stub.go me titujt e funksioneve p\u00ebr lidhjen e dy bot\u00ebve: Go dhe assembler.\n<\/li>\n<\/ul>\n\n
S\u00eb pari, le t\u00eb shohim versionet skalar.
Fatkeq\u00ebsisht, ne nuk mund ta detyrojm\u00eb kompilerin t\u00eb bej inlining funksionet tona t\u00eb shkruara n\u00eb assembler. Deri m\u00eb sot, kompileri Go nuk ka nj\u00eb mund\u00ebsi t\u00eb till\u00eb, megjithat\u00eb k\u00ebrkesa p\u00ebr ta shtuar at\u00eb ka qen\u00eb aktive p\u00ebr nj\u00eb koh\u00eb t\u00eb gjat\u00eb.<\/p>\n
Pik\u00ebrisht p\u00ebr k\u00ebt\u00eb arsye, nuk \u00ebsht\u00eb e mundur t\u00eb marrim ndonj\u00eb p\u00ebrfitim nga funksionet e vogla n\u00eb assembler. Na nevojitet ose t\u00eb shkruajm\u00eb funksione m\u00eb t\u00eb m\u00ebdha, ose t\u00eb p\u00ebrdorim paket\u00ebn e re math\/bits, ose t\u00eb anashkalojm\u00eb assemblerin.<\/p>\n
Tani le t\u00eb shikojm\u00eb versionet vektoriale t\u00eb funksioneve tona.
Inovacioni i dyt\u00eb lidhet me faktin se vendosa t\u00eb p\u00ebrdor nj\u00eb optimizim q\u00eb quhet zvog\u00eblim i ciklit (loop unrolling), dometh\u00ebn\u00eb t\u00eb b\u00ebj tet\u00eb operacione cikli manualisht para se t\u00eb hidhem n\u00eb fillim t\u00eb ciklit. Ky optimizim zvog\u00eblon numrin e branch-eve n\u00eb kod, dhe \u00ebsht\u00eb i kufizuar nga numri i regjistrave t\u00eb lir\u00eb t\u00eb disponuesh\u00ebm.
Problemet e indekseve bitmap<\/h2>\n \nTani q\u00eb ne kemi shqyrtuar implementimin e thjesht\u00eb t\u00eb indeksit bitmap n\u00eb Go dhe nj\u00eb implementim shum\u00eb m\u00eb t\u00eb produktiv n\u00eb assembler, le t\u00eb flasim p\u00ebrfundimisht p\u00ebr at\u00eb se pse indekset bitmap p\u00ebrdoren kaq rrall\u00eb.
Problemi i kardinalitetit t\u00eb lart\u00eb<\/h2>\n \nPra, na thuhet se indekset bitmap i p\u00ebrshtaten vet\u00ebm fushave me kardinalitet t\u00eb vog\u00ebl, q\u00eb do t\u00eb thot\u00eb q\u00eb ato kan\u00eb pak vlera (p.sh., gjinia ose ngjyra e syve), dhe arsyeja \u00ebsht\u00eb se p\u00ebrfaq\u00ebsimi i zakonsh\u00ebm i k\u00ebtyre fushave (nj\u00eb bit p\u00ebr vler\u00eb) n\u00eb rastin e kardinalitetit t\u00eb lart\u00eb do t\u00eb marr\u00eb shum\u00eb hap\u00ebsir\u00eb dhe, m\u00eb shum\u00eb, k\u00ebto indekse bitmap do t\u00eb ishin t\u00eb mbushura pak (rrall\u00eb).
Mund t\u00eb takoni bitmapet roaring n\u00eb aplikacionet m\u00eb t\u00eb njohura. Padyshim, ekziston nj\u00eb sasi e madhe implementimesh p\u00ebr gjuh\u00eb t\u00eb ndryshme programimi, duke p\u00ebrfshir\u00eb m\u00eb shum\u00eb se tre implementime p\u00ebr Go.
Duket se mund t\u00eb grupojm\u00eb vlera t\u00eb ngjashme n\u00eb grupe brenda 1 cm.<\/p>\n
Dhe n\u00ebse gjithashtu e dim\u00eb se ka shum\u00eb pak njer\u00ebz q\u00eb kan\u00eb lart\u00ebsi m\u00eb t\u00eb vog\u00ebl se 50 cm dhe m\u00eb shum\u00eb se 250 cm, at\u00ebher\u00eb ne mund, n\u00eb thelb, ta kthejm\u00eb nj\u00eb fush\u00eb me kardinalitet t\u00eb pafund n\u00eb nj\u00eb fush\u00eb me kardinalitet prej rreth 200 vlerash.<\/p>\n
Sigurisht, n\u00ebse \u00ebsht\u00eb e nevojshme, mund t\u00eb b\u00ebjm\u00eb filtrimin e m\u00ebtejm\u00eb m\u00eb von\u00eb.<\/p>\n
Problemi i kapacitetit t\u00eb lart\u00eb t\u00eb transmetimit<\/h2>\n \nProblemi tjet\u00ebr i indekseve bitmap \u00ebsht\u00eb se p\u00ebrdit\u00ebsimi i tyre mund t\u00eb jet\u00eb shum\u00eb i kushtuesh\u00ebm.<\/p>\n
Baza t\u00eb dh\u00ebnash duhet t\u00eb ofrojn\u00eb mund\u00ebsin\u00eb p\u00ebr t\u00eb p\u00ebrdit\u00ebsuar t\u00eb dh\u00ebnat n\u00eb momentin kur potencialisht qindra k\u00ebrkesa t\u00eb tjera po k\u00ebrkojn\u00eb p\u00ebr k\u00ebto t\u00eb dh\u00ebna. Kemi nevoj\u00eb p\u00ebr lok si p\u00ebr t\u00eb shmangur problemet me qasjen e p\u00ebrbashk\u00ebt n\u00eb t\u00eb dh\u00ebna apo probleme t\u00eb tjera t\u00eb aksesit t\u00eb p\u00ebrbashk\u00ebt. Dhe atje ku ka nj\u00eb lok t\u00eb madh, ka nj\u00eb problem \u2014 kontestimi i lokut, kur ky lok b\u00ebhet ngushtic\u00eb.
Sharding-u \u00ebsht\u00eb nj\u00eb koncept i thjesht\u00eb dhe i njohur. Ju mund t\u00eb b\u00ebni sharding t\u00eb indekseve bitmap ashtu si\u00e7 do t\u00eb b\u00ebni sharding p\u00ebr \u00e7do t\u00eb dh\u00ebnat tjet\u00ebr. N\u00eb vend t\u00eb nj\u00eb loku t\u00eb madh, do t\u00eb merrni shum\u00eb lok\u00eb t\u00eb vegj\u00ebl dhe k\u00ebshtu do t\u00eb eliminoni kontestimin e lokut.<\/p>\n
M\u00ebnyra e dyt\u00eb p\u00ebr t\u00eb zgjidhur problemin \u00ebsht\u00eb p\u00ebrdorimi i indekseve t\u00eb versionuara. Ju mund t\u00eb keni nj\u00eb kopje t\u00eb indeksit q\u00eb e p\u00ebrdorni p\u00ebr t\u00eb k\u00ebrkuar ose lexuar, dhe nj\u00eb tjet\u00ebr p\u00ebr t\u00eb shkruar ose p\u00ebrdit\u00ebsuar. Dhe n\u00eb nj\u00eb interval t\u00eb caktuar kohor (p\u00ebr shembull, \u00e7do 100 ms ose 500 ms) ju i duploni dhe i nd\u00ebrroni vendet. Sigurisht, ky qasje \u00ebsht\u00eb e zbatueshme vet\u00ebm n\u00eb ato raste kur aplikacioni juaj mund t\u00eb punoj\u00eb me nj\u00eb indeks k\u00ebrkimi q\u00eb ka nj\u00eb vones\u00eb t\u00eb vog\u00ebl.<\/p>\n
K\u00ebto dy qasje mund t\u00eb p\u00ebrdoren nj\u00ebkoh\u00ebsisht: ju mund t\u00eb keni nj\u00eb indeks t\u00eb versionuar t\u00eb sharding-uara.<\/p>\n
K\u00ebrkesat m\u00eb t\u00eb nd\u00ebrlikuara<\/h2>\n Problemi i fundit me indekset bitmap \u00ebsht\u00eb se, si\u00e7 na thon\u00eb, ato nuk jan\u00eb shum\u00eb t\u00eb p\u00ebrshtatshme p\u00ebr tipe m\u00eb t\u00eb nd\u00ebrlikuara k\u00ebrkesash, p\u00ebr shembull k\u00ebrkesave \"n\u00eb interval\".<\/p>\n
Dhe n\u00eb t\u00eb v\u00ebrtet\u00eb, n\u00ebse mendojm\u00eb p\u00ebr k\u00ebt\u00eb, operacionet bitore si AND, OR etj. nuk jan\u00eb shum\u00eb t\u00eb p\u00ebrshtatshme p\u00ebr k\u00ebrkesat si \"M\u00eb trego hotellet me \u00e7mime dhome nga 200 n\u00eb 300 dollar\u00eb p\u00ebr nat\u00eb\".
Por problemi, gjithashtu, zgjidhet leht\u00ebsisht duke p\u00ebrdorur nj\u00eb p\u00ebrfaq\u00ebsim t\u00eb krijuar posa\u00e7\u00ebrisht p\u00ebr k\u00ebt\u00eb lloj k\u00ebrkese. N\u00eb punimet shkencore, kjo quhet bitmap me kodim range.
Duke p\u00ebrdorur k\u00ebt\u00eb p\u00ebrfaq\u00ebsim, ne mund t\u00eb p\u00ebrgjigjemi ndaj k\u00ebtij lloji k\u00ebrkese duke kaluar p\u00ebrmes indeksit vet\u00ebm dy her\u00eb. S\u00eb pari, ne do t\u00eb marrim nj\u00eb list\u00eb hotelesh ku \u00e7mimi i dhom\u00ebs \u00ebsht\u00eb m\u00eb pak se 300 dollar\u00eb, e m\u00eb pas do ta heqim at\u00eb nga lista ku \u00e7mimi \u00ebsht\u00eb m\u00eb pak se 199 dollar\u00eb. E kryer.
Zgjidhje t\u00eb gatshme<\/h2>\n \nShpresoj se ju kam interesuar pak dhe q\u00eb keni marr\u00eb nj\u00eb mjet t\u00eb dobish\u00ebm n\u00eb arsenalin tuaj. N\u00ebse ndonj\u00ebher\u00eb do t'ju nevojitet t\u00eb b\u00ebni di\u00e7ka t\u00eb ngjashme, do t\u00eb dini drejtimin se ku t\u00eb shikoni.<\/p>\n
Megjithat\u00eb, nuk kan\u00eb t\u00eb gjith\u00eb koh\u00eb, durim dhe burime p\u00ebr t\u00eb krijuar indeksat bitmap nga e para. Sidomos ato m\u00eb t\u00eb avancuara, duke p\u00ebrdorur SIMD, p\u00ebr shembull.<\/p>\n
Fatmir\u00ebsisht, ka disa zgjidhje t\u00eb gatshme q\u00eb do t'ju ndihmojn\u00eb.
Bitmaps Roaring<\/h2>\n \nN\u00eb radh\u00eb t\u00eb par\u00eb, ka bibliotek\u00ebn e asaj fabulante t\u00eb bitmaps roaring p\u00ebr t\u00eb cil\u00ebn kam folur m\u00eb par\u00eb. Ajo p\u00ebrmban t\u00eb gjitha kontenier\u00ebt e nevojsh\u00ebm dhe operacionet bitore q\u00eb keni nevoj\u00eb p\u00ebr t\u00eb krijuar nj\u00eb indeks bitmap t\u00eb plot\u00eb.
Pilosa<\/h2>\n \nNj\u00eb produkt tjet\u00ebr q\u00eb mund t'ju ndihmoj\u00eb \u00ebsht\u00eb DBMS Pilosa, i cili n\u00eb thelb ka vet\u00ebm indeksat bitmap. Ky \u00ebsht\u00eb nj\u00eb zgjidhje relativisht e re, por po pushton zemrat me nj\u00eb shpejt\u00ebsi t\u00eb madhe.
Le t\u00eb shohim shpejt nj\u00eb shembull t\u00eb p\u00ebrdorimit t\u00eb Pilosa p\u00ebr t\u00eb p\u00ebrgjigjur n\u00eb nj\u00eb pyetje q\u00eb ju \u00ebsht\u00eb njohur m\u00eb par\u00eb.
Pas k\u00ebsaj, p\u00ebrdorim NOT n\u00eb fush\u00ebn \"expensive\", pastaj e nd\u00ebrp\u00ebrsejm\u00eb rezultatin (ose AND-ojm\u00eb) me fush\u00ebn \"terrace\" dhe me fush\u00ebn \"reservations\". Dhe n\u00eb fund, marrim rezultatin p\u00ebrfundimtar.
P\u00ebrfundim<\/h2>\n \n
\u00cbsht\u00eb mir\u00eb t\u00eb dihet p\u00ebr bitmap-indeksin, edhe n\u00ebse nuk ju nevojiten menj\u00ebher\u00eb. Le t\u00eb jen\u00eb nj\u00eb mjet tjet\u00ebr n\u00eb kutin\u00eb tuaj.<\/p>\n
Ne kemi shqyrtuar truket e ndryshme p\u00ebr rritjen e performanc\u00ebs p\u00ebr Go dhe ato gj\u00ebra q\u00eb kompajleri Go ende nuk i trajton shum\u00eb mir\u00eb. Kjo \u00ebsht\u00eb absolutisht di\u00e7ka e dobishme p\u00ebr \u00e7do programues n\u00eb Go.<\/p>\n
Kjo \u00ebsht\u00eb gjith\u00e7ka q\u00eb doja t\u00eb flisja. Faleminderit!habr.com<\/a><\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"\u0412\u0441\u0442\u0443\u043f\u0438\u0442\u0435\u043b\u044c\u043d\u043e\u0435 \u0441\u043b\u043e\u0432\u043e \u042f \u0432\u044b\u0441\u0442\u0443\u043f\u0438\u043b \u0441 \u044d\u0442\u0438\u043c \u0434\u043e\u043a\u043b\u0430\u0434\u043e\u043c \u043d\u0430 \u0430\u043d\u0433\u043b\u0438\u0439\u0441\u043a\u043e\u043c \u044f\u0437\u044b\u043a\u0435 \u043d\u0430 \u043a\u043e\u043d\u0444\u0435\u0440\u0435\u043d\u0446\u0438\u0438 GopherCon Russia 2019 \u0432 \u041c\u043e\u0441\u043a\u0432\u0435 \u0438 \u043d\u0430 \u0440\u0443\u0441\u0441\u043a\u043e\u043c \u2014 \u043d\u0430 \u043c\u0438\u0442\u0430\u043f\u0435 \u0432 \u041d\u0438\u0436\u043d\u0435\u043c \u041d\u043e\u0432\u0433\u043e\u0440\u043e\u0434\u0435. \u0420\u0435\u0447\u044c \u0432 \u043d\u0451\u043c \u0438\u0434\u0451\u0442 \u043e bitmap-\u0438\u043d\u0434\u0435\u043a\u0441\u0435 \u2014 \u043c\u0435\u043d\u0435\u0435 \u0440\u0430\u0441\u043f\u0440\u043e\u0441\u0442\u0440\u0430\u043d\u0451\u043d\u043d\u043e\u043c, \u0447\u0435\u043c B-tree, \u043d\u043e \u043d\u0435 \u043c\u0435\u043d\u0435\u0435 \u0438\u043d\u0442\u0435\u0440\u0435\u0441\u043d\u043e\u043c. \u0414\u0435\u043b\u044e\u0441\u044c \u0437\u0430\u043f\u0438\u0441\u044c\u044e \u0432\u044b\u0441\u0442\u0443\u043f\u043b\u0435\u043d\u0438\u044f \u043d\u0430 \u043a\u043e\u043d\u0444\u0435\u0440\u0435\u043d\u0446\u0438\u0438 \u043d\u0430 \u0430\u043d\u0433\u043b\u0438\u0439\u0441\u043a\u043e\u043c \u0438 \u0442\u0435\u043a\u0441\u0442\u043e\u0432\u043e\u0439 \u0440\u0430\u0441\u0448\u0438\u0444\u0440\u043e\u0432\u043a\u043e\u0439 \u043d\u0430 \u0440\u0443\u0441\u0441\u043a\u043e\u043c. \u041c\u044b \u0440\u0430\u0441\u0441\u043c\u043e\u0442\u0440\u0438\u043c, […]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":25469,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[688],"tags":[],"class_list":["post-33793","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-administrirovanie"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t
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