How to diagnose Memory problem

Hi eduardo,

Your heap usage graph looks normal to me. I did not see memory leak and OOM error problem.

You can diagnose Memory problem either through a manual or automated approach. 

Manual approach

In the manual approach, you need to capture heap dump as the first step. Heap dump is a snapshot of memory, which shows all the objects in memory, values contained by those objects, and their references. You can capture heap dump using one of the 7 approaches given here . But an important criteria is: You need to capture the heap dump right before OutOfMemoryError is thrown. If you are going to capture a heap dump, after OutOfMemoryError has occurred, then leaking objects can get garbage collected, and it will become hard (or even impossible) to diagnose the problem. Once heap dumps are captured, you need to import the heap dumps from your production servers to your local machine. From your local machine you can use heap dump analysis tools like jHat, HeapHero, Eclipse MAT to analyze the heap dumps. Here is a video tutorial, which may assist you with it.

Automated approach

You can use root cause analysis tools like yCrash - which automatically captures application-level data (thread dump, heap dump, Garbage Collection log) and system-level data (netstat, vmstat, iostat, top, top -H, dmesg, kernel parameters…). Besides capturing the data automatically, it marries these two datasets and generates an instant root cause analysis report. Below is the report generated by the yCrash tool when the above sample program is executed:

Fig: yCrash tool pointing out the root cause of OutOfMemoryError

You can notice the yCrash tool precisely pointing out the root cause of memory leak. You can register here to get a 14 day trial of yCrash.