What are the differences between CMS and G1 garbage collectors?

What are the differences between CMS and G1 garbage collectors?

CMS (Concurrent Mark-Sweep) and G1 (Garbage-First) are both garbage collection algorithms in Java. CMS focuses on minimizing pause times by performing most of its work concurrently with the application threads, while G1 aims to provide predictable pause times by dividing the heap into regions and collecting them in a prioritized manner.

Which one is better for large applications?

For large applications, G1 is often preferred because it can handle large heaps more efficiently and provides more predictable pause times compared to CMS, which can suffer from longer pauses as the heap grows.

Are there any drawbacks to using G1?

Yes, G1 can have higher overhead due to its more complex algorithms and may require more tuning compared to CMS. Additionally, in some scenarios, it might not perform as well as CMS for smaller heaps.

How do I choose between them?

Choosing between CMS and G1 depends on your application's requirements. If you need low pause times and have a large heap, G1 is a better choice. If you have a smaller heap and can tolerate longer pauses, CMS might be sufficient.