Re: Concurrency via isolated process/thread

[Po Lu]

Ihor Radchenko <yantar92@posteo.net> writes:

> I imagine that the child Emacs will have a very limited obarray.
> If a symbol is not found in that process-local obarray, a query to
> parent Emacs process will be sent to retrieve the symbol slot values.

How will you retrieve the value of a symbol that does not exist in the
child process?  And what about the negative performance implications of
contacting another process to retrieve a symbol's value?  The object
will have to be copied from the parent, and the parent may also be busy.

Anyway, we already have sufficient mechanisms for communicating with
subprocesses.  If Emacs is to take any more advantage of SMP systems, it
must be properly interlocked, with multiple processors sharing the same
memory.  This lesson was learned decades ago with another program:
vmunix.