On 10/6/05, Phillip J. Eby <[EMAIL PROTECTED]> wrote: > At 10:09 PM 10/5/2005 -0700, Neal Norwitz wrote: > >The general idea is to allocate the stack in one big hunk and just > >walk up/down it as functions are called/returned. This only means > >incrementing or decrementing pointers. This should allow us to avoid > >a bunch of copying and tuple creation/destruction. Frames would > >hopefully be the same size which would help. Note that even though > >there is a free list for frames, there could still be > >PyObject_GC_Resize()s often (or unused memory). WIth my idea, > >hopefully there would be better memory locality, which could speed > >things up. > > Yeah, unfortunately for your idea, generators would have to copy off bits > of the stack and then copy them back in, making generators slower. If it > weren't for that part, the idea would probably be a good one, as arguments, > locals, cells, and the block and value stacks could all be handled that > way, with the compiler treating all operations as base-pointer offsets, > thereby eliminating lots of more-complex pointer management in ceval.c and > frameobject.c.
If we had these seperate stacks for each thread, would it be possible to also create a stack for generator calls? The current call operations could possibly do a check to see if the function being called is a generator (if they don't have a generator bit, could they, to speed this up?). This generator-specific stack would be used for the generator's frame and any calls it makes on each iteration. This may pose threat of a bottleneck, allocating a new stack in the heap for every generator call, but generators are generally iterated more than created and the stacks could be pooled, of course. I don't know as much as I'd like about the CPython internals, so I'm just throwing this out there for commenting by those in the know. _______________________________________________ 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
