Akatswiri ochokera ku Facebook (oletsedwa ku Russian Federation) adasindikiza lipoti la kukhazikitsidwa kwa teknoloji ya TMO (Transparent Memory Offloading), yomwe imalola kupulumutsa kwakukulu mu RAM pa seva pochotsa deta yachiwiri yosafunikira kuti igwire ntchito kumagalimoto otsika mtengo, monga NVMe. SSD - disks. Facebook ikuyerekeza kuti kugwiritsa ntchito TMO kumatha kusunga 20 mpaka 32% ya RAM pa seva iliyonse. Njira yothetsera vutoli idapangidwa kuti igwiritsidwe ntchito m'magawo omwe mapulogalamu amayendetsedwa muzotengera zakutali. Zigawo za Kernel-side za TMO zaphatikizidwa kale mu Linux kernel.
Pa mbali ya Linux kernel, teknoloji imathandizidwa ndi PSI (Pressure Stall Information) subsystem, yomwe ilipo kuyambira ndi kumasulidwa 4.20. PSI imagwiritsidwa ntchito kale m'malo osiyanasiyana osakumbukira kukumbukira ndipo imakupatsani mwayi wosanthula zambiri za nthawi yodikira kuti mupeze zinthu zosiyanasiyana (CPU, memory, I/O). Ndi PSI, mapurosesa a malo ogwiritsira ntchito amatha kuwunika molondola kuchuluka kwa katundu wamakina ndi njira zochepetsera, kulola kuti zolakwika zidziwike msanga, zisanakhudze magwiridwe antchito.
Pamalo ogwiritsira ntchito, TMO imaperekedwa ndi gawo la Senpai, lomwe, kupyolera mu cgroup2, limasintha malire a kukumbukira kwazitsulo zogwiritsira ntchito potengera zomwe zalandilidwa kuchokera ku PSI. Senpai amasanthula zizindikiro za kuyambika kwa kusowa kwazinthu kudzera pa PSI, amawunika kukhudzika kwa mapulogalamu kuti achepetse mwayi wofikira kukumbukira ndikuyesa kudziwa kukula kwa kukumbukira komwe kumafunikira ndi chidebe, pomwe deta yofunikira kuti igwire ntchito imakhalabe mu RAM, ndi zomwe zikutsatira. Zomwe zakhazikitsidwa mu cache ya fayilo kapena zomwe sizikugwiritsidwa ntchito mwachindunji pakadali pano, zimakakamizika kugawa magawo.
Chifukwa chake, chofunikira kwambiri cha TMO ndikusunga njira pazakudya zokhwima potengera kukumbukira kukumbukira, kukakamiza kusinthanitsa masamba osagwiritsidwa ntchito omwe kuchotsedwa kwawo sikumakhudza kwambiri magwiridwe antchito (mwachitsanzo, masamba okhala ndi code yomwe imagwiritsidwa ntchito poyambira, ndikugwiritsa ntchito kamodzi. deta mu disk cache). Mosiyana ndi kuthamangitsa zidziwitso kugawo losinthana poyankha kukakamizidwa kukumbukira, mu data ya TMO imachotsedwa kutengera kulosera kwachangu.
Chimodzi mwazinthu zothamangitsidwa ndikusowa mwayi wofikira patsamba la kukumbukira kwa mphindi 5. Masamba oterowo amatchedwa masamba okumbukira ozizira ndipo pafupifupi amapanga pafupifupi 35% ya kukumbukira ntchito (kutengera mtundu wa ntchito, pali osiyanasiyana kuchokera 19% mpaka 65%). Preemption imaganizira zochitika zomwe zimagwirizanitsidwa ndi masamba okumbukira osadziwika (chikumbutso choperekedwa ndi pulogalamu) ndi kukumbukira komwe kumagwiritsidwa ntchito posungira mafayilo (operekedwa ndi kernel). M'mapulogalamu ena, kugwiritsa ntchito kwakukulu ndikokumbukira mosadziwika, koma kwinanso posungira mafayilo ndikofunikira. Kuti mupewe kusalingana kwa kuthamangitsidwa kwa cache, TMO imagwiritsa ntchito algorithm yatsopano yomwe imachotsa masamba osadziwika ndi masamba okhudzana ndi cache ya fayilo molingana.
Kukankhira masamba omwe sagwiritsidwa ntchito pafupipafupi kuti akumbukire pang'onopang'ono sikumakhudza kwambiri magwiridwe antchito, koma kumatha kuchepetsa mtengo wa Hardware. Deta imasunthidwa ku ma drive a SSD kapena kumalo osinthira ophatikizika mu RAM. Pankhani ya mtengo wosungira baiti ya data, kugwiritsa ntchito NVMe SSD ndikotsika mtengo mpaka 10 kuposa kugwiritsa ntchito compression mu RAM.
Source: opennet.ru