Thanks for the responses, guys. That link of the 'detailed description' will be handy - I've not come across that before. I do now have another question though! Aren't these two a contradiction;
Alex; "you launch a task, before the method returns (say you do some blocking stuff after, like sync update zookeeper), you might get a statusUpdate() callback." Ben; "Methods will not be invoked concurrently, and each method must complete before the next is called." ?? Jim On 10 June 2015 at 02:22, Benjamin Mahler <benjamin.mah...@gmail.com> wrote: > If that's really what you're seeing, it is a bug and a very surprising > one, so please provide evidence :) > > See the "detailed description" here: > http://mesos.apache.org/api/latest/c++/classmesos_1_1Scheduler.html > > The scheduler driver will serially invoke methods on your Scheduler > implementation. Methods will not be invoked concurrently, and each method > must complete before the next is called. > > So, we recommend that you don't block inside the callbacks. Otherwise, > you're blocking the driver as well and your own ability to continue > processing callbacks. > > On Tue, Jun 9, 2015 at 8:58 AM, James Vanns <jvanns....@gmail.com> wrote: > >> Hi. I'm toying with the mesos scheduler (C++) API and running into >> unexpected race conditions. I have *not* synchronised access to attributes >> of my Scheduler-derived class. Is the mesos library code threaded and >> network communication asynchronous? What it *looks like* I'm seeing is my >> statusUpdate() callback being executed before the return of >> resourceOffers(). Naturally I call driver->launchTasks() inside >> resourceOffers(). This is intermittent but generally triggered by tasks >> that report status changes very quickly; eg. a task that fails instantly. >> >> Can anyone point me in the right direction of any online API docs that >> explain how callbacks are invoked? Distributed over a pool of worker >> threads? >> >> Also are the state transitions documented? Eg. >> mesos::TASK_STAGING -> mesos::TASK_STARTING -> etc. >> >> Cheers, >> >> Jim >> >> -- >> Senior Code Pig >> Industrial Light & Magic >> > > -- -- Senior Code Pig Industrial Light & Magic
