On Tuesday 27 June 2006 22:26, you wrote: > On 6/27/06, Tzahi Fadida <[EMAIL PROTECTED]> wrote: > > On Tuesday 27 June 2006 20:58, you wrote: > > > On 27/06/2006, at 15:03, Tzahi Fadida wrote: > > > > I am looking for an answer on python threads lock behaviour. > > > > So far, i have not managed to get an answer on #python, > > > > whatsup,#twisted,google... > > > > > > You probably need to revise your questions. > > > > Would like to say why? > > What do you mean by "threads lock behaviour"? It is unclear!
That's because there was no question until the second paragraph, sish... > > > > > If i have many threads running and there is a resource all want > > > > to posses using a lock, i.e., lock.acquire(). > > > > one obviously is going to posses the lock. > > > > My question is, when it is released using lock.release() which of > > > > the threads > > > > is going to acquire the lock? is it a random process or > > > > a FIFO order. I am trying to understand if starvation is possible > > > > in this particular instance. > > > > > > I think its undefined. > > > > > > > My other question, is what is more efficient: > > > > using locks, conditions, events, queues. i.e. i am building > > > > a server and i want to avoid unneccessary polling operations. > > > > > > The question is too general to get any useful answer. > > > > Sorry, but i don't think you are correct. > > I think he is. "unnecessary polling operations" have nothing to do with > locks, events, conditions and queues. You can implement busy waiting using > all those :-). > Also the fact that you did not get the answer says something, don't > you think so? No, it means that people does not know. I know (thru google browsing) though that python threads use pthreads. I asked because if python (or the underlying os or whatever goes on the lower levels) does not take care of threads locks to not get threads starved, i will have to take care of it myself using queues and conditions which i want to be sure is really neccessary first. Btw, a lock = Thread.allocate_lock() > > >For example, Event uses > > notifyAll while Condition uses notify etc... there is a difference, > > however there are other considerations like robustness etc... > > What do you mean "robustness and etc..."? I hope you will find some > information here: http://www.boost.org/doc/html/threads/faq.html. See 8 and > 11. Did not help. I am asking about threads in python not what threads or mutex are. > > > I am looking for an answer from someone who have experience > > with these. > > > > > Basically, avoid threads if you can - its hard to program and even > > > harder to test. It also does not scale well with Python because of > > > the GIL, unlike C, most of the time all your threads share the same > > > CPU. > > > > Basically what you are saying, python is a lame language since you cannot > > use threads with it. > > He did not said that. It sure sounded like that. -- Regards, Tzahi. -- Tzahi Fadida Blog: http://tzahi.blogsite.org | Home Site: http://tzahi.webhop.info WARNING TO SPAMMERS: see at http://members.lycos.co.uk/my2nis/spamwarning.html
