{"id":104459,"date":"2022-06-21T15:36:41","date_gmt":"2022-06-21T13:36:42","guid":{"rendered":"https:\/\/prohoster.info\/blog\/novosti-interneta\/facebook-predstavil-mehanizm-tmo-pozvolyayushhij-ekonomit-20-32-pamyati-na-serverah"},"modified":"2022-06-21T15:36:41","modified_gmt":"2022-06-21T13:36:42","slug":"facebook-predstavil-mehanizm-tmo-pozvolyayushhij-ekonomit-20-32-pamyati-na-serverah","status":"publish","type":"post","link":"https:\/\/prohoster.info\/pt\/blog\/news\/facebook-predstavil-mehanizm-tmo-pozvolyayushhij-ekonomit-20-32-pamyati-na-serverah","title":{"rendered":"O Facebook apresentou o mecanismo TMO, que permite economizar entre 20-32% de mem\u00f3ria nos servidores","gt_translate_keys":[{"key":"rendered","format":"text"}]},"content":{"rendered":"

Engenheiros do Facebook (proibido na RF) publicaram um relat\u00f3rio sobre a implementa\u00e7\u00e3o no ano passado da tecnologia TMO (Transparent Memory Offloading), que permite uma economia significativa de mem\u00f3ria operacional nos servidores ao deslocar dados secund\u00e1rios desnecess\u00e1rios para dispositivos de armazenamento mais baratos, como discos NVMe SSD. Segundo o Facebook, a aplica\u00e7\u00e3o do TMO permite uma economia de 20 a 32% de RAM em cada servidor. A solu\u00e7\u00e3o \u00e9 projetada para ser usada em infraestruturas onde os aplicativos s\u00e3o executados em cont\u00eaineres isolados. Os componentes do TMO, que operam do lado do n\u00facleo, j\u00e1 est\u00e3o inclu\u00eddos no n\u00facleo do Linux. <\/p>\n

Do lado do n\u00facleo do Linux, o funcionamento da tecnologia \u00e9 garantido pelo subsistema PSI (Pressure Stall Information), dispon\u00edvel a partir da vers\u00e3o 4.20. O PSI j\u00e1 \u00e9 utilizado em v\u00e1rios manipuladores de escassez de mem\u00f3ria e permite analisar informa\u00e7\u00f5es sobre o tempo de espera para obter diferentes recursos (CPU, mem\u00f3ria, I\/O). Com o PSI, os manipuladores no espa\u00e7o de usu\u00e1rio podem avaliar com mais precis\u00e3o o n\u00edvel de carga do sistema e a natureza da desacelera\u00e7\u00e3o, permitindo identificar desvios na fase inicial, quando ainda n\u00e3o afetam significativamente o desempenho. <\/p>\n

No espa\u00e7o de usu\u00e1rio, o funcionamento do TMO \u00e9 garantido pelo componente Senpai, que, atrav\u00e9s do cgroup2, ajusta dinamicamente o limite de mem\u00f3ria para os cont\u00eaineres de aplicativos com base nos dados obtidos do PSI. O Senpai analisa os sinais de escassez de recursos atrav\u00e9s do PSI, avalia a sensibilidade dos aplicativos \u00e0 desacelera\u00e7\u00e3o do acesso \u00e0 mem\u00f3ria e tenta determinar o tamanho m\u00ednimo de mem\u00f3ria necess\u00e1rio para o cont\u00eainer, no qual os dados essenciais para a opera\u00e7\u00e3o permanecem na RAM, enquanto os dados secund\u00e1rios, que est\u00e3o em cache de arquivo ou n\u00e3o utilizados no momento, s\u00e3o deslocados para a parti\u00e7\u00e3o de swap.

\"O<\/center> <\/p>\n

Assim, a ess\u00eancia do TMO \u00e9 manter os processos em uma dieta rigorosa em termos de consumo de mem\u00f3ria, for\u00e7ando a transfer\u00eancia para a \u00e1rea de troca de p\u00e1ginas de mem\u00f3ria n\u00e3o utilizadas, cuja expuls\u00e3o n\u00e3o afeta significativamente o desempenho (por exemplo, p\u00e1ginas com c\u00f3digo utilizado apenas na inicializa\u00e7\u00e3o e dados usados uma \u00fanica vez no cache de disco). Ao contr\u00e1rio da expuls\u00e3o de informa\u00e7\u00f5es para a \u00e1rea de troca em resposta \u00e0 falta de mem\u00f3ria, no TMO, os dados s\u00e3o expulsos com base em previs\u00f5es proativas. <\/p>\n

Como um dos crit\u00e9rios para a expuls\u00e3o, \u00e9 utilizado a falta de acesso a uma p\u00e1gina de mem\u00f3ria durante 5 minutos. Essas p\u00e1ginas s\u00e3o chamadas de frias (cold memory page) e, em m\u00e9dia, representam cerca de 35% da mem\u00f3ria das aplica\u00e7\u00f5es (dependendo do tipo de aplica\u00e7\u00e3o, a varia\u00e7\u00e3o \u00e9 de 19% a 65%). Ao expulsar, considera-se a atividade relacionada \u00e0s p\u00e1ginas de mem\u00f3ria an\u00f4nimas (mem\u00f3ria alocada pela aplica\u00e7\u00e3o) e \u00e0 mem\u00f3ria utilizada no cache de arquivos (alocada pelo kernel). Em algumas aplica\u00e7\u00f5es, o consumo principal est\u00e1 relacionado \u00e0 mem\u00f3ria an\u00f4nima, mas em outras o cache de arquivos tamb\u00e9m \u00e9 significativo. Para evitar um desequil\u00edbrio na expuls\u00e3o da mem\u00f3ria para o cache, o TMO aplica um novo algoritmo de troca que expulsa p\u00e1ginas an\u00f4nimas e p\u00e1ginas associadas ao cache de arquivos de forma proporcional. <\/p>\n

A expuls\u00e3o de p\u00e1ginas raramente utilizadas para uma mem\u00f3ria mais lenta n\u00e3o afeta muito o desempenho, mas permite reduzir significativamente os custos com hardware. Os dados s\u00e3o expulsos para discos SSD ou para uma \u00e1rea de troca comprimida na mem\u00f3ria RAM. Em termos de custo de armazenamento por byte de dados, o uso de NVMe SSD \u00e9 at\u00e9 10 vezes mais barato do que a compress\u00e3o na mem\u00f3ria RAM.

\"O<\/center>
\n
Fonte: opennet.ru<\/a> <\/p>","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"excerpt":{"rendered":"

\u0418\u043d\u0436\u0435\u043d\u0435\u0440\u044b \u0438\u0437 \u043a\u043e\u043c\u043f\u0430\u043d\u0438\u0438 Facebook (\u0437\u0430\u043f\u0440\u0435\u0449\u0435\u043d\u0430 \u0432 \u0420\u0424) \u043e\u043f\u0443\u0431\u043b\u0438\u043a\u043e\u0432\u0430\u043b\u0438 \u043e\u0442\u0447\u0451\u0442 \u043e \u0432\u043d\u0435\u0434\u0440\u0435\u043d\u0438\u0438 \u0432 \u043f\u0440\u043e\u0448\u043b\u043e\u043c \u0433\u043e\u0434\u0443 \u0442\u0435\u0445\u043d\u043e\u043b\u043e\u0433\u0438\u0438 TMO (Transparent Memory Offloading), \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0435\u0439 \u0437\u043d\u0430\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e \u044d\u043a\u043e\u043d\u043e\u043c\u0438\u0442\u044c \u043e\u043f\u0435\u0440\u0430\u0442\u0438\u0432\u043d\u0443\u044e \u043f\u0430\u043c\u044f\u0442\u044c \u043d\u0430 \u0441\u0435\u0440\u0432\u0435\u0440\u0430\u0445 \u0437\u0430 \u0441\u0447\u0451\u0442 \u0432\u044b\u0442\u0435\u0441\u043d\u0435\u043d\u0438\u044f \u043d\u0435 \u0442\u0440\u0435\u0431\u0443\u0435\u043c\u044b\u0445 \u0434\u043b\u044f \u0432\u044b\u043f\u043e\u043b\u043d\u0435\u043d\u0438\u044f \u0440\u0430\u0431\u043e\u0442\u044b \u0432\u0442\u043e\u0440\u0438\u0447\u043d\u044b\u0445 \u0434\u0430\u043d\u043d\u044b\u0445 \u043d\u0430 \u0431\u043e\u043b\u0435\u0435 \u0434\u0435\u0448\u0451\u0432\u044b\u0435 \u043d\u0430\u043a\u043e\u043f\u0438\u0442\u0435\u043b\u0438, \u0442\u0430\u043a\u0438\u0435 \u043a\u0430\u043a NVMe SSD-\u0434\u0438\u0441\u043a\u0438. \u041f\u043e \u043e\u0446\u0435\u043d\u043a\u0435 Facebook, \u043f\u0440\u0438\u043c\u0435\u043d\u0435\u043d\u0438\u0435 TMO \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u0435\u0442 \u044d\u043a\u043e\u043d\u043e\u043c\u0438\u0442\u044c \u043e\u0442 20 \u0434\u043e 32% […]<\/p>\n","protected":false,"gt_translate_keys":[{"key":"rendered","format":"html"}]},"author":1,"featured_media":104460,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[702],"tags":[],"class_list":["post-104459","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news"],"aioseo_notices":[],"aioseo_head":"\n\t\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\t\t\n\n","aioseo_head_json":{"title":"\ud83e\udd47Facebook apresentou o mecanismo TMO, permitindo economizar de 20 a 32% de mem\u00f3ria em servidores | ProHoster","description":"Engenheiros da empresa Facebook (proibida na RF) publicaram um relat\u00f3rio sobre a implementa\u00e7\u00e3o, no ano passado, da tecnologia TMO (Transparent Memory Offloading), que permite economizar significativamente a mem\u00f3ria RAM nos servidores.","canonical_url":"https:\/\/prohoster.info\/pt\/blog\/news\/facebook-predstavil-mehanizm-tmo-pozvolyayushhij-ekonomit-20-32-pamyati-na-serverah","robots":"max-image-preview:large","keywords":"","webmasterTools":{"miscellaneous":""},"schema":null,"og:locale":"pt_PT","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\udd47Facebook \u043f\u0440\u0435\u0434\u0441\u0442\u0430\u0432\u0438\u043b \u043c\u0435\u0445\u0430\u043d\u0438\u0437\u043c TMO, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0438\u0439 \u044d\u043a\u043e\u043d\u043e\u043c\u0438\u0442\u044c 20-32% \u043f\u0430\u043c\u044f\u0442\u0438 \u043d\u0430 \u0441\u0435\u0440\u0432\u0435\u0440\u0430\u0445 | ProHoster","og:description":"\u0418\u043d\u0436\u0435\u043d\u0435\u0440\u044b \u0438\u0437 \u043a\u043e\u043c\u043f\u0430\u043d\u0438\u0438 Facebook (\u0437\u0430\u043f\u0440\u0435\u0449\u0435\u043d\u0430 \u0432 \u0420\u0424) \u043e\u043f\u0443\u0431\u043b\u0438\u043a\u043e\u0432\u0430\u043b\u0438 \u043e\u0442\u0447\u0451\u0442 \u043e \u0432\u043d\u0435\u0434\u0440\u0435\u043d\u0438\u0438 \u0432 \u043f\u0440\u043e\u0448\u043b\u043e\u043c \u0433\u043e\u0434\u0443 \u0442\u0435\u0445\u043d\u043e\u043b\u043e\u0433\u0438\u0438 TMO (Transparent Memory Offloading), \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0435\u0439 \u0437\u043d\u0430\u0447\u0438\u0442\u0435\u043b\u044c\u043d\u043e \u044d\u043a\u043e\u043d\u043e\u043c\u0438\u0442\u044c \u043e\u043f\u0435\u0440\u0430\u0442\u0438\u0432\u043d\u0443\u044e \u043f\u0430\u043c\u044f\u0442\u044c \u043d\u0430 \u0441\u0435\u0440\u0432\u0435\u0440\u0430\u0445 \u0437\u0430 \u0441\u0447\u0451\u0442.","og:url":"https:\/\/prohoster.info\/pt\/blog\/news\/facebook-predstavil-mehanizm-tmo-pozvolyayushhij-ekonomit-20-32-pamyati-na-serverah","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":"2022-06-21T13:36:42+00:00","article:modified_time":"2022-06-21T13:36:42+00:00","article:publisher":"https:\/\/www.facebook.com\/prohoster","article:author":"https:\/\/www.facebook.com\/prohoster"},"aioseo_meta_data":{"post_id":"104459","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":null,"breadcrumb_settings":null,"limit_modified_date":false,"reviewed_by":null,"ai":null,"created":"2022-06-21 13:37:49","updated":"2022-10-01 20:35:20","focus_keyword":null,"additional_keywords":null,"truseo_locale":null},"gt_translate_keys":[{"key":"link","format":"url"}],"_links":{"self":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/posts\/104459","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/comments?post=104459"}],"version-history":[{"count":0,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/posts\/104459\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/media\/104460"}],"wp:attachment":[{"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/media?parent=104459"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/categories?post=104459"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/prohoster.info\/pt\/wp-json\/wp\/v2\/tags?post=104459"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}