Elasticsearch comes with good out-of-the-box Garbage Collection settings. So good in fact that the Definitive Guide recommends not changing them. While we agree that most use-cases wouldn’t benefit from GC tuning, especially when it turns out there simply isn’t enough heap, there are exceptions. We found that G1 GC, for example, works well on big heaps. This allows you to have less, bigger nodes, which in turn means less network traffic in a large cluster.