Java Heap Dumps Creations

Hi

There are frequent heap dumps are getting created in Integration server (9.5.1). We are not yet able to trace yet any errors, logs . Can any one please let me know if faced same issue ever. And there are no out of memory errors too.

Regards
MSK

Is the IS responding irrespective of the thread dumps you see?

I would suggest if you see it frequently which is not unusual, please open a incident with SAG and troubleshoot.

If your IS still up, please invoke the diagnostic data and send it to them.

HTH,
RMG

Hi RMG,

There is no weird IS behaviour due these dump creations and there are no traces as i mentioned before. But, FYI the IS has to carry large volume of iDOCS of max size 5-7 MBs. But, I am not sure this causing the issue. Recently I have increased the IS heap size to 6 GB. I wanted to debug this in depth before raising a ticket. Note : dumps are of size 8-10 GB each.

Regards
MSK

In this specific case, you gather logs for a complete week, perform analysis to see any clue. Though everything is okay, its better to reach SAG to know the reason for this behaviour.

Thanks,

Hi Mohamad,

did you have a look at the error log file which is written additionally to the core dump?

Are there any messages in the server log or error log of the IS?

You can try to enable the RFC Tracing for the RFC Connection to see what happens on the transport layer.

What is your Fix-Level for SAP-Adapter and which version of the JCo-Libs are you using?

From time to time take a thread dump to see what happens inside the JVM.

Regards,
Holger

Hi,

There is nothing much in logs (error/server/RFC). And we can’t increase the loging for long time and data volume is also huge. I did check on fixes, we are in SAP SAP_7.1_Fix10 for 9.5.1. This seems fine.

Let me do more analysis here.

MSK

Hi Mohamad,

can you share the About-page of your SAP-Adapter?

There are limitations on which version of JCo 3.x will work with which Fix of SAP-Adapter 7.1.
This might lead to Memory Leaks et al causing the Heap Dumps.

Latest Fix for SAP Adapter 7.1 is Fix14 which is the minimum requirement when using JCo 3.0.13 and newer according to Readme for the Fix.

Fix15 is planned for December.

Regards,
Holger

I agree with Holger , please check the fix levels and try to be on the up to date version’s which may resolve many of the issues (of course with proper testing)

HTH,
RMG

If you’re getting lots of heap dumps, then that is an indication that you’re maxing out your heap. It could be because of a memory leak or very large documents being loaded into memory at once. You can analyze those heap dumps by using something like MAT: https://eclipse.org/mat

With heap dumps of that size though, using MAT may be a bit of a challenge. You will need a client computer that has enough physical memory and you will need to change the default settings for MAT so its heap is large enough to process your heap dump. Alternatively, you could lower your JVM heap size temporarily so that the heap dumps are smaller, which should make it a bit easier/faster to transfer and analyze using MAT.

Percio