I'm not sure what the value of a context cache is for a modern
designed high performance VM. Any VM that does dynamic inlining
like Self may be able to reduce the number of method calls to the
point were a context cache isn't worthwhile. After all all common
calls should be inlined.

However if you could inline the contexts as they were faulted into the
context cache then build uninlined contexts as they are faulted out it
may be possible to have very cheap de-optimization. If inlined
contexts are full objects then to remove the compiled code requires
allInstances which does a full memory scan.

Bryce