Mat Parse Dump Long

If you want to read an alternative dump one has to start mat with the system property mat hprof dump nr index.

Mat parse dump long.

Illegal record length 3 801 619 192 at byte 3 783 934 196 for record type 1 the dump was generated with jmap f dump file on a linux machine running java version 1 6 0 31 java tm se runtime environment build 1 6 0 31 b04. The snapshot mainly consists. Go to eclipse mat home directory and edit memoryanalyzer ini file. The eclipse foundation home to a global community the eclipse ide jakarta ee and over 350 open source projects including runtimes tools and frameworks.

However trying to get the ui to run remotely is very painful. There are situations in which it s necessary to set xmx parameter value above the size of parsed heap dump file. Change xmx parameter value to appropriate one. A heap dump is a snapshot of all the objects that are in memory in the jvm at a certain moment.

Mat requires almost as much heap as the dump file itself. Fortunately there is a script that comes with mat to parse the the heap dump and generate html reports without ever having to launch eclipse. If you try to open 4gb hprof and get java heap space error you should try to raise xmx above 4gb. But parseheapdump script that comes along with mat does the job of parsing and creating indices in a short span of time.

Launching eclipse and updating the ui is an extra load on the jvm that is already busy analyzing a 30g heap dump. Eclipse memory analyzer tool mat is by far the best tool to analyze java heap dumps. They are very useful to troubleshoot memory leak problems and optimize memory usage in java applications. All that you have to do is to copy the generated indices and the dump file to your local machine and open it with mat.

By default mat takes the first heap dump. A heap dump is a snapshot of the heap memory of a java process at a given time. Heap dumps are usually stored in binary format hprof files. The parser extension point for parsing the new format the trigger heap dump extension point to enable the user to trigger a heap dump from the vm with mat when mat reads a new heap dump the parse method in the class snapshotfactoryimpl will be called.

In this article we ll show different ways to capture a heap dump in java. Memory analyzer 1 2 and earlier has no ui support to decide which heap dump to read.