I wanted to add a word of warning that switching to G1 won't necessarily give you breathing space. In fact, I know it definitely won't.
In your original post, it looked like the node had a very small heap (2GB). In my experience, you need to allocate at least 8GB of memory to the heap for production workloads. You might be able to get away with 4GB for apps with very low traffic but 8GB should really be the minimum. For real production workloads, 16-24GB is ideal when using CMS. But once you're in the 20GB+ territory, I recommend switching to G1 since it performs well for large heap sizes and it is the collector we recommend for heaps between 20-31GB (32GB heap has less addressable objects than 31GB). It's really important to note that G1 doesn't do well with small heap sizes and you're better off sticking with CMS in that case. As always, YMMV. I'm sure others will chime in with their own opinions/experiences. Cheers!
