{"id":37236,"date":"2018-03-14T16:48:07","date_gmt":"2018-03-14T15:48:07","guid":{"rendered":"http:\/\/www.planet3dnow.de\/cms\/?p=37236"},"modified":"2018-03-16T23:09:00","modified_gmt":"2018-03-16T22:09:00","slug":"amd-epyc-verliert-kaum-leistung-durch-spectre-v2-fix-retpoline","status":"publish","type":"post","link":"https:\/\/www.planet3dnow.de\/cms\/37236-amd-epyc-verliert-kaum-leistung-durch-spectre-v2-fix-retpoline\/","title":{"rendered":"AMD<\/span> Epyc verliert kaum Leistung durch Spectre-v2-Fix Retpoline"},"content":{"rendered":"

Nach Bekannt\u00adwer\u00adden der Pro\u00adzes\u00adsor-Sicher\u00adheits\u00adl\u00fc\u00adcken<\/a> Melt\u00addown und Spect\u00adre wur\u00adden hek\u00adtisch ers\u00adte Fixes oder im Jar\u00adgon \u201cLin\u00adde\u00adrun\u00adgen\u201d ver\u00ad\u00f6f\u00adfent\u00adlicht, da ins\u00adbe\u00adson\u00adde\u00adre bei den Betrei\u00adbern von vSer\u00advern und Cloud-Ser\u00advern schnell eine L\u00f6sung her muss\u00adte, denn die\u00adse Sys\u00adtem\u00adgat\u00adtung ist am st\u00e4rks\u00adten bedroht davon. Das Feed\u00adback der Betrei\u00adber fiel dabei je nach Ser\u00adver\u00adtyp ver\u00adhee\u00adrend aus. Von 20 %, 30 %, 40 % Leis\u00adtungs\u00adver\u00adlust war die Rede, ins\u00adbe\u00adson\u00adde\u00adre bei I\/O\u2011lastigen Aufgaben.<\/p>\n

Von Melt\u00addown ist AMD<\/span> bekannt\u00adlich nicht betrof\u00adfen. Inzwi\u00adschen sind zwei Mona\u00adte ver\u00adgan\u00adgen und die Fixes sind gereift, eben\u00adfalls die gegen die bei\u00adden Spect\u00adre-L\u00fccken. Dabei gibt es zwei kom\u00adplett unter\u00adschied\u00adli\u00adche Arten des Her\u00adan\u00adge\u00adhens: In der Linux-Welt ver\u00adsucht man, Spect\u00adre mit der Ret\u00adpo\u00adli\u00adne-Tech\u00adnik zu lin\u00addern, Micro\u00adsoft geht mit Win\u00addows den Weg \u00fcber zus\u00e4tz\u00adli\u00adche Befeh\u00adle, die per Micro\u00adcode in den Pro\u00adzes\u00adso\u00adren nach\u00adge\u00adr\u00fcs\u00adtet wer\u00adden m\u00fcssen.<\/p>\n

Auf Pho\u00adro\u00adnix ist vor eini\u00adgen Tagen ein Arti\u00adkel erschie\u00adnen<\/a>, der die Aus\u00adwir\u00adkun\u00adgen der ver\u00adschie\u00adde\u00adnen Fixes auf den Ser\u00adver-Pro\u00adzes\u00adsor AMD<\/span> Epyc auf\u00adzeigt. Dabei wird klar, wes\u00adhalb AMD<\/span> zu jeder pas\u00adsen\u00adden Gele\u00adgen\u00adheit betont, dass man Spect\u00adre v2 ger\u00adne mit dem Linux-Aus\u00adweg Ret\u00adpo\u00adli\u00adne begeg\u00adnen w\u00fcr\u00adde<\/a>, eben\u00adso unter Win\u00addows. Denn die Aus\u00adwir\u00adkun\u00adgen von Ret\u00adpo\u00adli\u00adne auf die Leis\u00adtung von Epyc sind ver\u00adschwin\u00addend gering. Dabei darf in Anbe\u00adtracht der Bench\u00admarks nicht \u00fcber\u00adse\u00adhen wer\u00adden, dass der getes\u00adte\u00adte Linux-Ker\u00adnel 4.16 gene\u00adrell etwas lang\u00adsa\u00admer zu sein scheint als der \u00e4lte\u00adre 4.14, ver\u00admut\u00adlich auch weil bei 4.16 die Spect\u00adre-v1-Fixes grund\u00ads\u00e4tz\u00adlich akti\u00adviert sind. Die wei\u00adte\u00adren getes\u00adte\u00adten Vari\u00adan\u00adten umfassen:<\/p>\n

For this AMD<\/span> EPYC<\/span> Linux ker\u00adnel bench\u00admar\u00adking the fol\u00adlo\u00adwing con\u00adfi\u00adgu\u00adra\u00adti\u00adons were tested:<\/p>\n

- Linux 4.14.0 sta\u00adble that does\u00adn\u2019t con\u00adtain any Spect\u00adre V1<\/span> or V2<\/span> miti\u00adga\u00adti\u00adon for the EPYC<\/span> system.<\/p>\n

- Linux 4.14.24 as the latest 4.14 sta\u00adble point release at the time of test\u00ading that includes both __user poin\u00adter sani\u00adtiza\u00adti\u00adon for Spect\u00adre Vari\u00adant One and back\u00adpor\u00adted full AMD<\/span> Ret\u00adpo\u00adli\u00adne pro\u00adtec\u00adtion for Spect\u00adre Vari\u00adant Two.<\/p>\n

- Linux 4.15.0 sta\u00adble that con\u00adtai\u00adned full AMD<\/span> Ret\u00adpo\u00adli\u00adne pro\u00adtec\u00adtion but that release had\u00adn\u2019t offe\u00adred any Spect\u00adre V1<\/span> protection.<\/p>\n

- Linux 4.16 Git from this week offe\u00adring both user poin\u00adter sani\u00adtiza\u00adti\u00adon and full AMD<\/span> Ret\u00adpo\u00adli\u00adne protection.<\/p>\n

- Linux 4.16 Git from the same build but dis\u00adab\u00adling the Ret\u00adpo\u00adli\u00adne sup\u00adport via the \u201cspectre_v2=off\u201d ker\u00adnel com\u00admand-line opti\u00adon. This though still lea\u00adves Spect\u00adre V1<\/span> pro\u00adtec\u00adtion in place.<\/p><\/blockquote>\n

Eini\u00adge Tage zuvor f\u00fchrt Pho\u00adro\u00adnix einen \u00e4hn\u00adli\u00adchen Test auf einem Ser\u00adver mit Intel<\/a>-Xeon-Gold-6138-CPUs durch. Dort trat der Leis\u00adtungs\u00adver\u00adlust infol\u00adge der neu\u00aden Sicher\u00adheits\u00adfea\u00adtures weit deut\u00adli\u00adcher zum Vor\u00adschein, nat\u00fcr\u00adlich auch des\u00adwe\u00adgen, da auf Intel-Ser\u00advern zus\u00e4tz\u00adlich gegen Melt\u00addown gepatcht wer\u00adden muss.<\/p>\n","protected":false},"excerpt":{"rendered":"

Ein Arti\u00adkel, der die Aus\u00adwir\u00adkun\u00adgen der ver\u00adschie\u00adde\u00adnen Fixes auf den Ser\u00adver-Pro\u00adzes\u00adsor AMD<\/span> Epyc auf\u00adzeigt, offen\u00adbart, wes\u00adhalb AMD<\/span> zu jeder pas\u00adsen\u00adden Gele\u00adgen\u00adheit betont, dass man Spect\u00adre ger\u00adne mit der Linux-Vari\u00adan\u00adte Ret\u00adpo\u00adli\u00adne begeg\u00adnen w\u00fcr\u00adde, eben\u00adso unter Win\u00addows. Denn die Aus\u00adwir\u00adkun\u00adgen von Ret\u00adpo\u00adli\u00adne auf die Leis\u00adtung von Epyc sind ver\u00adschwin\u00addend gering bis kaum vor\u00adhan\u00adden. (\u2026) Wei\u00adter\u00adle\u00adsen \u00bb<\/a><\/p>\n","protected":false},"author":2,"featured_media":32569,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"wp_typography_post_enhancements_disabled":false,"ngg_post_thumbnail":0,"footnotes":""},"categories":[12],"tags":[985,1419,1432,1420],"class_list":["post-37236","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-aktuelles","tag-linux","tag-meltdown","tag-retpoline","tag-spectre","entry"],"share_on_mastodon":{"url":"","error":""},"_links":{"self":[{"href":"https:\/\/www.planet3dnow.de\/cms\/wp-json\/wp\/v2\/posts\/37236","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.planet3dnow.de\/cms\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.planet3dnow.de\/cms\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.planet3dnow.de\/cms\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.planet3dnow.de\/cms\/wp-json\/wp\/v2\/comments?post=37236"}],"version-history":[{"count":15,"href":"https:\/\/www.planet3dnow.de\/cms\/wp-json\/wp\/v2\/posts\/37236\/revisions"}],"predecessor-version":[{"id":37359,"href":"https:\/\/www.planet3dnow.de\/cms\/wp-json\/wp\/v2\/posts\/37236\/revisions\/37359"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.planet3dnow.de\/cms\/wp-json\/wp\/v2\/media\/32569"}],"wp:attachment":[{"href":"https:\/\/www.planet3dnow.de\/cms\/wp-json\/wp\/v2\/media?parent=37236"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.planet3dnow.de\/cms\/wp-json\/wp\/v2\/categories?post=37236"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.planet3dnow.de\/cms\/wp-json\/wp\/v2\/tags?post=37236"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}