{"id":155,"date":"2011-08-07T20:38:38","date_gmt":"2011-08-07T20:38:38","guid":{"rendered":"http:\/\/choudhury.com\/blog\/?p=155"},"modified":"2011-08-07T21:08:49","modified_gmt":"2011-08-07T21:08:49","slug":"troubleshooting-a-java-program","status":"publish","type":"post","link":"https:\/\/choudhury.com\/blog\/2011\/08\/07\/troubleshooting-a-java-program\/","title":{"rendered":"Troubleshooting a Java program"},"content":{"rendered":"

Useful command to know about, if you have the JDK (Java 6 update 7 or newer) installed. In the bin directory of the JDK, there is a tool called jvisualvm, to launch it, run the command<\/p>\n

jvisualvm<\/div><\/div>\n

VisualVM allows to troubleshoot and profile a java application, the official guide here<\/a>. JVisualVM is really handy, it has options to grab the memory\/cpu snapshots and you get graphs of CPU and heap dump usage. It also has menu option called “Compare Memory Snapshots” where you can compare the visualvm memory snapshots.<\/p>\n

\"\"<\/a><\/p>\n

Another useful command to know about, (again in the bin directory of the jdk) is jmap<\/strong> which you can use to get heap dumps to analyse.<\/p>\n

jmap -dump:live,format=b,file=<filename> <PID><\/div><\/div>\n

Where: “live” means get only information about the live objects. “b” is specifying the dump to a binary file.
\nTo troubleshoot memory problems, it maybe worthwhile to take a couple of heapdumps periodically so that can see what’s changing between the dumps. <\/p>\n

The tool that I’ve used to inspect heap dumps is MAT<\/a>, it has quite nice UI.<\/p>\n

Good luck in your troubleshooting! <\/p>\n","protected":false},"excerpt":{"rendered":"

Useful command to know about, if you have the JDK (Java 6 update 7 or newer) installed. In the bin directory of the JDK, there is a tool called jvisualvm, to launch it, run the command jvisualvm VisualVM allows to troubleshoot and profile a java application, the official guide here. JVisualVM is really handy, it … <\/p>\n

Continue reading “Troubleshooting a Java program”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[3],"tags":[],"class_list":["post-155","post","type-post","status-publish","format-standard","hentry","category-java"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/choudhury.com\/blog\/wp-json\/wp\/v2\/posts\/155","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/choudhury.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/choudhury.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/choudhury.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/choudhury.com\/blog\/wp-json\/wp\/v2\/comments?post=155"}],"version-history":[{"count":13,"href":"https:\/\/choudhury.com\/blog\/wp-json\/wp\/v2\/posts\/155\/revisions"}],"predecessor-version":[{"id":170,"href":"https:\/\/choudhury.com\/blog\/wp-json\/wp\/v2\/posts\/155\/revisions\/170"}],"wp:attachment":[{"href":"https:\/\/choudhury.com\/blog\/wp-json\/wp\/v2\/media?parent=155"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/choudhury.com\/blog\/wp-json\/wp\/v2\/categories?post=155"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/choudhury.com\/blog\/wp-json\/wp\/v2\/tags?post=155"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}