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 <[email protected]> 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 >
