Nkhaniyi inalembedwa kuti ikuthandizeni kusankha yankho loyenera nokha ndikumvetsetsa kusiyana pakati pa SDS monga Gluster, Ceph ndi Vstorage (Virtuozzo).
Zolembazo zimagwiritsa ntchito maulalo azolemba ndikuwulula mwatsatanetsatane zovuta zina, kotero mafotokozedwewo azikhala achidule momwe angathere, pogwiritsa ntchito mfundo zazikulu popanda fluff zosafunikira komanso chidziwitso choyambira chomwe mungathe, ngati mukufuna, kupeza pa intaneti.
M'malo mwake, mitu yomwe yatulutsidwa imafuna matani a mawuwo, koma m'dziko lamakono anthu ambiri sakonda kuwerenga zambiri))), kotero mutha kuwerenga mwachangu ndikupanga chisankho, ndipo ngati pali china chake. osamveka bwino, tsatirani maulalo kapena mawu osamveka bwino a google))), ndipo nkhaniyi ili ngati chotchingira chowonekera pamitu yakuzama iyi, kuwonetsa kudzazidwa - mfundo zazikuluzikulu za chisankho chilichonse.
gluster
Tiyeni tiyambe ndi Gluster, yomwe imagwiritsidwa ntchito mwakhama ndi opanga ma hyperconverged platforms omwe ali ndi SDS pogwiritsa ntchito gwero lotseguka la malo enieni ndipo angapezeke pa webusaiti ya RedHat mu gawo losungirako, komwe mungasankhe kuchokera ku zosankha ziwiri za SDS: Gluster kapena Ceph.
Gluster imakhala ndi omasulira ambiri - ntchito zomwe zimagwira ntchito yonse yogawa mafayilo, ndi zina. Njerwa ndi ntchito yomwe imathandiza disk imodzi, Volume ndi voliyumu (dziwe) lomwe limagwirizanitsa njerwa izi. Kenako pamabwera ntchito yogawa mafayilo m'magulu pogwiritsa ntchito ntchito ya DHT (yogawa hash table). Sitingaphatikizepo ntchito ya Sharding pofotokozera chifukwa maulalo omwe ali pansipa afotokoza zovuta zomwe zikugwirizana nazo.
Polemba, fayilo yonseyo imasungidwa mu njerwa ndipo kopi yake imalembedwa nthawi imodzi ndi njerwa pa seva yachiwiri. Kenaka, fayilo yachiwiri idzalembedwera ku gulu lachiwiri la njerwa ziwiri (kapena zambiri) pamaseva osiyanasiyana.
Ngati mafayilo ali ofanana kukula kwake ndipo voliyumu ili ndi gulu limodzi lokha, ndiye kuti zonse zili bwino, koma pazifukwa zina mavuto otsatirawa adzabwera kuchokera kukufotokozera:
- malo m'magulu amagwiritsidwa ntchito mosagwirizana, zimatengera kukula kwa mafayilo ndipo ngati palibe malo okwanira pagulu kuti alembe fayilo, mudzalandira cholakwika, fayiloyo sidzalembedwa ndipo sidzagawidwanso ku gulu lina. ;
- polemba fayilo imodzi, IO imapita ku gulu limodzi lokha, ena onse ndi opanda pake;
- simungapeze IO ya voliyumu yonse polemba fayilo imodzi;
- ndipo lingaliro lachidziwitso likuwoneka lopanda phindu chifukwa cha kusowa kwa kugawa kwa deta mu midadada, komwe kumakhala kosavuta kulinganiza ndi kuthetsa vuto la kugawa yunifolomu, ndipo osati monga tsopano fayilo yonse imalowa mu chipika.
Kuchokera kumafotokozedwe ovomerezeka Timazindikiranso kuti gluster imagwira ntchito ngati kusungira mafayilo pamwamba pa zida zapamwamba za RAID. Pakhala pali zoyesayesa zachitukuko zodula (Sharding) mafayilo kukhala midadada, koma zonsezi ndizowonjezera zomwe zimapangitsa kutayika kwa magwiridwe antchito panjira yomanga yomwe ilipo kale, kuphatikiza kugwiritsa ntchito zida zogawira mwaufulu zomwe zili ndi malire a magwiridwe antchito monga Fuse. Palibe mautumiki a metadata, omwe amachepetsa magwiridwe antchito ndi kuthekera kolekerera kosungirako pogawira mafayilo mu midadada. Zizindikiro zogwira ntchito bwino zimatha kuwonedwa ndi kasinthidwe ka "Distributed Replicated" ndipo chiwerengero cha node chiyenera kukhala osachepera 6 kuti apange choyimira chodalirika cha 3 ndi kugawa katundu wokwanira.
Zomwe zapezazi zikugwirizananso ndi kufotokozera kwa wogwiritsa ntchito ndi poyerekezera ndi , ndipo palinso kufotokoza kwa zochitika zomwe zimatsogolera kumvetsetsa kwa kasinthidwe kopindulitsa komanso kodalirika
Chithunzichi chikuwonetsa kugawa kwa katundu polemba mafayilo awiri, pomwe makope a fayilo yoyamba amagawidwa pamaseva atatu oyamba, omwe amaphatikizidwa mugulu la 0, ndipo makope atatu a fayilo yachiwiri amayikidwa pagulu lachiwiri voliyumu1 mwa atatu. maseva. Seva iliyonse ili ndi disk imodzi.
Mapeto ake ndikuti mutha kugwiritsa ntchito Gluster, koma ndikumvetsetsa kuti padzakhala zolepheretsa pakugwirira ntchito komanso kulolerana zolakwa zomwe zimabweretsa zovuta pansi pazifukwa zina za yankho la hyperconverged, pomwe zofunikira zimafunikiranso pakuchulukira kwamakompyuta am'malo opezeka.
Palinso zizindikiro zina za Gluster zomwe zingatheke pazochitika zina, zochepa
ceph
Tsopano tiyeni tiwone Ceph kuchokera ku mafotokozedwe a zomangamanga omwe ndidatha Palinso kufananiza pakati , komwe mungamvetsetse nthawi yomweyo kuti ndikofunikira kuyika Ceph pamaseva osiyana, popeza ntchito zake zimafunikira zida zonse za Hardware.
zomangamanga zovuta kwambiri kuposa Gluster ndipo pali mautumiki monga mautumiki a metadata, koma mulu wonse wa zigawo zake ndizovuta kwambiri ndipo sizisinthasintha kwambiri kuti mugwiritse ntchito mu njira yothetsera vutoli. Deta imasungidwa muzitsulo, zomwe zimawoneka zopindulitsa kwambiri, koma mumagulu a mautumiki onse (zigawo), pali zotayika ndi latency pansi pa katundu wina ndi zochitika zadzidzidzi, mwachitsanzo zotsatirazi:
Kuchokera kukufotokozera za zomangamanga, mtima ndi CRUSH, chifukwa malo osungiramo deta amasankhidwa. Kenako pakubwera PG - ichi ndiye chovuta kwambiri (gulu lomveka) kumvetsetsa. Ma PG amafunikira kuti CRUSH ikhale yogwira mtima. Cholinga chachikulu cha PG ndikuyika zinthu m'magulu kuti muchepetse kugwiritsidwa ntchito kwazinthu, kukulitsa magwiridwe antchito komanso scalability. Kulankhula zinthu mwachindunji, payekhapayekha, popanda kuziphatikiza kukhala PG kungakhale kodula kwambiri. OSD ndi ntchito ya disk iliyonse.
Gulu litha kukhala ndi dziwe la data limodzi kapena ambiri pazolinga zosiyanasiyana komanso zosintha zosiyanasiyana. Maiwe amagawidwa m'magulu oyika. Magulu oyika amasunga zinthu zomwe makasitomala amapeza. Apa ndipamene mlingo womveka umathera, ndipo msinkhu wa thupi umayamba, chifukwa gulu lirilonse loyika limapatsidwa diski imodzi yaikulu ndi ma disks angapo ofananitsa (ndi angati omwe amadalira dziwe lobwerezabwereza). Mwa kuyankhula kwina, pamlingo womveka chinthucho chimasungidwa mu gulu linalake lokhazikitsidwa, komanso pamtunda wa thupi - pa disks zomwe zimaperekedwa kwa izo. Pachifukwa ichi, ma disks amatha kukhala pamagulu osiyanasiyana kapena m'malo osiyanasiyana.
Muchiwembu ichi, magulu oyikapo amawoneka ngati mulingo wofunikira kuti athe kusinthasintha kwa yankho lonse, koma panthawi imodzimodziyo, ngati cholumikizira chowonjezera mu unyolo uwu, womwe umapereka mwadala kutayika kwa zokolola. Mwachitsanzo, polemba deta, dongosololi liyenera kuligawa m'magulu awa ndiyeno pamlingo wakuthupi kukhala diski yayikulu ndi ma disks a replicas. Ndiko kuti, ntchito ya Hash imagwira ntchito pofufuza ndi kuyika chinthu, koma pali zotsatira zake - ndizovuta kwambiri komanso zoletsa kumanganso hashi (powonjezera kapena kuchotsa disk). Vuto lina la hashi ndi malo okhomeredwa bwino a deta omwe sangasinthidwe. Ndiko kuti, ngati mwanjira ina diski ikuchulukirachulukira, ndiye kuti makinawo alibe mwayi woti asayilembe (posankha diski ina), ntchito ya hashi imakakamiza kuti deta ipezeke molingana ndi lamulo, zivute zitani. disk ndi, kotero Ceph amadya kwambiri kukumbukira pamene akumanganso PG ngati kudzichiritsa kapena kuonjezera yosungirako. Mapeto ake ndikuti Ceph imagwira ntchito bwino (ngakhale pang'onopang'ono), koma pokhapokha ngati palibe makulitsidwe, zochitika zadzidzidzi, kapena zosintha.
Pali, ndithudi, zosankha zowonjezera ntchito kupyolera mu caching ndi cache kugawana, koma izi zimafuna hardware yabwino ndipo padzakhalabe zotayika. Koma chonsecho, Ceph ikuwoneka yoyesa kuposa Gluster pakupanga. Komanso, pogwiritsira ntchito mankhwalawa, m'pofunika kuganizira chinthu chofunika kwambiri - ichi ndi luso lapamwamba, chidziwitso ndi luso lomwe likutsindika kwambiri pa Linux, chifukwa ndikofunika kwambiri kuyika, kukonza ndi kusunga zonse molondola, zomwe zimapatsa udindo wochulukirapo komanso kulemetsa kwa woyang'anira.
Kusungirako
Zomangamanga zimawoneka zosangalatsa kwambiri , yomwe ingagwiritsidwe ntchito pamodzi ndi hypervisor pa mfundo zomwezo, mofanana , koma ndikofunikira kwambiri kukonza zonse moyenera kuti mukwaniritse ntchito yabwino. Ndiko kuti, kutumiza mankhwala otere kuchokera m'bokosi pa kasinthidwe kalikonse popanda kuganizira malingaliro malinga ndi zomangamanga kudzakhala kosavuta, koma kosapindulitsa.
Zomwe zitha kukhalapo kuti zisungidwe pafupi ndi ntchito za kvm-qemu hypervisor, ndipo awa ndi mautumiki ochepa pomwe gawo lokhazikika lazigawo lapezeka: ntchito yamakasitomala imayikidwa kudzera pa FUSE (yosinthidwa, osati gwero lotseguka), ntchito ya metadata ya MDS. (Metadata service), service Chunk data block blocks, yomwe pamlingo wakuthupi ndi yofanana ndi disk imodzi ndipo ndizo zonse. Pankhani ya liwiro, ndiye kuti ndibwino kugwiritsa ntchito chiwembu chololera zolakwika chokhala ndi zofananira ziwiri, koma ngati mugwiritsa ntchito caching ndi logi pa ma drive a SSD, ndiye kuti zolembera zololera zolakwika (kufufutani zolemba kapena raid6) zitha kuchulukidwa bwino pa a. hybrid scheme kapena bwino pa flash iliyonse. Pali zovuta zina ndi EC (kufufuta zolemba): posintha chipika chimodzi cha data, ndikofunikira kuwerengeranso kuchuluka kwa magawo. Kuti alambalale zotayika zomwe zimakhudzidwa ndi ntchitoyi, Ceph amalembera ku EC mochedwerapo ndipo zovuta zogwira ntchito zitha kuchitika panthawi ya pempho linalake, pomwe, mwachitsanzo, midadada yonse iyenera kuwerengedwa, komanso pankhani ya Virtuozzo Storage, kulemba midadada yosinthidwa kumachitika. pogwiritsa ntchito njira ya "log-structured file system", yomwe imachepetsa ndalama zowerengera. Kuyerekeza pafupifupi zosankha ndi kufulumizitsa ntchito ndi popanda EC, pali - ziwerengerozo zikhoza kukhala pafupifupi malingana ndi kulondola kwa coefficient ya wopanga zipangizo, koma zotsatira za mawerengedwe ndi chithandizo chabwino pokonzekera kukonzekera.
Chithunzi chosavuta cha zigawo zosungirako sichikutanthauza kuti zigawozi sizimayamwa koma ngati muwerengera ndalama zonse pasadakhale, mutha kudalira mgwirizano pafupi ndi hypervisor.
Pali chiwembu chofanizira kugwiritsa ntchito zida za Hardware ndi Ceph ndi Virtuozzo yosungirako ntchito.
Ngati poyamba zinali zotheka kuyerekeza Gluster ndi Ceph pogwiritsa ntchito nkhani zakale, pogwiritsa ntchito mizere yofunika kwambiri kuchokera kwa iwo, ndiye kuti ndi Virtuozzo ndizovuta kwambiri. Palibe zolemba zambiri pazogulitsa izi ndipo zambiri zitha kupezeka kuchokera pazolembedwa kupita kapena m'Chirasha ngati tiwona Vstorage ngati malo osungira omwe amagwiritsidwa ntchito mumayankho a hyperconverged m'makampani monga ndi Acronis.
Ndiyesera kuthandizira kufotokozera za zomangamanga izi, kotero padzakhala malemba ochulukirapo, koma zimatengera nthawi yochuluka kuti mumvetsetse zolembazo nokha, ndipo zolemba zomwe zilipo zingagwiritsidwe ntchito ngati zolembera pokonzanso tebulo. za zomwe zili mkati kapena kusaka ndi mawu osakira.
Tiyeni tilingalire zojambulira pamasinthidwe amtundu wosakanizidwa ndi zigawo zomwe zafotokozedwa pamwambapa: kujambula kumayamba kupita kumalo komwe kasitomala adayambitsa (FUSE mount point service), koma gawo la Metadata Service (MDS) litero. wongolerani kasitomala mwachindunji ku ntchito yomwe mukufuna (malo osungira CS midadada), ndiye kuti, MDS sichita nawo ntchito yojambulira, koma imangowongolera ntchitoyo ku chunk yofunikira. Nthawi zambiri, titha kupereka fanizo lojambulira ndikutsanulira madzi mu migolo. Mgolo uliwonse ndi 256MB data block.
Ndiko kuti, diski imodzi ndi chiwerengero cha migolo yotereyi, ndiko kuti, voliyumu ya disk yogawidwa ndi 256MB. Kope lililonse limagawidwa ku mfundo imodzi, yachiwiri pafupifupi yofanana ndi mfundo ina, ndi zina ... chipika ku SSD, ndi kukonzanso kofanana kuchokera ku SSD kudzapitirira pa HDD, ngati kumbuyo. Pankhani ya ma replicas atatu, mbiriyo idzaperekedwa pambuyo potsimikiziridwa kuchokera ku SSD ya node yachitatu. Zitha kuwoneka kuti kuchuluka kwa liwiro lolemba la ma SSD atatu kumatha kugawidwa ndi atatu ndipo tipeza liwiro lolemba la chofananira chimodzi, koma makope amalembedwa mofananira ndipo liwiro la network Latency nthawi zambiri limakhala lalitali kuposa la SSD, ndipo kwenikweni kulemba ntchito kudzadalira maukonde. Pachifukwa ichi, kuti muwone IOPS yeniyeni, muyenera kutsegula Vstorage yonse molondola , ndiko, kuyesa katundu weniweni, osati kukumbukira ndi cache, kumene kuli koyenera kuganizira kukula koyenera kwa chipika cha deta, chiwerengero cha ulusi, ndi zina zotero.
Cholemba chojambulira chomwe chatchulidwa pamwambapa pa SSD chimagwira ntchito kotero kuti data ikangolowamo, imawerengedwa nthawi yomweyo ndi utumiki ndikulembera HDD. Pali mautumiki angapo a metadata (MDS) pagulu lililonse ndipo chiwerengero chawo chimatsimikiziridwa ndi quorum, yomwe imagwira ntchito molingana ndi algorithm ya Paxos. Kuchokera pamalingaliro a kasitomala, malo okwera a FUSE ndi foda yosungiramo masango yomwe imawoneka nthawi imodzi ndi node zonse mumagulu, node iliyonse imakhala ndi kasitomala wokwera molingana ndi mfundo iyi, kotero kusungirako kumapezeka ku node iliyonse.
Kuti mugwire ntchito iliyonse mwa njira zomwe tafotokozazi, ndikofunikira kwambiri, pakukonzekera ndi kutumizira, kukonza maukonde molondola, komwe kudzakhala kulinganiza chifukwa cha kuphatikizika ndikusankhidwa bwino kwa mayendedwe apakompyuta. Pophatikizana, ndikofunikira kusankha njira yoyenera ya hashing ndi makulidwe ake. Palinso kusiyana kwakukulu kwambiri kuchokera ku SDS yomwe yafotokozedwa pamwambapa, iyi ndi fuse ndi teknoloji yofulumira mu Virtuozzo Storage. Zomwe, kuwonjezera pa fusesi yamakono, mosiyana ndi mayankho ena otseguka, imawonjezera kwambiri IOPS ndikukulolani kuti musakhale ndi malire ndi makulitsidwe opingasa kapena ofukula. Kawirikawiri, poyerekeza ndi zomangamanga zomwe zafotokozedwa pamwambapa, izi zikuwoneka zamphamvu kwambiri, koma chifukwa cha zosangalatsa zoterezi, ndithudi, muyenera kugula malayisensi, mosiyana ndi Ceph ndi Gluster.
Kuti tifotokoze mwachidule, titha kuwunikira pamwamba pazitatu: Virtuozzo Storage imatenga malo oyamba malinga ndi magwiridwe antchito komanso kudalirika kwa zomangamanga, Ceph akutenga malo achiwiri, ndipo Gluster akutenga malo achitatu.
Njira zomwe Virtuozzo Storage idasankhidwira: ndi gawo labwino kwambiri lazomangamanga, lamakono panjira ya Fuse iyi ndi njira yachangu, masinthidwe osinthika a hardware, kugwiritsa ntchito zinthu zochepa komanso kuthekera kogawana ndi compute (computing/virtualization), ndiko kuti, ndizoyenera kwathunthu yankho la hyperconverged , lomwe ali gawo lake. Malo achiwiri ndi Ceph chifukwa ndi zomangamanga zopindulitsa kwambiri poyerekeza ndi Gluster, chifukwa cha ntchito yake muzitsulo, komanso zochitika zosinthika komanso kuthekera kugwira ntchito m'magulu akuluakulu.
Pali ndondomeko zolembera kuyerekezera pakati pa vSAN, Space Direct Storage, Vstorage ndi Nutanix Storage, kuyesa Vstorage pa HPE ndi zipangizo za Huawei, komanso zochitika zogwirizanitsa Vstorage ndi machitidwe osungira kunja kwa hardware, kotero ngati mumakonda nkhaniyi, ingakhale zabwino kupeza ndemanga kuchokera kwa inu, zomwe zingapangitse chidwi cha nkhani zatsopano, poganizira ndemanga zanu ndi zofuna zanu.
Source: www.habr.com