running functions

Tom Anderson twic at urchin.earth.li
Fri Nov 18 00:29:16 CET 2005


On Wed, 16 Nov 2005, sjdevnull at yahoo.com wrote:

> Gorlon the Impossible wrote:
>
>> Is it possible to run this function and still be able to do other 
>> things with Python while it is running? Is that what threading is 
>> about?
>
> Threading's a good answer if you really need to share all your memory. A 
> multiprocess solution is probably preferrable, though it depends on the 
> architecture.

I'm really curious about this assertion, which both you and Ben Finney 
make. Why do you think multiprocessing is preferable to multithreading?

I've done a fair amount of threads programming, although in java rather 
than python (and i doubt very much that it's less friendly in python than 
java!), and i found it really fairly straightforward. Sure, if you want to 
do complicated stuff, it can get complicated, but for this sort of thing, 
it should be a doddle. Certainly, it seems to me, *far* easier than doing 
anything involving multiple processes, which always seems like pulling 
teeth to me.

For example, his Impossibleness presumably has code which looks like this:

do_a_bunch_of_midi(do, re, mi)
do_something_else(fa, so, la)

All he has to do to get thready with his own bad self is:

import threading
threading.Thread(do_a_bunch_of_midi, (do, re, mi)).start()
do_something_else(fa, so, la)

How hard is that? Going multiprocess involves at least twice as much code, 
if not ten times more, will have lower performance, and will make future 
changes - like interaction between the two parallel execution streams - 
colossally harder.

tom

-- 
Remember when we said there was no future? Well, this is it.



More information about the Python-list mailing list