Resulting in Full GC is generally due to the following situations:
1 ) older generation of lack of space
Try to make time to tune in the new generation of objects ( broken down into Eden and surviving area ) GC when recycled, so that objects in the new generation of multi survive for some time ( to increase the promotion of the new generation of memory or increase the threshold of old age ) and do not create and an array of objects too large to avoid direct in old age create an object on behalf of the
2 ) the new generation is set too small
First, the new generation GC number of very frequently, increasing consumption of the system; second leads directly into the large object older generation occupy elderly remaining space, induced Full GC
3). Cenozoic set too high
First, the new generation are too long, leading to the elderly generations too small (a certain amount of heap), and induce Full GC ; the second is the new generation GC consuming a significant increase
4). Survivor ( surviving area ) is set too small
Causes the object from Eden ( Eden ) directly reach older generations
5). Survivor is set too high
Resulting in Eden ( Garden of Eden ) is too small, increase the GC frequency
In general the new generation of the total heap 1/3 more appropriate
GC policy setting mode
1) certain priority may -XX: GCTimeRatio = n to set
2) the response speed priority may -XX: MaxGCPauseRatio = n to set