Linux 6.2 tuuma introduseerib Btrfsi parendusi, mis k\u00e4sitlevad RAID 5\/6 \u00abwrite hole\u00bb probleemi parandamist. Probleemi olemus seisneb selles, et kui kriitiline rike toimub kirjutamise k\u00e4igus, ei ole algselt v\u00f5imalik m\u00f5ista, milline plokk on m\u00f5nel RAID-seadmest korrektselt salvestatud ja milline kirjutamine ei ole l\u00f5petatud. Kui on proovida RAID-i taastada sarnases olukorras, v\u00f5ivad plokkide h\u00e4vitamised toimuda, seoses mitteloodud plokkidega, kuna RAID-i plokkide olek on des\u00fcnkroniseeritud. See probleem ilmneb k\u00f5ikides RAID1\/5\/6 massiivides, kus ei ole rakendatud spetsiaalseid meetmeid sellise efekti v\u00e4ltimiseks. <\/p>\n
RAID rakendustes, nagu RAID1 btrfs-is, lahendatakse see probleem kontrollsumma kasutamisega m\u00f5lemas koopias: kui kontrollsummad ei kattu, taastatakse andmed lihtsalt teisest koopiast. See l\u00e4henemine t\u00f6\u00f6tab ka siis, kui m\u00f5ni seade hakkab andma valeandmeid t\u00e4ieliku rikke asemel. <\/p>\n
Kuid RAID5\/6 puhul ei s\u00e4ilita failis\u00fcsteem pariteetplokkide jaoks kontrollsummasid: normaalsetes olukordades kontrollitakse plokkide \u00f5igsust selle fakti p\u00f5hjal, et k\u00f5ik on varustatud kontrollsummaga ja pariteetplokk on v\u00f5imalik andmete p\u00f5hjal taastada. Kuid osalise kirjutamise korral v\u00f5ib see l\u00e4henemine teatud olukordades mitte t\u00f6\u00f6tada. Sellisel juhul, RAID massiivi taastamisel ei ole v\u00e4listatud, et osaliselt kirjutatud plokkide taastamine toimub valesti. <\/p>\n
Btrfs puhul on see probleem eriti oluline, kui kirjutatav andmemahu suurus on v\u00e4iksem kui striip. Sel juhul peab failis\u00fcsteem sooritama lugemise-muudatuste-kirjutamise operatsiooni (read-modify-write, RMW). Kui selle k\u00e4igus satub tegemist katkiste kirjutamistega, v\u00f5ib RMW operatsioon p\u00f5hjustada kahjustusi, mis j\u00e4\u00e4vad avastamata vaatamata kontrollsummadele. Arendajad on teinud muudatusi, kus RMW operatsioon kontrollib blokisid enne selle operatsiooni tegemist, ja vajaduse korral teostab kontrollsummade kontrolli ka p\u00e4rast kirjutamist. Kahjuks toob katkise striibi (RMW) kirjutamise olukord kaasa t\u00e4iendavaid kulusid kontrollsummade arvutamisel, kuid samas suurendab oluliselt usaldusv\u00e4\u00e4rsust. RAID6 puhul ei ole selline loogika veel valmis, kuid selleks, et RAID6-s esineks selline rike, peab kirjutamine eba\u00f5nnestuma korraga kahe seadme peale, mis on v\u00e4hem t\u00f5en\u00e4oline. <\/p>\n
Lisaks v\u00f5ib m\u00e4rkida arendajatelt soovitusi RAID5\/6 kasutamiseks, mille sisuks on see, et Btrfis v\u00f5ivad metaandmete ja andmete salvestamise profiilid erineda. Sellega v\u00f5ib kasutada RAID1 (peegeldus) v\u00f5i isegi RAID1C3 (3 koopiat) metaandmete jaoks, samas kui andmete jaoks kasutatakse RAID5 v\u00f5i RAID6. See tagab usaldusv\u00e4\u00e4rse metaandmete kaitse ja \u00abwrite hole\u00bb puudumise \u00fchelt poolt, ning efektiivse ruumi kasutamise, iseloomuliku RAID5\/6 jaoks, teiselt poolt. See v\u00f5imaldab v\u00e4ltida metaandmete h\u00e4vitamist, samas kui andmete kahjustusi saab parandada. <\/p>\n
Samuti v\u00f5ib m\u00e4rkida, et SSD-de jaoks aktiveeritakse Btrfis versioonis 6.2 vaikimisi as\u00fcnkroonne \u00abdiscard\u00bb operatsiooni k\u00e4itamine (vabade plokkide m\u00e4rkimine, mida ei ole enam f\u00fc\u00fcsiliselt vaja hoida). Selle re\u017eiimi eeliseks on k\u00f5rge j\u00f5udlus, kuna \u00abdiscard\u00bb operatsioonide t\u00f5hus r\u00fchmitamine j\u00e4rjekorda ja seej\u00e4rel j\u00e4rjekorra t\u00f6\u00f6tlemine taustaprotsessoriga, mis t\u00f5ttu ei aeglusta tavalised failis\u00fcsteemi operatsioonid, nagu s\u00fcnkrone \u00abdiscard\u00bb plokkide vabastamise ajal, ning SSD suudab teha paremaid otsuseid. Teiselt poolt ei ole enam vajalik kasutada fstrim-t\u00fc\u00fcpi utiliite, kuna k\u00f5ik saadaval olevad plokid puhastatakse failis\u00fcsteemis ilma t\u00e4iendava skanneerimise vajaduseta ja ilma operatsioonide aeglustamiseta. \u0414\u043b\u044f \u0432\u043a\u043b\u044e\u0447\u0435\u043d\u0438\u044f \u044f\u0434\u0440\u043e Linux 6.2 \u043f\u0440\u0435\u0434\u043b\u043e\u0436\u0435\u043d\u044b \u0443\u043b\u0443\u0447\u0448\u0435\u043d\u0438\u044f Btrfs, \u043a\u0430\u0441\u0430\u044e\u0449\u0438\u0435\u0441\u044f \u0438\u0441\u043f\u0440\u0430\u0432\u043b\u0435\u043d\u0438\u044f \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u044b «write hole» \u0432 \u0440\u0435\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u0438 RAID 5\/6. \u0421\u0443\u0442\u044c \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u044b \u0441\u0432\u043e\u0434\u0438\u0442\u0441\u044f \u043a \u0442\u043e\u043c\u0443, \u0447\u0442\u043e \u0435\u0441\u043b\u0438 \u043a\u0440\u0430\u0445 \u0441\u043b\u0443\u0447\u0438\u043b\u0441\u044f \u0432\u043e \u0432\u0440\u0435\u043c\u044f \u0437\u0430\u043f\u0438\u0441\u0438, \u0438\u0437\u043d\u0430\u0447\u0430\u043b\u044c\u043d\u043e \u043d\u0435\u0432\u043e\u0437\u043c\u043e\u0436\u043d\u043e \u043f\u043e\u043d\u044f\u0442\u044c \u043a\u0430\u043a\u043e\u0439 \u0431\u043b\u043e\u043a \u043d\u0430 \u043a\u0430\u043a\u043e\u043c \u0438\u0437 \u0443\u0441\u0442\u0440\u043e\u0439\u0441\u0442\u0432 RAID \u0437\u0430\u043f\u0438\u0441\u0430\u043b\u0441\u044f \u043a\u043e\u0440\u0440\u0435\u043a\u0442\u043d\u043e, \u0430 \u0432 \u043a\u0430\u043a\u043e\u043c \u0437\u0430\u043f\u0438\u0441\u044c \u043d\u0435 \u0431\u044b\u043b\u0430 \u0437\u0430\u0432\u0435\u0440\u0448\u0435\u043d\u0430. \u0412 \u0441\u043b\u0443\u0447\u0430\u0435 \u043f\u043e\u043f\u044b\u0442\u043a\u0438 \u0432\u043e\u0441\u0441\u0442\u0430\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f RAID \u0432 \u043f\u043e\u0434\u043e\u0431\u043d\u043e\u0439 […]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[702],"tags":[],"class_list":["post-106149","post","type-post","status-publish","format-standard","hentry","category-news"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\n","aioseo_head_json":{"title":"\ud83e\udd47Linux 6.2 tuumisse lisanduvad RAID5\/6 parendused Btrfs'is | ProHoster","description":"Linux 6.2 tuumises on Btrfs parendused, mis k\u00e4sitlevad RAID 5\/6 teostuse \"write hole\" probleemi lahendamist.","canonical_url":"https:\/\/prohoster.info\/et\/blog\/news\/v-yadro-linux-6-2-vojdut-uluchsheniya-raid5-6-v-btrfs","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"et_EE","og:site_name":"ProHoster | \u041a\u0443\u043f\u0438\u0442\u044c \u043d\u0430\u0434\u0435\u0436\u043d\u044b\u0439 \u0445\u043e\u0441\u0442\u0438\u043d\u0433 \u0434\u043b\u044f \u0441\u0430\u0439\u0442\u043e\u0432 \u0441 \u0437\u0430\u0449\u0438\u0442\u043e\u0439 \u043e\u0442 DDoS, VPS VDS \u0441\u0435\u0440\u0432\u0435\u0440\u044b","og:type":"article","og:title":"\ud83e\udd47\u0412 \u044f\u0434\u0440\u043e Linux 6.2 \u0432\u043e\u0439\u0434\u0443\u0442 \u0443\u043b\u0443\u0447\u0448\u0435\u043d\u0438\u044f RAID5\/6 \u0432 Btrfs | ProHoster","og:description":"\u0414\u043b\u044f \u0432\u043a\u043b\u044e\u0447\u0435\u043d\u0438\u044f \u044f\u0434\u0440\u043e Linux 6.2 \u043f\u0440\u0435\u0434\u043b\u043e\u0436\u0435\u043d\u044b \u0443\u043b\u0443\u0447\u0448\u0435\u043d\u0438\u044f Btrfs, \u043a\u0430\u0441\u0430\u044e\u0449\u0438\u0435\u0441\u044f \u0438\u0441\u043f\u0440\u0430\u0432\u043b\u0435\u043d\u0438\u044f \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u044b "write hole" \u0432 \u0440\u0435\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u0438 RAID 5\/6.","og:url":"https:\/\/prohoster.info\/et\/blog\/news\/v-yadro-linux-6-2-vojdut-uluchsheniya-raid5-6-v-btrfs","og:image":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:secure_url":"https:\/\/prohoster.info\/wp-content\/uploads\/2021\/11\/logo-350.jpg","og:image:width":350,"og:image:height":350,"article:published_time":"2022-12-18T19:36:39+00:00","article:modified_time":"2022-12-18T19:36:39+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":[],"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/posts\/106149","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/comments?post=106149"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/posts\/106149\/revisions"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/media?parent=106149"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/categories?post=106149"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/tags?post=106149"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n
Allikas: opennet.ru<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"