RAID algorithms yakaunzwa kune veruzhinji kumashure muna 1987. Kusvikira nhasi, ivo vanoramba vari iyo inonyanya kufarirwa tekinoroji yekudzivirira uye kukurumidza kuwana data mumunda wekuchengetedza ruzivo. Asi zera reIT tekinoroji, iyo yakayambuka chiratidzo chemakore makumi matatu, haisi kukura, asi yatochembera. Chikonzero kufambira mberi, izvo zvisingaite zvinounza mikana mitsva. Panguva apo pakanga pasina mamwe madhiraivha kunze kweHDDs, RAID algorithms yakaita kuti zvikwanise kushandisa zvakanyanya kushandiswa kwezviwanikwa zvekuchengetedza. Nekudaro, nekuuya kweSSD, mamiriro achinja zvakanyanya. Iye zvino RAID kana uchishanda neakasimba-state madhiraivha yatove "noose" pakuita kwavo. Naizvozvo, kuvhura iyo yakazara kugona kweSSD yekumhanyisa maitiro, nzira yakasiyana zvachose yekushanda navo inongodiwa.
Pamusoro pemisiyano iri pachena pakati peHDD neSSD mumitemo yekushandisa, idzi mhando dzemidhiya dzine chimwe chinhu chakakosha hunhu: chero hard drive inogona kunyora chero data negranularity yeimwe block (mazuva ano iyi inowanzo 4KB). Kune maSSD, maitiro ekunyorazve inzira yakaoma kwazvo:
- Iyo data yakashandurwa inokopwa kunzvimbo itsva. Muchiitiko ichi, granularity ibhuroko rimwe chete, asi rine mapeji akati wandei uye rine saizi ye256KB - 4MB. Avo. pakuchinja iyo 4KB yakafanana, zvinodikanwa kukopa, pakati pezvimwe zvinhu, ese ari padyo mapeji anoumba imwechete block.
- Maka "chekare" zvivharo sezvisina kushandiswa, kuitira kuti zvigozodzimwa neMutakuri wemarara.
Sequential kunyora / wedzera kune SSD
Panyaya yekutevedzana kunyora / kunyorazve, ichi chimiro cheSSD hachiite basa rakakura maererano nekuita kwayo, nekuti. mabhururu ari padyo, uye anonhonga marara anoita basa rawo zvakanaka kumashure. Asi muhupenyu chaihwo, uye zvakatonyanya muchikamu cheBhizinesi, kuwana zvisina tsarukano kune data kunonyanya kushandiswa kune SSD. Uye iyi data inonyorerwa kunzvimbo dzisina kujairika pamadhiraivha.
Iyo data yakawanda inonyorerwa kuSSD, zvakanyanya kuoma kuti muunganidzi wemarara ashande, sezvo kupatsanurwa kunowedzera zvakanyanya. Nekuda kweizvozvo, nguva inouya apo maitiro ekuchenesa dhiraivha anorega kuve "kumashure": kuita kweSSD kunodonha zvakanyanya, nekuti. chikamu chakakosha chayo chinotorwa neGarbage Collector.
Nzvimbo chaiyo yedata paSSD panguva yekushandiswa kwemazuva ese
Kuenzanisira mashandiro ebasa remuunganidzi wemarara, zvichienderana neyekurekodha modhi padhiraivha, unogona kuita iyo yakapusa bvunzo: inoteedzana uye yakasarudzika kunyora mu4KB inovhara pane 100GB drive. (Kwakabva - kambani )
Sequential Nyora Kuita
Random write performance
Sezvinoonekwa kubva mukuyedzwa, kudonha kwekuita kunogona kusvika kanopfuura kaviri. Uye iyi ingori imwe drive. Paunenge uchishandisa SSD sechikamu cheboka reRAID, nhamba yemabasa ekunyorazve inowedzera zvakanyanya nekuda kwekushanda pamwe chete.
Kazhinji, nekuda kweaya maficha eSSD oparesheni, kune yakadaro parameter kwavari sekunyora amplification. Iyi ndiyo chiyero chehuwandu hwe data yakanyorwa kune dhiraivha kune huwandu hwe data iyo muiti akatumira chaizvo. Uye kune inonyanya kufarirwa RAID5 iyi coefficient ndeye ~ 3.5.
Nekuda kweizvozvo, masisitimu ane classic RAID anonyanya kushandisa SSDs chete ~ 10% yekumhanya kwavo chaiko uye kushata mukuita kana huwandu hwemadhiraivha hunowedzera kusvika kune gumi nemaviri.
Isu tinocherekedzawo kuti kuita kwekunyora kwakanyanya hakungodzikisi kuita kweSSD, asi zvakare kunoderedza kure kure nekusingaperi sosi, nekudaro kupfupisa hupenyu hwebasa rekutyaira.
, inova musimboti wezvese zvigadzirwa zveAccelStor, zvakanyatsogadzirwa seimwe nzira yekirasi RAID algorithms kana uchishanda neSSD. Iko hunyanzvi hwetekinoroji inocherechedzwa neakasiyana patents uye mibairo (kusanganisira paFlash Memory Summit 2016), uye nemhedzisiro yekuzvimiririra bvunzo (semuenzaniso, SPC1).
Essence inosanganisira kushandura zvese zvinopinda zvikumbiro zvekunyora, kunyanya zvemhando isina kurongeka, kuita seti yezvivharo zvakafanana sezvinobvira kune inoteedzana kunyora modhi kubva pakuona kwekutyaira. Nekuda kweizvozvo, kurekodha kuSSD kunoitika mune yakanyanya kugadzikana modhi kwavari, uye mhedzisiro inodarika chero system ine classic RAID.
Ese maSSD muAccelStor masisitimu akakamurwa kuita maviri symmetrical FlexiRemap® mapoka. Saizi yeboka inoenderana nemuenzaniso uye inotangira kubva pa5-11 madhiraivha. Nekutadza kushivirira mukati meboka, parity inoshandiswa yakafanana neRAID5. Mapoka ese ari maviri anoshandiswa pamwechete kugadzira nzvimbo yekuchengetera yakafanana. Naizvozvo, mhedzisiro yekutadza kushivirira ichave yakafanana neRAID50 array ine mapoka maviri: iyo sisitimu inogona kumira kutadza kweanosvika maviri SSD, asi isingapfuure imwe muboka rega rega reFlexiRemap®.
Zvese zvinopinda zvikumbiro zvekunyora zvakakamurwa kuita 4KB zvidhinha, izvo zvakanyorwa muround robin modhi kune ese ari maviri FlexiRemap® mapoka. Panguva imwecheteyo, iyo sisitimu inogara ichichengeta kudiwa kwezvivharo zvakarekodhwa, ichiedza kurekodha mabhuroki akafanana ari padyo kune mumwe nemumwe sezvinobvira kana achinja. Iyo inoshanduka kuva inofananidzira analogue yekugovana, kana inoratidzwa maererano nekuchengetedza masisitimu. Muchiitiko ichi, basa remuunganidzi wemarara rinoshandiswa zvakanyanya: mushure mezvose, zvidhinha zvisina kushandiswa zvichagara zviri pedyo.
Izvo zvinofanirwa kucherechedzwa kuti Kusiyana nezvigadzirwa zvevakwikwidzi, ivo havashandise mashandiro ecaching zvikumbiro zvinouya mu controller's RAM. Ese anouya mabhuroki edata anobva anyorerwa kuSSD. Iyo saiti inogamuchira simbiso yekubudirira kurekodha chete mushure mekunge data yaiswa mumuviri pamadhiraivha. RAM inongochengetera matafura ekuiswa paSSD kuti ikurumidze kupinda uye kuona pekunyora bhuroka rinotevera re data. Zvechokwadi, nokuda kwekuvimbika, makopi ematafura aya anowanikwa pane vezvenhau pachavo. Somugumisiro, maitiro eAccelStor haadi chero kuchengetedzwa kwecheche mumhando yebheteri / capacitor (zvisinei, kukwanisa kutaurirana neUPS kunowanikwa kune "soft" kuvharwa kana pane dambudziko remagetsi).
Kutenda kune iyi nzira yekuronga kurekodha, muunganidzi wemarara anokwanisa kushanda ari kumashure asingakanganisi zvakanyanya kumhanya kwemadhiraivha, izvo zvinozobvumira kusvika 90% yeSSD performance kuti ishandiswe mukati meiyo system. Ichi ndicho chaicho chikonzero chemazinga eIOPS akakwira muAccelStor masisitimu akaenzaniswa neAll Flash, ayo anobva paRAID algorithms.
Chimwe chinhu chakakosha cheFlexiRemap® tekinoroji ndiko kudzikisira kwakakosha kwekunyorera kune SSDs. Nokudaro, iyo yekunyora amplification factor yeAccelStor systems ndeye 1.3 chete, iyo, yakashandurirwa mumutauro wakajairika, inoreva kuwedzera kwehupenyu hwebasa hwemadhiraivha kana ichienzaniswa neRAID5 nekanopfuura ka2.5!
Nekuda kweiyo sisitimu inogara ichitarisisa iyo data yekuisa mutemo pane SSDs, madhiraivha ese anopera zvakaenzana. Iyi nzira inokubvumira kufanotaura hupenyu hwavo hwebasa uye kutumira chiratidzo kune maneja nguva isati yasvika pamusoro pekuneta kwechinyorwa chekurekodha.
Zviri pachena kuti SSDs inogona kukundikana. Muchiitiko ichi, iyo sisitimu ichabva yatanga kuvakazve kune imwe inopisa spare disks. Izvi zvinoita kuti boka reFlexiRemap® riri munzvimbo yakaderedzwa rive rekuverenga-chete, uye zvikumbiro zvese zvekunyora zvinotungamirwa kuboka rechipiri. Iyi nzira yekudzivirira inopihwa kuti ikurumidze kuvakazve kushanda uye kuderedza mukana wekutadza kweimwe dhiraivha mukati meboka rimwe chete. Haisi chakavanzika kuti panguva yekuvakazve, madhiraivha ese ari muboka akawedzera mutoro nekuda kwekukanganiswa kubva pakuverenga, kunyora, uye kudzoreredza mashandiro pane inopisa spare. Izvi zvinowedzera mukana weimwe dhisiki kutadza. Uye iyo yakawanda yekunyora mashandiro, iyo nguva yekuvakazve inotora.
Kana maitiro ekugadzirisa apera uye boka reFlexiRemap® radzokera kune zvakajairika, pachave nekadiki skew mukunyora sosi pakati pemapoka maviri aya. Nokudaro, kuti ienderane nayo, zvinotevera zvinyorwa zvinyorwa zvinowanzowira paboka rakadzorerwa (zvechokwadi, nenzira iyo iyo yekupedzisira hurongwa hunoita haisi kutambura zvakanyanya).
Hazvigoneke kuwedzera mashandiro eAll Flash masisitimu zvichienderana neRAID algorithms pamusoro pehumwe hunhu (~ 280K IOPS@4K nyora zvisina tsarukano) kunyangwe uchishandisa yakaoma caching masisitimu. FlexiRemap® tekinoroji, nekuda kwenzira yakasiyana zvachose yekuronga nzvimbo yekuchengetera, kwete kungokunda nyore chipingamupinyi ichi, asiwo panguva imwe cheteyo inowedzera hupenyu hwesevhisi hweSSD kakawanda. Saka masystem vane mabhenefiti akakomba pakati peEse Flash arrays pamativi mazhinji (IOPS/$, GB/$, TCO, ROI), ichivaita vamiriri vakanaka vezvinzvimbo zvakakosha munzvimbo dzedhata dzevatengi dzekugadzirisa mabasa ane simba rekushandisa.
Source: www.habr.com
