Gavin Kistner schrieb:
> 2) No, I doubt that the placement of a single boolean assignment made
> any measurable difference either way. My point with this thread
> (which has been answered) was simply to find out if Ruby had any
> similar things to keep in mind that would flow down to the
> instruction pipeline architecture. The placement of that assignment
> in the C++ code
>

I just searched google for super-scalar optimizations regarding
interpreters and found a paper about java bytecode-interpreters:
http://www.csc.uvic.ca/~csc586a/papers/p58-ogata.pdf

It seems, that the frequent memory access of interpreters prevent
super-scalar processors from branch-predicting and parallel-execution.

So you may assume, that almost no parallel execution happens in a ruby
script execution.

Besides that, I was always wondering, if there are performance issues
with procs. Given the fact, that they hold a reference to the c-stack,
maybe a proc call would result in some kind of stack restoring. This is
also the reason for the enormous memory consumption of continuations,
which store the whole c-stack(about 60kb).