Java-OOM整理

OOM整理

• • java.lang.OutOfMemoryError: Java heap space
    • memory leaks
• • java.lang.OutOfMemoryError: GC overhead limit exceeded
    • The java.lang.OutOfMemoryError: GC overhead limit exceeded error is displayed when your application has exhausted pretty much all the available memory and GC has repeatedly failed to clean it.
    • GC overhead limt exceed检查是Hotspot VM 1.6定义的一个策略，通过统计GC时间来预测是否要OOM了，提前抛出异常，防止OOM发生。Sun 官方对此的定义是：“并行/并发回收器在GC回收时间过长时会抛出OutOfMemroyError。过长的定义是，超过98%的时间用来做GC并且回收了不到2%的堆内存。用来避免内存过小造成应用不能正常工作。
    • 98% of the total time doing GC and when after the GC only less than 2% of the heap is recovered.
    • UseGCOverheadLimit
• • java.lang.OutOfMemoryError: Permgen space
    • the main cause for the java.lang.OutOfMemoryError: PermGen space is that either too many classes or too big classes are loaded to the permanent generation.
• • java.lang.OutOfMemoryError: Metaspace
    • jdk8
• • java.lang.OutOfMemoryError: Unable to create new native thread
    • Java application has hit the limit of how many Threads it can launch.
• • java.lang.OutOfMemoryError: Out of swap space?
    • The java.lang.OutOfmemoryError: Out of swap space? is thrown by JVM when an allocation request for bytes from the native heap fails and the native heap is close to exhaustion.
• • java.lang.OutOfMemoryError: Requested array size exceeds VM limit
    • Increasing the length of the array by one to Integer.MAX_VALUE-1 results in the familiar OutOfMemoryError:
• • Out of memory: Kill process or sacrifice child
    • The Out of memory: kill process or sacrifice child error is generated when the available virtual memory (including swap) is consumed to the extent where the overall operating system stability is put to risk. In such case the Out of memory killer picks the rogue process and kills it.

• References
  • Plumbr-OOM