heap-dump | 易学教程

How can I know whether a Java object is in tenure or eden space from heap dump

阅读更多关于 How can I know whether a Java object is in tenure or eden space from heap dump

问题 I have a Hotspot JVM heap dump and I tried to find out whether an object is live in tenure space, eden space, or survivor space, but I could not. Appreciate if someone can help me. 回答1: I don't think you can. From this forum post, sorry, bad news, the heap dump neither contains the info about the space the object is in Looking at the contents of the java heap dumps from this page seems to confirm that the heap dump does not contain generation info, HEAP DUMP BEGIN (39793 objects, 2628264

How to analyze heap data from .hprof file and use it to reduce memory leaks?

阅读更多关于 How to analyze heap data from .hprof file and use it to reduce memory leaks?

问题 In recent times, I have encountered java.lang.OutOfMemoryError exception while running an application. During one such instance, I was able to get the heap dump using jvisualvm . I am able to open the .hprof heap dump file obtained from the heap dump using NetBeans 8.1 IDE but I am not aware of how to analyze the data dump. I'd like to know how to read the dump file and take corrective actions to reduce the out of memory exception from an application perspective. 回答1: There are many ways to

How to collect heap dumps of any java process

阅读更多关于 How to collect heap dumps of any java process

问题 I am new to Heaps , can anyone suggest how can i take heap dump of any java process (like Jmeter). I read about jmap command , but i am not getting where and how to execute / write it (in eclipse or cmd). It might be a very basic question but still suggestions are requested.Can i download jmap.exe and jhat.exe from any where? Thank You 回答1: Here is the command: <JDK_HOME>/jmap -F -dump:live,format=b,file=<file_name.hprof> <process_id> You can mention the file location here in this command. 来源

Best method for inspecting Elastic Beanstalk JVM heap

阅读更多关于 Best method for inspecting Elastic Beanstalk JVM heap

问题 I'm need to get a JVM heap dump from an Elastic Beanstalk server, but the server doesn't have jcmd or jmap. Amazon doesn't natively install them with the JDK. Here's what's installed: [ec2-user@ip-x-x-x-x ~]$ sudo yum list installed|grep jdk java-1.7.0-openjdk.x86_64 1:1.7.0.111-2.6.7.2.68.amzn1 @amzn-updates java-1.8.0-openjdk.x86_64 1:1.8.0.101-3.b13.24.amzn1 @amzn-updates java-1.8.0-openjdk-headless.x86_64 1:1.8.0.101-3.b13.24.amzn1 @amzn-updates What's the best way to get a heap dump from

heapdump size vs hprof size

阅读更多关于 heapdump size vs hprof size

I recently made a heapdump in a hprof format when my jboss server was running with a xms of 4096m and xmx of 4096m and a permsize of 512m. The hprof file generated is over 5gb. When I load the heapdump in visualvm, mat analyzer or yourkit, I only see a total bytes of approximately 1gb. I've tried changed the reachability scope in yourkit but it does not show more than 1 gb. Any idea what this big difference in filesize vs displayed heapdump size can cause? ps: I'm using jdk1.6.0_23 Unfortunately I'm not allowed to submit screenshots here. On the filesystem the hprof size is of 5.227.659 kb and

How to analyze heap data from .hprof file and use it to reduce memory leaks?

阅读更多关于 How to analyze heap data from .hprof file and use it to reduce memory leaks?

In recent times, I have encountered java.lang.OutOfMemoryError exception while running an application. During one such instance, I was able to get the heap dump using jvisualvm . I am able to open the .hprof heap dump file obtained from the heap dump using NetBeans 8.1 IDE but I am not aware of how to analyze the data dump. I'd like to know how to read the dump file and take corrective actions to reduce the out of memory exception from an application perspective. There are many ways to find the root cause of a memory leak, like using a profiler such as JProfiler and simply applying what is

Android ==> Memory Analysing ==> Eclipse memory analyzer?

阅读更多关于 Android ==> Memory Analysing ==> Eclipse memory analyzer?

I need to check my application for memory leaks, i also need to see the memory allocation of my application. I downloaded and installed eclipse memory analyzer, and it looks like the first step is to open a heap dump. But what is a heap dump, how can i create a heap dump. And how exactly am i going to use this software, I did some googling but i couldn't find any useful information thanks When you debug your app, open DDMS in Eclipse. On the toolbar there is a heap dump button that you can use to generate a heap dump to view in Eclipse memory analyzer. This is only supported I think with the 1

memory analysis from eclipse ide does not list any local process id when acquire heap dump dialog is clicked

阅读更多关于 memory analysis from eclipse ide does not list any local process id when acquire heap dump dialog is clicked

问题 Using memory analyzer from eclipse ide (kepler), I'm trying to acquire heap dump from a locally running VM while an program is running, however acquire heap dump dialog does not list any pid to select. I try to configure hdrof jmap dump provider with -jdkhome C:\Program Files\Java\jdk1.8.0_05\bin but nothing happens. Any solution. Thanks. 回答1: remove bin from your path , It should be -jdkhome C:\Program Files\Java\jdk1.8.0_05 来源： https://stackoverflow.com/questions/24433668/memory-analysis

Number of String Objects on heap in JAVA-8

阅读更多关于 Number of String Objects on heap in JAVA-8

From this Number of String Objects on stack overflow,I came to know that if we do some thing like : String s = new String("ABC"); Then we have two objects one on heap that is String and one on constant pool that is "ABC" , But today I took the heap dump and found there are two objects on heap it self. I used MAT tool for the same please find the screen shot below. So my query is if there are two Objects on heap one of Char[] and other for String class and one on constant pool then thus this means that String s = new String("ABC") will create 3 objects in total. Holger There seems to be

Best method for inspecting Elastic Beanstalk JVM heap

阅读更多关于 Best method for inspecting Elastic Beanstalk JVM heap

I'm need to get a JVM heap dump from an Elastic Beanstalk server, but the server doesn't have jcmd or jmap. Amazon doesn't natively install them with the JDK. Here's what's installed: [ec2-user@ip-x-x-x-x ~]$ sudo yum list installed|grep jdk java-1.7.0-openjdk.x86_64 1:1.7.0.111-2.6.7.2.68.amzn1 @amzn-updates java-1.8.0-openjdk.x86_64 1:1.8.0.101-3.b13.24.amzn1 @amzn-updates java-1.8.0-openjdk-headless.x86_64 1:1.8.0.101-3.b13.24.amzn1 @amzn-updates What's the best way to get a heap dump from the JVM on Elastic Beanstalk? I have found you can install jmap by installing the correct package: