Generational Collections (Young and Old generation)

In generational collections technique the memory is divided into different memory pools as per the age of the objects. Some objects references stays alive for short duration they are called young objects and those objects which references stays alive for longer duration they are called old objects. So based on objects life span they are divided into Your Generation and Old generation objects.

Different algorithm used for different generations and each algorithm works based on the characteristics of that particular generation. Young generation algorithm are quite fast and frequent because young generation space is smaller and more objects exist without the references. While Old generation collection is less frequent and is managed by algorithm which is more space efficient, Old generation space is larger than the young generation.

In young generation when some objects alive for some number of collection cycles then they get promoted to the old generation.