Collin Winter wrote: > Hey MA, > > On Mon, Feb 1, 2010 at 9:58 AM, M.-A. Lemburg <m...@egenix.com> wrote: >> BTW: Some years ago we discussed the idea of pluggable VMs for >> Python. Wouldn't U-S be a good motivation to revisit this idea ? >> >> We could then have a VM based on byte code using a stack >> machines, one based on word code using a register machine >> and perhaps one that uses the Stackless approach. > > What is the usecase for having pluggable VMs? Is the idea that, at > runtime, the user would select which virtual machine they want to run > their code under? How would the user make that determination > intelligently?
The idea back then (IIRC) was to have a compile time option to select one of a few available VMs, in order to more easily experiment with new or optimized implementations such as e.g. a register based VM. It should even be possible to factor out the VM into a DLL/SO which is then selected and loaded via a command line option. > I think this idea underestimates a) how deeply the current CPython VM > is intertwined with the rest of the implementation, and b) the nature > of the changes required by these separate VMs. For example, Unladen > Swallow adds fields to the C-level structs for dicts, code objects and > frame objects; how would those changes be pluggable? Stackless > requires so many modifications that it is effectively a fork; how > would those changes be pluggable? They wouldn't be pluggable. Such changes would have to be made in a more general way in order to serve more than just one VM. Getting the right would certainly require a major effort, but it would also reduce the need to have several branches of C-based Python implementations. -- Marc-Andre Lemburg eGenix.com Professional Python Services directly from the Source (#1, Feb 01 2010) >>> Python/Zope Consulting and Support ... http://www.egenix.com/ >>> mxODBC.Zope.Database.Adapter ... http://zope.egenix.com/ >>> mxODBC, mxDateTime, mxTextTools ... http://python.egenix.com/ ________________________________________________________________________ ::: Try our new mxODBC.Connect Python Database Interface for free ! :::: eGenix.com Software, Skills and Services GmbH Pastor-Loeh-Str.48 D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg Registered at Amtsgericht Duesseldorf: HRB 46611 http://www.egenix.com/company/contact/ _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
