{"id":370,"date":"2014-03-12T10:42:07","date_gmt":"2014-03-12T09:42:07","guid":{"rendered":"http:\/\/www.psinke.nl\/wordpress\/?p=370"},"modified":"2014-03-15T16:42:50","modified_gmt":"2014-03-15T15:42:50","slug":"improving-performance-by-tweaking-entropy-pool","status":"publish","type":"post","link":"http:\/\/www.psinke.nl\/blog\/improving-performance-by-tweaking-entropy-pool\/","title":{"rendered":"improving Oracle SOA performance by tweaking the entropy pool"},"content":{"rendered":"<div class=\"713e806d42c51d8462bbb5f4c1155083\" data-index=\"1\" style=\"float: none; margin:0px;\">\n<script type=\"text\/javascript\"><!--\r\ngoogle_ad_client = \"ca-pub-4223201538046844\";\r\n\/* standaardblok *\/\r\ngoogle_ad_slot = \"9522527129\";\r\ngoogle_ad_width = 320;\r\ngoogle_ad_height = 50;\r\n\/\/-->\r\n<\/script>\r\n<script type=\"text\/javascript\"\r\nsrc=\"http:\/\/pagead2.googlesyndication.com\/pagead\/show_ads.js\">\r\n<\/script>\n<\/div>\n<p>I stumbled upon <a title=\"Weblogic Server and entropy\" href=\"http:\/\/theheat.dk\/blog\/?p=1539\" target=\"_blank\">a nice blog post by Peter Lorenzen<\/a>\u00a0about the entropy generator in Linux, for creating random numbers (used in encryption and many other features).<\/p>\n<p>When you encounter Java performance problems (stalling and lagging), please read Peter&#8217;s blog carefully, I think it&#8217;s very informative. Also take note of the possible security issues he mentions.<\/p>\n<h2><span style=\"text-decoration: underline;\">Update<\/span><\/h2>\n<p>I&#8217;ve found another solution that was really helpful in getting our EM console up to speed. I&#8217;ve written a blog post on my company&#8217;s website. Check it out at <a title=\"Whitehorses blog\" href=\"http:\/\/blog.whitehorses.nl\/2014\/03\/14\/tweaking-the-entropy-pool-for-a-better-soa-performance\/\" target=\"_blank\">the Whitehorses Blog<\/a>. The TLDR; version is:<\/p>\n<p><em>I used the linux program <\/em><strong>haveged, <\/strong><em>which\u00a0is a userspace entropy daemon which is not dependent upon the standard mechanisms for harvesting randomness for the system entropy pool.\u00a0<\/em><\/p>\n<p><em>\u00a0After installation, the entropy pool is replenished much faster, so programs do not have to wait (or stall) when the entropy pool is depleted.<\/em><\/p>\n<figure style=\"width: 400px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/imgs.xkcd.com\/comics\/random_number.png \"><img loading=\"lazy\" decoding=\"async\" class=\" \" title=\"Random number\" alt=\"improving Oracle SOA performance by tweaking the entropy pool.\" src=\"http:\/\/imgs.xkcd.com\/comics\/random_number.png \" width=\"400\" height=\"144\" \/><\/a><figcaption class=\"wp-caption-text\">XKCD&#8217;s view on truly random numbers.<\/figcaption><\/figure>\n<!--CusAds0-->\n<div style=\"font-size: 0px; height: 0px; line-height: 0px; margin: 0; padding: 0; clear: both;\"><\/div>","protected":false},"excerpt":{"rendered":"<p>I stumbled upon a nice blog post by Peter Lorenzen\u00a0about the entropy generator in Linux, for creating random numbers (used in encryption and many other features). When you encounter Java performance problems (stalling and lagging), please read Peter&#8217;s blog carefully, I think it&#8217;s very informative. Also take note of the possible security issues he mentions&#8230;.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[255,3],"tags":[314,258,259,309,312,313,70,90,311,85,310,256,293],"class_list":["post-370","post","type-post","status-publish","format-standard","hentry","category-middleware","category-oracle-blog","tag-daemon","tag-em","tag-enterprise-manager","tag-entropy","tag-entropy-pool","tag-haveged","tag-java","tag-jre","tag-jvm","tag-performance","tag-random","tag-soa","tag-weblogic"],"jetpack_featured_media_url":"","_links":{"self":[{"href":"http:\/\/www.psinke.nl\/blog\/wp-json\/wp\/v2\/posts\/370","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.psinke.nl\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.psinke.nl\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.psinke.nl\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.psinke.nl\/blog\/wp-json\/wp\/v2\/comments?post=370"}],"version-history":[{"count":0,"href":"http:\/\/www.psinke.nl\/blog\/wp-json\/wp\/v2\/posts\/370\/revisions"}],"wp:attachment":[{"href":"http:\/\/www.psinke.nl\/blog\/wp-json\/wp\/v2\/media?parent=370"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.psinke.nl\/blog\/wp-json\/wp\/v2\/categories?post=370"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.psinke.nl\/blog\/wp-json\/wp\/v2\/tags?post=370"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}