not getting java heap dump on outofmemoryerror:
Tried this (one.exe is my java rcp app):
one.exe -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=C:\Temp
but didn't help, the folder path is accessible. I even tried giving name like heap.hprof, but with no result. Can someone guide me here ?
Some thrown heap overflows are not real overflows, but are thrown directly after calculation. In fact, there is no overflow. such as DirectByteBuffer（use allocateMemory）
-XX:+HeapDumpOnOutOfMemoryError Command-line Option If you specify the -XX:+HeapDumpOnOutOfMemoryError command-line option, and if an OutOfMemoryError is thrown, the VM generates a heap dump
This above argument says it will generate HeapDump when OOM is thrown. If the JVM argument is passed to JVM and no heap dump got generated then it implies the application yet to suffer OutOfMemory condition.If you need confirmation then take native stderr log file of the application to check did application suffers any OOM? or include -verbose:gc jvm argument and collect verbose logs and check the last cycle of the GC to check the free bytes of the java heap.
Related
Getting java.lang.OutOfMemoryError : java Heap space on Jboss 7
The entry in jboss configuration is
set "JAVA_OPTS=-Xms1G -Xmx2G -XX:MetaspaceSize=96M -XX:MaxMetaspaceSize=2096M"
The Error was
java.lang.OutOfMemoryError: Java heap space
at java.util.Arrays.copyOf(Arrays.java:3332) [rt.jar:1.8.0_231]
at java.lang.AbstractStringBuilder.ensureCapacityInternal(AbstractStringBuilder.java:124) [rt.jar:1.8.0_231]
at java.lang.AbstractStringBuilder.append(AbstractStringBuilder.java:448) [rt.jar:1.8.0_231]
at java.lang.StringBuffer.append(StringBuffer.java:270) [rt.jar:1.8.0_231]
at java.io.StringWriter.write(StringWriter.java:112) [rt.jar:1.8.0_231]
at java.io.PrintWriter.write(PrintWriter.java:456) [rt.jar:1.8.0_231]
at java.io.PrintWriter.write(PrintWriter.java:473) [rt.jar:1.8.0_231]
at java.io.PrintWriter.print(PrintWriter.java:603) [rt.jar:1.8.0_231]
at java.io.PrintWriter.println(PrintWriter.java:756) [rt.jar:1.8.0_231]
at java.lang.Throwable$WrappedPrintWriter.println(Throwable.java:765) [rt.jar:1.8.0_231]
at java.lang.Throwable.printEnclosedStackTrace(Throwable.java:698) [rt.jar:1.8.0_231]
at java.lang.Throwable.printEnclosedStackTrace(Throwable.java:710) [rt.jar:1.8.0_231]
You are encountering OutOfMemoryError: Java heap space,in this case you dont have to increase MetaSpace. I will suggest you to increase heap allocation (Xms3G -Xmx3G). Make sure you have same values for Xms and Xmx. If you still encounter same issue with this then add -XX:+HeapDumpOnOutOfMemoryError option. This option will generate heap dump when OOM error occurs. You can analyze this heap dump through tools like eclipse mat to check which objects consume more memory and if there is any memory leak.
Depending on the application deployed on a JBoss, even 2 GB of a heap could be not enough.
Potential problems:
Xmx configuration is not applied (configuration is made in a wrong file)
The application just requires more heap
There is a memory leak in the application
If you run JBoss on Windows, set in standalone.conf.bat file in the JAVA_OPTS variable the following values -Xmx2G -XX:MaxMetaspaceSize=1G.
standalone.conf file is ignored on Windows and applied on *nix systems only.
Verify that these values are applied by connecting to the JVM using JConsole (that is a part of JDK) or JVisualVM.
Using these tools you can monitor heap usage and see if more heap is required.
If the heap size is big enough (e.g. 4+ GB) and heap still constantly grows while garbage collection (GC) doesn't free space, probably there is a memory leak.
For analysis add to the JAVA_OPTS the following flags: -Xloggc:gc.log -XX:+PrintGCTimeStamps -XX:+HeapDumpOnOutOfMemoryError.
With these flags JVM will log GC activity into the gc.log file where you can explicitly see how much space is freed after the GC.
If subsequent GC executions according to the log doesn't free any space, probably there is a memory leak and you should analyze a heap dump created manually using JVisualVM or created by JVM itself on OutOfMemoryError. Heap dumps can be analyzed using JVisualVM or Eclipse Memory Analyzer (MAT).
in case you use IntelliJ use the following image
inside VM option add what you need
java.lang.OutOfMemoryError: OutOfMemoryError usually means that you’re doing something wrong, either configuration
issue(where the specified heap size is insufficient for the application) or holding onto objects too long(this prevents the objects from being garbage collected), or trying to process too much data at a time.
Possible Solutions:
1) Try setting "JAVA_OPTS=-Xms1G -Xmx1G -XX:MaxPermSize=256M " to maximum value and restarting your server.
2) Check your code for any memory leak. Use some heap dump reader to check the same. (There are multiple plugins available for IDE's like Eclipse, IntelliJ, etc)
3) Check your code(90% of the times issues are in the code): Check if you are loading excess data from a database or some other source into your heap memory and if it's really required. If you are calling multiple web-services and multiple DB Read-only operations cross-check the db query(If Joins are perfectly used with right where clauses) and amount of data returned from db query and web service.
4) If the issue is due to some recent code change, then try to analyze the same.
5) Also, check if cache and session elements are cleared once used.
6) To be sure if the issue is not due to Jboss, you can run the same code on some other server for testing purpose(Tomcat, Websphere, etc)
7) Check Java documentation for more understanding on Out of memory error: Documentation Link
Make sure you have provided enough space in your standalone.conf file inside bin directory
JAVA_OPTS="-Xms512m -Xmx1024m -XX:MetaspaceSize=512M -XX:MaxMetaspaceSize=1024m -Djava.net.preferIPv4Stack=true"
You should have to increase MaxMetaSpaceSize upto 1024m and MetaspaceSize to 256m hope it will works.
Try also to monitor your process , try to run jvisualvm ( is included into the jdk ) and a UI will open , from there you will be able to get a lot of info.
Hope this help you.
Usually, this error is thrown when there is insufficient space to allocate an object in the Java heap. In this case, The garbage collector cannot make space available to accommodate a new object, and the heap cannot be expanded further.
Please do the below possible steps for fixing java.lang.OutOfMemoryError.
Step 1: Check JBoss configuration settings. The setting depends on your system configuration, java version and JBoss version. Check configuration here.
Step 2: Check Heap dump settings here.
Step 3: Java code/ Library problem.
Analyze your memory here And Jboss memory profiler.
Other causes for this OutOfMemoryError message are more complex and are caused by a programming error.
My Jenkins is running in an Ubuntu server instance. At the completion, when a Checkmarx report is being generated, I get a Java heap space issue as shown in the screen shot:
Can someone help me how to increase Java heap space in Checkmarx?
To read the Atlassian KB article "Scan Fails with Java Heap Space Exception" an account seems to be necessary.
Read more about what is OutOfMemoryError here. Jenkins itself run as a Java process and if your Jenkins job is also a java process, both of them could cause out of memory Error.
By seeing the log it looks like your job is running into the error. So read also about How to set a JVM option in Jenkins globally for every job?.
Edit: If your Jenkins process itself running into OutOfMemoryError, then refer to Increase heap size in Java on how to increase the JVM heap size for Java processes.
Normally -Xmx2048M is used to specify the max heap size for a java process, in my example i am setting it to 2048 MB. Depending on your configuration, you specify this value in different ways.
In my Java application a heap dump file gets generated when I read from the OutputStream of a script. I am sure about a memory leak in my application. But even after the heap dump got generated, the thread which is causing the memory leak is not coming out. I am not catching Throwable, Exception, Error etc in the run method.
I want to know when the Heap Dump file will get generated when I have not specified any special VM argument like
-XX:+HeapDumpOnOutOfMemoryError
AFAIK, heapdumps are only automatically generated if you specify that option, at least in Oracle's JVM (don't know about the others, but I doubt they do it automatically).
In most cases you have to trigger heap dump generation manually.
There are also ways to programmatically create a heap dump, but those are JVM specific and depend on how and when the programmer calls them. If that option is used then you'd have to look for that as it could be anywhere.
My application is deployed on a cluster environment. Recently the server went down with the following stacktrace. It doesn't seem to be coming from the code. It was running all right until recently when this error pop up. No major changes were made to the server. Can someone advise?
java.lang.OutOfMemoryError: Java heap space
at java.lang.AbstractStringBuilder.<init>(AbstractStringBuilder.java:44)
at java.lang.StringBuilder.<init>(StringBuilder.java:69)
at java.io.ObjectStreamClass$FieldReflectorKey.<init>(ObjectStreamClass.java:2106)
at java.io.ObjectStreamClass.getReflector(ObjectStreamClass.java:2039)
at java.io.ObjectStreamClass.initNonProxy(ObjectStreamClass.java:586)
at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1552)
at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1466)
at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1591)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1299)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:348)
at weblogic.utils.io.ChunkedObjectInputStream.readObject(ChunkedObjectInputStream.java:195)
at weblogic.rjvm.MsgAbbrevInputStream.readObject(MsgAbbrevInputStream.java:565)
at weblogic.utils.io.ChunkedObjectInputStream.readObject(ChunkedObjectInputStream.java:191)
at weblogic.rmi.internal.dgc.DGCServerImpl_WLSkel.invoke(Unknown Source)
at weblogic.rmi.internal.BasicServerRef.invoke(BasicServerRef.java:589)
at weblogic.rmi.internal.BasicServerRef$1.run(BasicServerRef.java:479)
at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:363)
at weblogic.security.service.SecurityManager.runAs(Unknown Source)
at weblogic.rmi.internal.BasicServerRef.handleRequest(BasicServerRef.java:475)
at weblogic.rmi.internal.BasicServerRef.access$300(BasicServerRef.java:59)
at weblogic.rmi.internal.BasicServerRef$BasicExecuteRequest.run(BasicServerRef.java:1016)
at weblogic.work.SelfTuningWorkManagerImpl.schedule(SelfTuningWorkManagerImpl.java:126)
at weblogic.rmi.internal.BasicServerRef.dispatch(BasicServerRef.java:321)
at weblogic.rmi.internal.BasicServerRef.dispatch(BasicServerRef.java:918)
at weblogic.rjvm.RJVMImpl.dispatchRequest(RJVMImpl.java:1084)
at weblogic.rjvm.RJVMImpl.dispatch(RJVMImpl.java:1001)
at weblogic.rjvm.ConnectionManagerServer.handleRJVM(ConnectionManagerServer.java:240)
at weblogic.rjvm.ConnectionManager.dispatch(ConnectionManager.java:877)
at weblogic.rjvm.MsgAbbrevJVMConnection.dispatch(MsgAbbrevJVMConnection.java:446)
at weblogic.rjvm.t3.MuxableSocketT3.dispatch(MuxableSocketT3.java:368)
at weblogic.socket.AbstractMuxableSocket.dispatch(AbstractMuxableSocket.java:383)
at weblogic.socket.SocketMuxer.readReadySocketOnce(SocketMuxer.java:872)
You are running out of memory, which suggests one of the following:
you need to give your process more memory (with the -Xmx java command line option); or
you have a memory leak
Without more information, it's hard to say which is the case. The stack trace for an OutOfMemoryError is rarely useful, as it only shows the point at which heap was exhausted; it doesn't show you why your heap is being filled up.
The answer by Simon Nickerson is correct
Just to add, your stack trace begins from weblogic.socket.SocketMuxer.readReadySocketOnce which is the internal weblogic class that accepts incoming requests. So this means the server is not having enough memory to accept requests also.
Are you using the JRockit JVM? If you are you can use JRockit Mission Control and monitor the Java heap usage. You can also use the JRockit Flight Recorder to record JVM events for offline analysis. There is an Oracle webcast on this here: http://www.vimeo.com/22109838. You can skip to 4:54 which is where the overview of JRockit, WLDF and JRF starts.
Keep in mind that when the heap is full it is the NEXT operation that fails with the OutOfMemory Exception, and therefore this stack trace may not indicate any cause of the failure. This simply indicates that when this code ran there wasn't enough heap, not that this code caused the heap to fill up.
** Edits...
Clearly the server is out of memory - at the time of this specific operation. The question is... why? This stack trace doesn't tell you -why- it just indicates that whatever was happening at the time could not complete because there was not enough memory available at that time. This does not mean that it is the cause of the problem.
Sure, you can add more memory but that may not fix the problem - it may only take longer for it to appear.
set catalina.sh/bat
find set JAVA_OPTS=%JAVA_OPTS%
what ever your RAM - adjust but don't give above half of RAM
set JAVA_OPTS=%JAVA_OPTS% %LOGGING_CONFIG% -server -Xms512M -Xmx512M -XX:MaxPermSize=256M
It means that the JVM has run out of all the memory that has been allocated to it. You can change the amount of memory allocated for use by your JVM using the -Xms and -Xmx command line parameters.check the root cause here
OutOfMemoryError in Java is a subclass of java.lang.VirtualMachineError and JVM throws java.lang.OutOfMemoryError when it ran out of memory in heap. OutOfMemoryError in Java can come any time in heap mostly while you try to create an object and there is not enough space in heap to allocate that object
I start my java code (1.6.0_16 in Vista) with the following params (among others) -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=../logs. I run the code and I can see in the logs there are two OOM.
The first one I know cause I can see in the stdout that the hprof file is being created:
java.lang.OutOfMemoryError: Java heap space
Dumping heap to ../logs\java_pid4604.hprof ...
Heap dump file created [37351818 bytes in 1.635 secs]
And then, towards the end of the code I get another OOM, I capture this, but I don't get a second hprof file created. Anybody knows why is that?? Is it because I have captured the OOM exception?
I wouldn't try to recover from an OutOfMemoryError as some objects might end up in an undefined state (just thinking about an ArrayList that couldn't allocate its array to store date for instance).
Regarding your question, I'd suspect that -XX:+HeapDumpOnOutOfMemoryError is only creating a single dump intentionally to prevent multiple heap dumps: just think about several threads throwing an OOME at the same time, causing a heap dump for each thrown exception.
As a summary: don't try to recover from OOME and don't expect the JVM to write more than a single heap dump. However, if you still feel the need to generate a heap dump, you could try to manually handle an OOME exception and call jmap to create a dump or use "-XX:+HeapDumpOnCtrlBreak" (not sure though, how to simulate CtrlBreak programmatically).
Out of memory generates only one dump-file on the first error. If you want to get more you can try jmap or keep jconsole on the jvm (version 6) then you can after everything crashed i.e in the morning create your own dump from jconsole (or your analyser tool of choice).
More on the dumping subject can be read in Eclipse MemoryAnalyser.