{"id":239,"date":"2008-08-05T23:37:53","date_gmt":"2008-08-06T07:37:53","guid":{"rendered":"http:\/\/www.khaitan.org\/blog\/?p=239"},"modified":"2008-08-05T23:37:53","modified_gmt":"2008-08-06T07:37:53","slug":"java-technologies-at-yahoo","status":"publish","type":"post","link":"https:\/\/www.khaitan.org\/blog\/2008\/08\/java-technologies-at-yahoo\/","title":{"rendered":"Java Technologies at Yahoo!"},"content":{"rendered":"<p>Yesterday, I attended a <a href=\"http:\/\/www.sdforum.org\/index.cfm?fuseaction=Calendar.eventDetail&amp;eventID=13125\">talk<\/a> at SDForum presented by Dean Yu and Joshua Blatt of the Java platform team at Yahoo! The Java platform team centralizes the Java efforts for Yahoo&#8217;s non-open source efforts. I say non-open source as\u00a0the platform team\u00a0covers everything except things like Hadoop, etc. which are in the public domain.<\/p>\n<p>Java as a technology is not native to Yahoo! The platform at Yahoo! was primarily C\/C++ and PHP at the frontend (mostly). Java came through several acquisitions which were running Java stack, notably:<\/p>\n<ul>\n<li>1998 Classic Games, Sprtasy<\/li>\n<li>2002 Hotjobs<\/li>\n<li>2003 Overture (Altavista)<\/li>\n<li>2004 Kelkoo, Musimatch<br \/>\n\u00a0<\/li>\n<\/ul>\n<p>Here are the raw bytes from the session:<\/p>\n<ul>\n<li>Tomcat + jboss efforts for securing them<\/li>\n<li>Mostly LAMP stack at Yahoo!<\/li>\n<li>Rate limiting using Apache modules\u00a0<\/li>\n<li>Runs apache in multiple process mode<\/li>\n<li>Y! data streams for keeping application specific stores and pushing data around (Yahoo&#8217;s proprietary message bus like implementation)<\/li>\n<li>Integration using JNI to C++ code using <a href=\"http:\/\/www.swig.org\/Doc1.3\/Java.html\">Swig<\/a> for wrapper generation<\/li>\n<li>All security related code is in C++; helps maintain a single language code-base. Hence, wide JNI use from app tier<\/li>\n<li>Uses IPC Bridge\u00a0for coarse grained calls to non-thread safe libraries (JNI has multi-threading issues)<\/li>\n<li>Group dedicated to creating JNI wrappers of native code<\/li>\n<li>JNI performance FUD<\/li>\n<li>Java to Native C++ code via JNI\u00a0&lt; 20 nano seconds (Cool!) compare this with Java to Java &lt; 1 nano seconds. Big difference but nano seconds compared to network latencies of seconds<\/li>\n<li>String functions to native code via JNI\u00a0take &gt; 3ms coz of UTF-16 to UTF-8 character conversion issues<\/li>\n<li>JNI Multi-threading issues are solved by IPC bridge shared memory and TCP over loopback<\/li>\n<li>JSVC Apache commons daemon for loading privileged data during Tomcat startup and then running in low privilege mode<\/li>\n<li>Like Multi-process Apache, a new architecture for multi-process Tomcat being baked<\/li>\n<li>Software project management using Maven (Maven &#8212; awww!)<\/li>\n<li>Automatic builds using <a href=\"http:\/\/cruisecontrol.sourceforge.net\/\">Cruise control<\/a>\u00a0and <a href=\"http:\/\/hudson.gotdns.com\/wiki\/display\/HUDSON\/Meet+Hudson\">Hudson<\/a><\/li>\n<li>RPM-based software deployment to 100s of nodes<\/li>\n<\/ul>\n<p>\u00a0<\/p>\n<p>\u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Yesterday, I attended a talk at SDForum presented by Dean Yu and Joshua Blatt of the Java platform team at Yahoo! The Java platform team centralizes the Java efforts for Yahoo&#8217;s non-open source efforts. I say non-open source as\u00a0the platform team\u00a0covers everything except things like Hadoop, etc. which are in the public domain. Java as [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[10,70],"tags":[128,129,303,138,317],"_links":{"self":[{"href":"https:\/\/www.khaitan.org\/blog\/wp-json\/wp\/v2\/posts\/239"}],"collection":[{"href":"https:\/\/www.khaitan.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.khaitan.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.khaitan.org\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.khaitan.org\/blog\/wp-json\/wp\/v2\/comments?post=239"}],"version-history":[{"count":0,"href":"https:\/\/www.khaitan.org\/blog\/wp-json\/wp\/v2\/posts\/239\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.khaitan.org\/blog\/wp-json\/wp\/v2\/media?parent=239"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.khaitan.org\/blog\/wp-json\/wp\/v2\/categories?post=239"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.khaitan.org\/blog\/wp-json\/wp\/v2\/tags?post=239"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}