> It seems like a revisiting of the experience of the Self team between the second and third generation of Self VMs, though the underlying hardware might be just a little faster :) Do you think this tradeoff of peak performance vs interactivity is inherent in Truffle's approach? Or can Truffle realistically aim for the best of both worlds?

> One interesting aspect of the Self VM is that it can save the JIT generated native machine code together with the Self code in the image/snapshot, so that you can load a pre-warmed set of objects. Is that possible within the Truffle framework?

I completely agree. Mario Wolczko, who worked on the Self VM at that time, is part of the extended GraalVM team. So the knowledge and experience is there, it only has to be implemented. The GraalVM team is thinking about ways to support snapshotting and a couple of other things. Their profile-guided optimizations [1] is probably the closest to that and definitely a way into the right direction. So I'd say it is possible to make performance of GraalVM languages much more predictable, maybe to the extent that it doesn't matter anymore for interactivity.

[1] https://medium.com/graalvm/improving-performance-of-graalvm-...