>> wouldn’t want the GC to run on that core

> We currently don't have an option for that other than going native.

You mean going manual memory management, I believe. Technically, JIT vs. ahead-of-time native vs. interpreted is orthogonal to manual memory management vs. GC. Yes, most JITs also have garbage collectors, but it's not necessarily the case.

But, your point does stand that when you really care about 99.99th percentile latency, you almost certainly need to go with static native compilation and manual memory management. The long-tail on JIT and/or most GCs is just too high.

The OS can cause 1ms pauses easily, so I would be wary whether 1ms is truly unacceptable. To consistently achieve it, not even native may be enough in itself, you have to circumvent the OS kernel as well.