Software Transactional Memory

thread lock 

def f(list1, list2):
    acquire_all_locks(list1.lock, list2.lock)
    x = list1.pop()
    list2.append(x)
    release_all_locks(list1.lock, list2.lock)


Software Transactional Memory (STM) 
def f(list1, list2):
    while True:
        t = transaction()
        x = list1.pop(t)
        list2.append(t, x)
        if t.commit():
            break

http://morepypy.blogspot.tw/2012/08/multicore-programming-in-pypy-and.html

http://morepypy.blogspot.tw/2011/06/global-interpreter-lock-or-how-to-kill.html

http://en.wikipedia.org/wiki/Hardware_transactional_memory

http://cs.brown.edu/courses/csci1610/papers/stm.pdf

http://morepypy.blogspot.tw/2011/08/we-need-software-transactional-memory.html