Do I need a lock here?

jasiu85 jasiu85 at gmail.com
Mon Oct 27 05:02:12 EDT 2008


Hey,

Please take a look at the code of the two threads below:

COMMON_DICT = {}

def thread_1():
    global COMMON_DICT
    local_dict = prepare_dict()
    COMMON_DICT = local_dict

def thread_2():
    global COMMON_DICT
    local_dict = COMMON_DICT
    use_dict(local_dict)

Do I need a lock to protect the COMMON_DICT dictionary? AFAIK bytecode
operations are atomic and in each thread there's only one crucial
bytecode op: STORE_NAME in the first thread and LOAD_NAME in the
second one. So I suspect that everything will work just fine. Am I
right?

Regards,

Mike



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