Question Re: Java is generating more heap dumps in Technology Q&A

Java is generating more heap dumps

Former Member — Mon, 06 Aug 2012 14:16:32 GMT

Hi Gurus,

Java system generating more dumps and file is filling completely. i saw some of the notes and threads but still not able to find problem and solution.

please help me to solve this issue.

under usr/sap/sid/instance/j2ee/cluster we have dumps folder is having around 76 gb and another folder apps is also having around 20 gb.

please help me clear this issue.

please find error screenshots.

Thanks in advance.

Venkat

Re: Java is generating more heap dumps

Former Member — Tue, 07 Aug 2012 09:59:30 GMT

Any help on this?

Re: Java is generating more heap dumps

duncanspeidel — Tue, 07 Aug 2012 17:28:34 GMT

Hi Venkat,

I would download the SAP Memory Analyzer and parse the heap dump. You can get more information from http://wiki.sdn.sap.com/wiki/display/Java/Java+Memory+Analysis. This should help you determine what is cause the dump and from there which steps to take.

Best regards,

Duncan

Re: Java is generating more heap dumps

Former Member — Wed, 08 Aug 2012 03:51:34 GMT

Thanks Duncan,

ok i will go through your link.

but i want stop generating this dumps immediate becuase am running short of space.

how can i stop generating this dumps?

Thanks,

Venkat

Re: Java is generating more heap dumps

Asha_Pillai — Wed, 08 Aug 2012 06:00:44 GMT

Hello Venkat,

Can you please check if all your JVM parameters are set correctly. They contain meny memory related parameters too.

Please refer to SAP notes 723909 or if you are using SAPJVM, please see note 1603093.

If you want to stop generation of heap dumps, please remove JVM parameter XX:+HeapDumpOnOutOfMemoryError, if set. Please refer to SAP note 1004255 for details.,

However, it is recommended to analyze these dumps so that you can find out the root cause before removing the parameter.

Regards,

Asha

Re: Java is generating more heap dumps

former_member215345 — Wed, 08 Aug 2012 09:48:47 GMT

You can delete the dump files from system to free space, this will not affect system operation.

Analyse the dump files to find exact cause of issue and prevent from further generation.

Regards,

Jayadeep.

Re: Java is generating more heap dumps

Former Member — Mon, 13 Aug 2012 10:17:15 GMT

Hi,

I have disabled parameter XX:+HeapDumpOnOutOfMemoryError but still it is generating some dumps at os level.

about these heap dumps i have gone through lot of notes but still am not able to solve this issue.

please guide me to right track.

Thanks in advance,

Venkat

Re: Java is generating more heap dumps

Former Member — Mon, 13 Aug 2012 15:52:31 GMT

Hi Venkat,

What system in your IX4 - BI/ECC ?

If you want to find the root cause you have to use any of the Heap Dump analyzer tools. You can also use Solution Manager.

As a workaround you can increase the server nodes.

Can you check the Garbage Collection history ?

Thanks,

Samik

Re: Java is generating more heap dumps

Former Member — Mon, 13 Aug 2012 16:01:19 GMT

Hello Venkat

As recommended by Samik above you should definitely analyze the heap dumps using a memory analyzer.

If you are still experiencing heap dumps then probably your heap size is too low. Have you tried to increase it ? what is it currently set at ?

Regards

Amit Padmawar

Re: Java is generating more heap dumps

hemanth2 — Tue, 14 Aug 2012 09:12:54 GMT

Hi Venkat ,

Hope you are doing good.

It seems that the engine has gone down due to severe memory restraints. When the engine goes down due to heap issues, there are 2 main steps inorder to resolve the case:

1) Make sure that the j2ee parameters and the server on the whole is configured correctly so that optimum performance can be obtained.

2) If 1) does not help, there may be a application causing a memory leak. We need to identify this and fix the issue.

Even if you remove the JVM parameters, there are OS-related options that maybe causing the dump. Please check the current settings of JAVA_DUMP_OPTS, JAVA_DUMP_TOOL and other parameters/ environment variables of the user <sid>adm. Incase of issues, kindly get in touch with the OS team.

Please consult the official documentation of your vendor, for example:

http://publib.boulder.ibm.com/infocenter/javasdk/tools/index.jsp?topic=/ com.ibm.java.doc.igaa/_1vg00014884d287-11c3fb28dae-7ffc_1001.html

There are several specific solutions mentioned:

- using DISABLE_JAVADUMP;

- using IBM_JAVADUMP_OUTOFMEMORY.

Thank you and have a nice day :).

_____________

Kind Regards,

Hemanth

Re: Java is generating more heap dumps

Former Member — Mon, 20 Aug 2012 11:47:59 GMT

Hi All,

still am not able to solve this dump issue, please help me to solve this.

here am attaching some error screens of logs, due to lomitations am not able to attach complete logs.

Thanks in advance,

Venkat

Re: Java is generating more heap dumps

Former Member — Mon, 20 Aug 2012 19:26:10 GMT

Hello Vankat,

This Out Of Memory issue is very common in SAP Java stack. I see your Java Heap memory is configured at 2048MB. As suggested above you an increase this to 3 GB as an interim solution (Please refer corresponding SAP Note for your operating system and JVM version to adjust other related parameters)

Also, how many server nodes do you have in your application server? And what type of system is this ? Did you try increasing server nodes ?

Regards,

Samik

Re: Java is generating more heap dumps

Former Member — Tue, 21 Aug 2012 08:20:28 GMT

Hi Samik,

It is BI system and only one server node is configured on this.

my OS is windows 2003 x64 bit and db is oracle 10g

JVM version is sap jvm5

Thanks in advance.

Venkat

Re: Java is generating more heap dumps

Asha_Pillai — Tue, 21 Aug 2012 11:49:14 GMT

Hello Venkat,

If you are using BI system, please increase the heap. The following note will be helpful

1044330 Java parameterization for BI systems

Regards,

Asha

Re: Java is generating more heap dumps

Former Member — Thu, 23 Aug 2012 08:17:12 GMT

Hi Asha,

i have increased heap memory to 3 gb but no use.

when i go and check NWA logs i observers there are some SLD error coming first then it is showing OOM error.

not sure will it related to OOM ?

Thanks in advance,

Venkat

Re: Java is generating more heap dumps

Former Member — Thu, 23 Aug 2012 08:57:27 GMT

Hello Raja,

Please gothrough SAP note 1634068 - .hprof files are hugely generated.

Regards,

Vishal

Re: Java is generating more heap dumps

Former Member — Thu, 23 Aug 2012 20:25:11 GMT

Hi Venkat,

Can you try analyzing the Heap Dumps to identify which application consuming all the memory ? You can use Eclipse Memory Analyzer. Check this link-

https://wiki.sdn.sap.com/wiki/display/Java/Java%20Memory%20Analysis

BI system Java application memory footprint can be higher, so you can think of increasing server nodes as a tuning measure if the dumps are appearing frequently.

Regards,

Samik

Re: Java is generating more heap dumps

Former Member — Mon, 17 Sep 2012 13:44:30 GMT

Hi All,

Finally am able to close this issue.

Actually issue is with SLD and it got resolved by applying latest patches for components J2EE ENGINE LM-CORE 7.11 and J2EE ENGINE FRAMEWORK

Check this note 1500151 - Out-of-memory error during system registration in SLD

Thanks to all for your time.

Venkat