On Fri, Nov 27, 2009 at 8:57 AM, OkaMthembo <zebr...@gmail.com> wrote: > Thanks, i must admit the concept of the GIL is cloudy to me - for example, > if the python interpreter on a single machine is > handling one process and locks until it is done, then on to the next one, > and so on - isn't that what causes speed issues?
A single interpreter runs in a single process. Within that process, only one thread can be interpreting Python byte codes at one time. If a thread is blocked, for example waiting for I/O, another thread can run. Some C extensions release the GIL so other threads can run concurrently. > I was wondering why python can't implicitly handle multiple processes at > once by using all machine cores (have many threads, each > invoking the interpreter and handling a process). Because explicit is better than implicit? The multiprocessing module allows you to control multiple processes from Python and do pretty much what you describe above - a Python main program can create multiple processes, each running a separate interpreter, all working on a single problem. > Maybe i should get up to speed on threads first to get the bigger picture? At least make sure you understand the difference between threads and processes. Kent _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
