Hi Robert, I know you would suggest this solution :). I prefered to use the option one thread + list of fetch. Because i want to be able to destroy a thread even if not finished, and it's easy to manage one thread + fetch list per 'class instance' even if it's consume more thread. It's not thread that are consuming cpu.
I did not test on windows, the stuff about join() and detach(), so i guess it would be good to have an advise about it. Cheers, Cedric -- +33 659 598 614 Cedric Pinson mailto:[email protected] http://www.plopbyte.net On Mon, 2009-11-30 at 17:23 +0000, Robert Osfield wrote: > Hi Cedric, > > Thanks for the explanation. In terms of implementation rather than > create on thread to create a player I would create one or more > osg::OperationThread and attach a single shared OperationQueue > between them, and then just add a custom osg::Operation to the queue > when I want an operation done. Your player loading would then be done > within a subclass of osg::Operation. You could even do the database > loading this way too to enable multi-threading loading. When the > OperationQueue is empty the threads just go to sleep and don't consume > any CPU resources. > > What you are doing is still valid though, and I believe that once an > OpenThreads::Thread is destructed and it's associated thread destroyed > all the OS resources associated with it should be properly cleaned up > - it shouldn't be up to the app developer to go call join or detach. > One thing we could do is add the extra calls to Thread::cancel() to > make to it properly clean up. In the past we've used join() but I > recall a report of problems with join() on some system - this is going > back nearly a decade though... and I can't recall the specifics of the > problem with join(). Lots of happened since then, including likely > fixes to various Pthread join implementations so it's probably safer > for us to add it these days. > > Any thoughts from the community? > > Robert. > > On Mon, Nov 30, 2009 at 2:32 PM, Cedric Pinson > <[email protected]> wrote: > > Hi Robert, > > > > Ok in my game when i load a ressource i do it in a thread. I dont > > allocate a thread pool. i just create one thread per load sequence. For > > example when i create a player i craete one thread with a list of files > > to load. During the game a player can arrive and leave. So there will be > > a lot of thread creation and destruction when the game run a long time. > > It's a simplified view but it's the idea. > > > > Without my modification in my code when i created a thread load data and > > delete it. The thread resource was not clear, it's still valid even if > > finish. So after one day of game running i had 3Gb of finished thread > > and deleted but without ressources released. > > > > http://www.kernel.org/doc/man-pages/online/pages/man3/pthread_detach.3.html > > http://www.kernel.org/doc/man-pages/online/pages/man3/pthread_join.3.html > > > > > > I tested two behaviours with join and detach. Both work: > > If i call detach after the creation of my thread the resources are released > > when deleted. > > And if i call join when the thread is finish the resources are also > > released. > > > > http://www.kernel.org/doc/man-pages/online/pages/man3/pthread_create.3.html > > in the notes section they explain the stuff about the resources. > > > > I give pointer to doc only because it explains better than i could, I think > > you already know those doc. > > > > > > > > to do the test do something like that: > > > > int main(int argc, char** argv) > > { > > { > > create 200 threads > > run them > > when all are finished delete them > > } > > sleep( 1000); > > // check your system memory and virtual memory > > return 0 > > } > > > > > > I am not sure if we need to fix this inside osg, i mean calling detach do > > what is expected. > > Just user must be aware about this behaviour. > > > > I hope i explained correctly > > > > Cheers, > > Cedric > > > > -- > > +33 659 598 614 Cedric Pinson mailto:[email protected] > > http://www.plopbyte.net > > > > > > On Mon, 2009-11-30 at 10:47 +0000, Robert Osfield wrote: > >> HI Cedric, > >> > >> On Sun, Nov 29, 2009 at 11:02 PM, Cedric Pinson > >> <[email protected]> wrote: > >> > Ok reading the code and the doc of pthread, in order to have the > >> > ressource freed at the end of the thread, i must call detach(). now i > >> > have my memory back > >> > > >> > maybe it could help for others that create thread in application on a > >> > long period > >> > >> Could you explain a bit more how you are using threads/how you are > >> finishing them/destructing. > >> > >> Is there something missing from OpenThreads Thread destruction? > >> > >> Robert. > >> > > > _______________________________________________ > osg-users mailing list > [email protected] > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >
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