{"id":161903,"date":"2026-02-20T17:11:55","date_gmt":"2026-02-20T15:11:55","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/razrabotchik-io_uring-vyyavil-v-qemu-problemu-v-50-80-raz-zamedlyavshuyu-fdmon-v-rezhime-prostoya"},"modified":"2026-02-20T17:11:55","modified_gmt":"2026-02-20T15:11:55","slug":"razrabotchik-io_uring-vyyavil-v-qemu-problemu-v-50-80-raz-zamedlyavshuyu-fdmon-v-rezhime-prostoya","status":"publish","type":"post","link":"https:\/\/prohoster.info\/et\/blog\/novosti-interneta\/razrabotchik-io_uring-vyyavil-v-qemu-problemu-v-50-80-raz-zamedlyavshuyu-fdmon-v-rezhime-prostoya","title":{"rendered":"Arendaja io_uring tuvastas QEMU's probleemi, mis aeglustas fdmoni 50-80 korda ooteasendis.","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Jens Axboe, io_uring'i ja CFQ, Deadline ja Noop sisendi\/v\u00e4ljundi planeerijate looja, pakkus QEMU emulaatori koodibaasi lisamiseks pat\u0161i, mis 50-80 korda v\u00e4hendab viivitusi, kui fdmon (file descriptor monitoring) t\u00f6\u00f6tab 'aio=io_uring' re\u017eiimis ja s\u00fcsteem on ooteolekus. <\/p>\n

Probleem tekkis, kuna ppoll() operatsioon viidi ootere\u017eiimi 499 ms ajaks, hoolimata sisendi\/v\u00e4ljundi olemasolust. Peamise s\u00fcndmuste t\u00f6\u00f6tlemise ts\u00fckli taastamiseks, mis peatati ppoll() t\u00f5ttu, pakuti v\u00e4lja pat\u0161, mis lisab SQE (Submission Queue Entry) salvestamise funktsiooni kutsumise, mis toob ppoll() ootere\u017eiimist v\u00e4lja. <\/p>\n

Probleem tekkis io_uring'i regressioonitesti k\u00e4igus virtuaalmasinatel<\/a> erinevate plokk-seadmetega. Jens t\u00f5i esile juhuslike ajastuste ilmnemise AHCI\/SATA seadmete kasutamisel 'aio=io_uring' re\u017eiimis, samas kui virtio-blk v\u00f5i nvme seadmetega konfigureerimisel l\u00f5petas testimine alati edukalt umbes sekundiga. T m\u00e4rkida, et probleem m\u00f5jutab k\u00f5iki plokk-seadmeid, kuid AHCI\/SATA seadmete puhul on viivituste esinemine k\u00f5ige v\u00e4ljendunum MMIO kasutamise t\u00f5ttu. <\/p>\n

Jens kirjeldas ka oma kogemust probleemide silumist AI-assistendi Claude abil. P\u00e4rast stsenaariumi m\u00e4\u00e4ratlemist, mis tekitas ajav\u00e4ltimise tingimused, edastas ta olemasolevad silumisandmed Claude'ile, andis juurdep\u00e4\u00e4su virtuaalmasinale ja pakkus v\u00e4lja t\u00f5en\u00e4olised p\u00f5hjused avastatud rikke m\u00e4\u00e4ratlemiseks. <\/p>\n

Claude otsustas testida, kas virtio-blk seadme kasutamisel t\u00f6\u00f6 aeglustub, ning k\u00e4ivitas selle jaoks arendaja pakutud destruktiivse stseeni, mis probleemiga kokku puutus. Testimise k\u00e4igus kustutati virtuaalses masinas plokk-seadmest \/dev\/vda esimesed 128 MB sisu. P\u00e4rast seda j\u00f5udis Claude j\u00e4reldusele, et probleem ei ole virtio-blk'is. Kui Jens juhtis AI-assistendi t\u00e4helepanu osa sisu kustutamisele \/dev\/vda, vastas ta 'Jah, ma tegin seda', ja p\u00e4rast palvet selle parandamiseks taastati virtuaalse ketta \/dev\/vda toimivus. T m\u00e4rgitud, et AI-assistendi kasutamine aitas paremini m\u00f5ista QEMU erinevate s\u00fcndmuste t\u00f6\u00f6tlemise ts\u00fcklite erip\u00e4ra. <\/p>\n

Oluline on m\u00e4rkida, et probleemi oli \u00fcsna raske tuvastada, kuna s\u00fcnteetilistes testides ei registreerita aeglustumist, kuna ajav\u00e4ltimise p\u00f5hjustab s\u00fcndmuste t\u00f6\u00f6tlemise ts\u00fckli \u00e4rkamine ppoll'i t\u00f5ttu teise tegevuse t\u00f5ttu ning s\u00fcnteetilised sisendi\/v\u00e4ljundi testid ei t\u00f6\u00f6tle saadud andmeid. Aeglustumine sai m\u00e4rgatavamaks mitme usleep() kutsumise lisamisel andmete t\u00f6\u00f6tlemise simuleerimiseks. <\/p>\n

Enne parandamist ootere\u017eiimis s\u00fcsteemis: time sudo .\/iotest \/dev\/sda Sooritatud: 25.76 secs fish v\u00e4line usr time 6.19 millis 783.00 micros 5.41 millis sys time 12.43 millis 642.00 micros 11.79 millis <\/p>\n

P\u00e4rast parandamist ootere\u017eiimis s\u00fcsteemis: time sudo .\/iotest \/dev\/sda Sooritatud: 1.30 secs fish v\u00e4line usr time 2.14 millis 0.14 millis 2.00 millis sys time 16.93 millis 1.16 millis 15.76 millis
\n
Allikas: opennet.ru<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

\u0419\u0435\u043d\u0441 \u042d\u043a\u0441\u0431\u043e (Jens Axboe), \u0441\u043e\u0437\u0434\u0430\u0442\u0435\u043b\u044c io_uring \u0438 \u043f\u043b\u0430\u043d\u0438\u0440\u043e\u0432\u0449\u0438\u043a\u043e\u0432 \u0432\u0432\u043e\u0434\u0430\/\u0432\u044b\u0432\u043e\u0434\u0430 CFQ, Deadline \u0438 Noop, \u043f\u0440\u0435\u0434\u043b\u043e\u0436\u0438\u043b \u0434\u043b\u044f \u0432\u043a\u043b\u044e\u0447\u0435\u043d\u0438\u044f \u0432 \u043a\u043e\u0434\u043e\u0432\u0443\u044e \u0431\u0430\u0437\u0443 \u044d\u043c\u0443\u043b\u044f\u0442\u043e\u0440\u0430 QEMU \u043f\u0430\u0442\u0447, \u0432 50-80 \u0440\u0430\u0437 \u0441\u043e\u043a\u0440\u0430\u0449\u0430\u044e\u0449\u0438\u0439 \u0437\u0430\u0434\u0435\u0440\u0436\u043a\u0438 \u043f\u0440\u0438 \u0440\u0430\u0431\u043e\u0442\u0435 fdmon (file descriptor monitoring) \u0432 \u0440\u0435\u0436\u0438\u043c\u0435 «aio=io_uring» \u0438 \u043d\u0430\u0445\u043e\u0436\u0434\u0435\u043d\u0438\u0438 \u0441\u0438\u0441\u0442\u0435\u043c\u044b \u0432 \u0441\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u0438 \u043f\u0440\u043e\u0441\u0442\u043e\u044f (idle). \u041f\u0440\u043e\u0431\u043b\u0435\u043c\u0430 \u043f\u0440\u043e\u044f\u0432\u043b\u044f\u043b\u0430\u0441\u044c \u0438\u0437-\u0437\u0430 \u043f\u0435\u0440\u0435\u0432\u043e\u0434\u0430 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u0438 ppoll() \u0432 \u0441\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u0438 \u0441\u043d\u0430 \u0441 \u0442\u0430\u0439\u043c\u0430\u0443\u0442\u043e\u043c 499 […]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":8,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[702],"tags":[],"class_list":["post-161903","post","type-post","status-publish","format-standard","hentry","category-novosti-interneta"],"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\udd47io_uring arendaja tuvastas QEMU-s probleemi, mis aeglustas fdmon'i ootere\u017eiimis 50-80 korda | ProHoster","description":"Jens Axboe, io_uring'i ja CFQ, Deadline ja Noop sisend\/v\u00e4ljund planeerijate looja, pakkus QEMU emulatori koodibaasi lisamiseks pat\u0161i, mis v\u00e4hendab fdmon'i (faili descriptor'i j\u00e4lgimise) viivitusi 50-80 korda, t\u00f6\u00f6tades re\u017eiimis \"aio=io_uring\" ja olles s\u00fcsteemis ootere\u017eiimis. Probleem tekkis, kuna ppoll() operatsioon viidi ootere\u017eiimi 499","canonical_url":"https:\/\/prohoster.info\/et\/blog\/novosti-interneta\/razrabotchik-io_uring-vyyavil-v-qemu-problemu-v-50-80-raz-zamedlyavshuyu-fdmon-v-rezhime-prostoya","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\u0420\u0430\u0437\u0440\u0430\u0431\u043e\u0442\u0447\u0438\u043a io_uring \u0432\u044b\u044f\u0432\u0438\u043b \u0432 QEMU \u043f\u0440\u043e\u0431\u043b\u0435\u043c\u0443, \u0432 50-80 \u0440\u0430\u0437 \u0437\u0430\u043c\u0435\u0434\u043b\u044f\u0432\u0448\u0443\u044e fdmon \u0432 \u0440\u0435\u0436\u0438\u043c\u0435 \u043f\u0440\u043e\u0441\u0442\u043e\u044f | ProHoster","og:description":"\u0419\u0435\u043d\u0441 \u042d\u043a\u0441\u0431\u043e (Jens Axboe), \u0441\u043e\u0437\u0434\u0430\u0442\u0435\u043b\u044c io_uring \u0438 \u043f\u043b\u0430\u043d\u0438\u0440\u043e\u0432\u0449\u0438\u043a\u043e\u0432 \u0432\u0432\u043e\u0434\u0430\/\u0432\u044b\u0432\u043e\u0434\u0430 CFQ, Deadline \u0438 Noop, \u043f\u0440\u0435\u0434\u043b\u043e\u0436\u0438\u043b \u0434\u043b\u044f \u0432\u043a\u043b\u044e\u0447\u0435\u043d\u0438\u044f \u0432 \u043a\u043e\u0434\u043e\u0432\u0443\u044e \u0431\u0430\u0437\u0443 \u044d\u043c\u0443\u043b\u044f\u0442\u043e\u0440\u0430 QEMU \u043f\u0430\u0442\u0447, \u0432 50-80 \u0440\u0430\u0437 \u0441\u043e\u043a\u0440\u0430\u0449\u0430\u044e\u0449\u0438\u0439 \u0437\u0430\u0434\u0435\u0440\u0436\u043a\u0438 \u043f\u0440\u0438 \u0440\u0430\u0431\u043e\u0442\u0435 fdmon (file descriptor monitoring) \u0432 \u0440\u0435\u0436\u0438\u043c\u0435 "aio=io_uring" \u0438 \u043d\u0430\u0445\u043e\u0436\u0434\u0435\u043d\u0438\u0438 \u0441\u0438\u0441\u0442\u0435\u043c\u044b \u0432 \u0441\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u0438 \u043f\u0440\u043e\u0441\u0442\u043e\u044f (idle). \u041f\u0440\u043e\u0431\u043b\u0435\u043c\u0430 \u043f\u0440\u043e\u044f\u0432\u043b\u044f\u043b\u0430\u0441\u044c \u0438\u0437-\u0437\u0430 \u043f\u0435\u0440\u0435\u0432\u043e\u0434\u0430 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u0438 ppoll() \u0432 \u0441\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u0438 \u0441\u043d\u0430 \u0441 \u0442\u0430\u0439\u043c\u0430\u0443\u0442\u043e\u043c 499","og:url":"https:\/\/prohoster.info\/et\/blog\/novosti-interneta\/razrabotchik-io_uring-vyyavil-v-qemu-problemu-v-50-80-raz-zamedlyavshuyu-fdmon-v-rezhime-prostoya","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":"2026-02-20T15:11:55+00:00","article:modified_time":"2026-02-20T15:11:55+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":{"post_id":"161903","title":null,"description":null,"keywords":null,"keyphrases":null,"primary_term":null,"canonical_url":null,"og_title":null,"og_description":null,"og_object_type":"default","og_image_type":"default","og_image_url":null,"og_image_width":null,"og_image_height":null,"og_image_custom_url":null,"og_image_custom_fields":null,"og_video":null,"og_custom_url":null,"og_article_section":null,"og_article_tags":null,"twitter_use_og":false,"twitter_card":"default","twitter_image_type":"default","twitter_image_url":null,"twitter_image_custom_url":null,"twitter_image_custom_fields":null,"twitter_title":null,"twitter_description":null,"schema":{"blockGraphs":[],"customGraphs":[],"default":{"data":{"Article":[],"Course":[],"Dataset":[],"FAQPage":[],"Movie":[],"Person":[],"Product":[],"ProductReview":[],"Car":[],"Recipe":[],"Service":[],"SoftwareApplication":[],"WebPage":[]},"graphName":"","isEnabled":true},"graphs":[]},"schema_type":"default","schema_type_options":null,"pillar_content":false,"robots_default":true,"robots_noindex":false,"robots_noarchive":false,"robots_nosnippet":false,"robots_nofollow":false,"robots_noimageindex":false,"robots_noodp":false,"robots_notranslate":false,"robots_max_snippet":null,"robots_max_videopreview":null,"robots_max_imagepreview":"large","priority":null,"frequency":null,"local_seo":null,"seo_analyzer_scan_date":"2026-02-20 15:12:29","breadcrumb_settings":null,"limit_modified_date":false,"reviewed_by":null,"ai":null,"created":"2026-02-20 15:11:55","updated":"2026-02-20 15:12:29"},"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/posts\/161903","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\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/comments?post=161903"}],"version-history":[{"count":1,"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/posts\/161903\/revisions"}],"predecessor-version":[{"id":164173,"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/posts\/161903\/revisions\/164173"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/media?parent=161903"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/categories?post=161903"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/et\/wp-json\/wp\/v2\/tags?post=161903"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}