threading and multicores, pros and cons

[Paul Rubin]

"sjdevnull at yahoo.com" <sjdevnull at yahoo.com> writes:
> > question of library functions--you could certainly write JNI
> > extensions for that stuff [access to mmap, etc.]
> Sure.  If you're writing extensions you can work around the GIL, too.

I don't think that's comparable--if you have extensions turning off
the GIL, they can't mess with Python data objects, which generally
assume the GIL's presence.  Python's mmap module can't do that either.

> Up through 1.3/1.4 or so they were pretty staunchly in the "threads
> for everything!" camp, but they've added a select/poll-style call a
> couple versions back.  That was a pretty big sticking point previously.

They've gone much further now and they actually have some STM features:

  http://www-128.ibm.com/developerworks/java/library/j-jtp11234/