnetic Recording (LMR), lapho i-domain magnetization vector ilele endizeni ye-magnetic platter. Naphezu kokusebenziseka kalula okulinganiselwe, lobu buchwepheshe bube nesiphambeko esibalulekile: ukuze unqobe ukuphoqelela (ukuguqulwa kwezinhlayiya zikazibuthe ziye endaweni yesizinda esisodwa), indawo ekhangayo ye-buffer zone (okuthiwa indawo yonogada) kwadingeka ishiywe phakathi. amathrekhi. Ngenxa yalokho, ukuminyana okuphezulu kokuqopha okutholwe ekugcineni kwalobu buchwepheshe bekuyi-150 Gb/in2 kuphela.
Ngo-2010, i-LMR yacishe yathathelwa indawo yi-PMR (Perpendicular Magnetic Recording - perpendicular magnetic recording). Umehluko omkhulu phakathi kwalobu buchwepheshe kanye nokuqoshwa kazibuthe kwe-longitudinal ukuthi i-vector magnetic directivity yesizinda ngasinye itholakala ku-engeli engu-90 Β° ebusweni bepuleti kazibuthe, okwenza kube nokwenzeka ukunciphisa kakhulu igebe phakathi kwamathrekhi.
Ngenxa yalokhu, ukuminyana kokurekhoda kwedatha kuye kwanda kakhulu (kufika ku-1 Tbit / inch2 kumadivayisi wesimanje), kuyilapho kungadeli izici zejubane nokuthembeka kwama-hard drive. Njengamanje, ukuqoshwa kazibuthe okuyi-perpendicular yiyona ehamba phambili emakethe, yingakho futhi kuvame ukubizwa ngokuthi yi-CMR (Ukuqoshwa Okujwayelekile Kwezibuthe - ukurekhoda okujwayelekile kazibuthe). Ngesikhathi esifanayo, umuntu kufanele aqonde ukuthi awukho nhlobo umehluko phakathi kwe-PMR ne-CMR - lena inguqulo ehlukile yegama.
Uma ubheka ukucaciswa kwama-hard drive esimanje, ungase futhi uhlangane nesifinyezo esifihlekile se-TDMR. Ikakhulukazi, lobu buchwepheshe busetshenziswa amadrayivu ekilasi lebhizinisi . Ngokombono wefiziksi, i-TDMR (emele i-Two Dimensional Magnetic Recording - ukuqoshwa kazibuthe okunezinhlangothi ezimbili) ayihlukile ku-PMR evamile: njengangaphambili, sibhekene namathrekhi angaphambanisi, izizinda eziqondiswe kuzo zonke izingxenye ze-perpendicular. endizeni yamapuleti kazibuthe. Umehluko phakathi kobuchwepheshe ulele endleleni yokufunda ulwazi.
Kubhulokhi yamakhanda kazibuthe wamadrayivu aqinile adalwe kusetshenziswa ubuchwepheshe be-TDMR, ikhanda ngalinye lokurekhoda linezinzwa zokufunda ezimbili ezifunda kanyekanye idatha yethrekhi ngayinye edlulisiwe. Lokhu kungasebenzi kabusha kuvumela isilawuli se-HDD ukuthi sihlunge ngempumelelo umsindo kagesi obangelwa yi-Intertrack Interference (ITI).
Ukuxazulula inkinga nge-ITI kunikeza izinzuzo ezimbili ezibaluleke kakhulu:
- ukuncishiswa kwesici somsindo kuvumela ukukhulisa ukuminyana kokurekhoda ngokunciphisa ibanga phakathi kwamathrekhi, ukunikeza inzuzo kumthamo ophelele kufika ku-10% uma kuqhathaniswa ne-PMR evamile;
- Ihlanganiswe nobuchwepheshe be-RVS kanye ne-actuator encane enezikhundla ezintathu, i-TDMR imelana ngempumelelo nokudlidliza okubangelwa amadrayivu aqinile, okusiza ukuzuza amazinga angashintshi okusebenza ngisho nasezimweni ezinzima kakhulu.
Iyini i-SMR futhi idliwa ngani?
Ubukhulu bekhanda lokubhala cishe bubukhulu ngokuphindwe izikhathi ezingu-1,7 kunobukhulu benzwa efundiwe. Umehluko onjalo ohlaba umxhwele uchazwa kalula: uma imojula yokurekhoda yenziwa encane nakakhulu, amandla okusebenza kazibuthe angeke anele ukwenza uzibuthe izizinda zongqimba lwe-ferromagnetic, okusho ukuthi idatha ngeke zigcinwe. Endabeni yenzwa yokufunda, le nkinga ayiveli. Ngaphezu kwalokho, ukwenziwa kwayo okuncane kwenza kube lula ukwehlisa umthelela we-ITI okukhulunywe ngawo ngenhla ohlelweni lokufunda ulwazi.
Leli qiniso lakha isisekelo sokuqoshwa kukazibuthe okufakwe ithayela (Shingled Magnetic Recording, SMR). Ake siqonde ukuthi isebenza kanjani. Uma usebenzisa i-PMR yendabuko, ikhanda lokubhala liyagudluzwa ngokuhlobene nethrekhi ngayinye yangaphambilini ngebanga elilingana nobubanzi bayo + ububanzi besikhala sokuzivikela (isikhala sokuqapha).
Uma usebenzisa indlela yamathayili yokurekhoda kazibuthe, ikhanda lokurekhoda liya phambili kuphela ingxenye yobubanzi balo, ngakho ithrekhi ngayinye yangaphambilini ibhalwa ngaphezulu ngalena elandelayo: amathrekhi kazibuthe ayagqina njengamathayela ophahleni. Le ndlela yenza kube nokwenzeka ukuba kuqhutshekwe nokwandisa ukuminyana kokurekhoda, kunikeze inzuzo yamandla efinyelela ku-10%, kuyilapho ingaphazamisi inqubo yokufunda. Isibonelo yilesi β amadrayivu okuqala emhlabeni angu-3.5-intshi 20 TB ane-SATA/SAS interface, ukubonakala kwawo okwenzekile ngenxa yobuchwepheshe obusha bokuqopha kazibuthe. Ngakho-ke, ukushintshela kumadiski e-SMR kukuvumela ukuthi ukhuphule ukuminyana kokugcinwa kwedatha kuma-racks afanayo ngezindleko ezincane zokuthuthukisa ingqalasizinda ye-IT.
Naphezu kwenzuzo enkulu kangaka, i-SMR inobubi obusobala. Njengoba amathrekhi kazibuthe edlula omunye komunye, lapho ubuyekeza idatha, kuzodingeka ukuthi ubhale kabusha hhayi kuphela isiqeshana esidingekayo, kodwa futhi nawo wonke amathrekhi alandelayo angaphakathi kucwecwe kazibuthe, umthamo wawo ongadlula ama-terabytes angu-2, ogcwele ukwehla okukhulu. ekusebenzeni.
Ukuhlanganisa inani elithile lamathrekhi abe amaqembu ahlukene abizwa ngokuthi amazoni kusiza ukuxazulula le nkinga. Nakuba le ndlela yokugcina idatha inciphisa ngandlela-thile umthamo we-HDD (njengoba izikhala ezanele kufanele zigcinwe phakathi kwezindawo ukuze kuvinjelwe ukubhala ngaphezulu kwamathrekhi avela emaqenjini angomakhelwane), lokhu kungasheshisa kakhulu inqubo yokubuyekeza idatha, njengoba manje sekunenani elilinganiselwe kuphela lamathrekhi. iqhaza kukho.
Ukuqoshwa kukazibuthe okufakwe amathayili kuhilela izinketho ezimbalwa zokuqalisa:
- Drive Managed SMR (Drive Managed SMR)
Inzuzo yayo eyinhloko ukuthi asikho isidingo sokushintsha isofthiwe kanye/noma i-hardware yomsingathi, njengoba isilawuli se-HDD sithatha ukulawula inqubo yokurekhoda idatha. Amadrayivu anjalo angaxhunywa kunoma iyiphi isistimu ene-interface edingekayo (i-SATA noma i-SAS), ngemva kwalokho idrayivu izobe isilungele ukusetshenziswa ngokushesha.
Ububi bale ndlela ukuhlukahluka kokusebenza, okwenza i-Drive Managed SMR ingafaneleki ezinhlelweni zebhizinisi lapho ukusebenza kwesistimu kubalulekile. Kodwa-ke, lawo madiski enza kahle ezimeni ezivumela isikhathi esanele sokuthi ukuhlukaniswa kwedatha yasemuva kuqedwe. Ngakho-ke, isibonelo, amadrayivu e-DMSMR Ilungiselelwe ukusetshenziswa ku-8-bay NAS encane, iyinketho enhle kakhulu yokugcinwa kwengobo yomlando noma isistimu yokwenza isipele edinga ukugcinwa kwekhophi yasenqolobaneni yesikhathi eside.
- I-SMR Ephethwe Umsingathi (I-SMR Ephethwe Umsingathi)
I-Host Managed SMR iwukusetshenziswa kwethayela okuncanyelwayo kakhulu ekusetshenzisweni kwebhizinisi. Kulesi simo, uhlelo lokusingatha ngokwalo lunesibopho sokuphatha ukugeleza kwedatha kanye nokufunda / ukubhala imisebenzi, kusetshenziswa lezi zinhloso izandiso ze-ATA (Zoned Device ATA Command Set, ZAC) kanye ne-SCSI (Zoned Block Commands, ZBC) ezithuthukiswe ngu. amakomiti e-INCITS T10 kanye ne-T13.
Uma usebenzisa i-HMSMR, wonke umthamo wesitoreji otholakalayo uhlukaniswa ngezinhlobo ezimbili zezindawo: Izindawo Ezivamile (izindawo ezivamile), ezisetshenziselwa ukugcina imethadatha nokuqoshwa okungenangqondo (empeleni, kudlala indima yenqolobane), kanye Nezindawo Ezidingekayo Zokubhala Okulandelanayo. (izindawo zokubhala ezilandelanayo), ezithatha ingxenye enkulu yenani eliphelele le-hard disk, lapho idatha irekhodwa ngokuqinile ngokulandelana. Idatha engahlelekile igcinwa endaweni yenqolobane, ukusuka lapho ingadluliselwa endaweni ehambisanayo yokubhala elandelanayo. Ngenxa yalokhu, yonke imikhakha yezemvelo ibhalwa ngokulandelana ngokulandelana kwe-radial futhi ibhalwa ngaphezulu kuphela ngemuva kokugoqa, okukuvumela ukuthi uzuze ukusebenza kwesistimu okuzinzile nokubikezelwa. Ngesikhathi esifanayo, amadrayivu e-HMSMR asekela imiyalo yokufunda okungahleliwe ngendlela efanayo namadrayivu asebenzisa i-PMR evamile.
I-SMR Elawulwa Umsingathi isetshenziswa kumadrayivu aqinile ekilasi lebhizinisi .
Ulayini uhlanganisa amadrayivu e-SATA aphezulu kanye ne-SAS aklanyelwe ukusetshenziswa ezikhungweni zedatha ye-hyperscale. Ukusekela i-Host Managed SMR kwandisa kakhulu ububanzi bama-hard drive anjalo: ngaphezu kwezinhlelo zokusekelayo, alungele ukugcinwa kwamafu, i-CDN noma izinkundla zokusakaza. Umthamo omkhulu wama-hard drives ikuvumela ukuthi ukhuphule ngokuphawulekayo ukuminyana kwesitoreji (kuma-rack afanayo) ngezindleko zokuthuthukisa ezincane, kanye nokusetshenziswa kwamandla okuphansi (ngaphansi kwama-watts angu-0,29 ngeterabhayithi yolwazi olugciniwe) kanye nokuchithwa kokushisa (ngokwesilinganiso esingu-5 Β° C esiphansi kune ama-analogues) β kunciphisa nakakhulu izindleko zokusebenza zokugcina isikhungo sedatha.
Okuwukuphela kokubi kwe-HMSMR ubunkimbinkimbi bokuqhathanisa bokuqaliswa. Into ewukuthi namuhla alukho uhlelo lokusebenza olulodwa noma uhlelo lokusebenza olungasebenza namadrayivu anjalo ngaphandle kwebhokisi, yingakho izinguquko ezinkulu ku-stack yesofthiwe zidingeka ukuze kulungiswe ingqalasizinda ye-IT. Okokuqala, lokhu kukhathazeka, yiqiniso, i-OS ngokwayo, okuyinto ezimweni zezikhungo zedatha zanamuhla zisebenzisa amaseva amaningi-core kanye nama-multi-socket kuwumsebenzi ongeyona into encane. Ungafunda kabanzi mayelana nezinketho zokuqalisa ukusekela kwe-Host Managed SMR kusisetshenziswa esikhethekile. okunikezelwe ezindabeni zokugcinwa kwedatha yendawo. Ulwazi oluqoqwe lapha luzokusiza ukuthi uhlole kusengaphambili ukulungela kwengqalasizinda yakho ye-IT ukuze ushintshele kumasistimu okugcina aklanyiwe.
- I-Host Aware SMR (i-SMR isekelwa umsingathi)
I-Host Aware enikwe amandla i-SMR yamadivayisi ahlanganisa ukusebenziseka nokuvumelana nezimo kwe-Drive Managed SMR nesivinini sokurekhoda esisheshayo se-Host Managed SMR. Amadrayivu anjalo abuyela emuva ahambisana nezinhlelo zokugcina zefa futhi angasebenza ngaphandle kokulawula okuqondile okuvela kumsingathi, kodwa kulesi simo, njengamadrayivu e-DMSMR, ukusebenza kwawo kuba okungalindelekile.
Njenge-SMR Ephethwe Umsingathi, I-Host Aware SMR isebenzisa izinhlobo ezimbili zezindawo: Izindawo Ezivamile zokubhala okungahleliwe kanye Nezindawo Ezithandwayo Zokubhala Ezilandelanayo (izindawo ezincanyelwayo zokurekhoda okulandelanayo). Lokhu kokugcina, ngokungafani Nezindawo Ezidingekayo Zokubhala Okulandelanayo okukhulunywe ngenhla, zidluliselwa ngokuzenzakalelayo esigabeni salezo ezijwayelekile uma ziqala ukubhala idatha ngendlela engahlelekile.
Ukuqaliswa kokuqaphela umsingathi kwe-SMR kunikeza izindlela zangaphakathi zokuthola kabusha ekubhaleni okungahambisani. Idatha engahleliwe ibhalwa endaweni yenqolobane, lapho idiski ingadlulisela khona ulwazi endaweni yokubhala elandelanayo ngemva kokuba wonke amabhulokhi adingekayo atholiwe. Idrayivu isebenzisa ithebula le-indirection ukuze ilawule ukubhala kwe-inorder kanye nokuhlukaniswa kwengemuva. Kodwa-ke, uma ukusebenza okubikezelwayo nokuthuthukisiwe kuyadingeka kuzinhlelo zokusebenza zebhizinisi, lokhu kusengafinyelelwa kuphela uma umsingathi ethatha ukulawula okuphelele kwakho konke ukugeleza kwedatha nezindawo zokubhala.
Source: www.habr.com