Look for UPDATE and ACKNOWLEDGE sections in https://github.com/apache/mesos/blob/master/docs/scheduler-http-api.md for semantics. Note that this doc for schedulers using the new HTTP API, but the semantics around updates are the same.
On Wed, Nov 18, 2015 at 4:41 AM, James Vanns <[email protected]> wrote: > Thanks very much for the prompt response, Tom. I shall go and read up on > reconciliation (I'd expected there to be something like this to read). And > to my knowledge, no I don't explicitly disable the implicit status > acknowledgement ;) > > Cheers, > > Jim > > > On 18 November 2015 at 12:24, Tom Arnfeld <[email protected]> wrote: > >> When you construct the scheduler, are you disabling implicit >> acknowledgements? >> >> https://github.com/apache/mesos/blob/master/include/mesos/scheduler.hpp#L373 >> >> I’d suggest having a read over this document, it explains some of this -> >> http://mesos.apache.org/documentation/latest/reconciliation/ >> >> a) Mesos may re-send messages if you don’t acknowledge them, and task >> status messages are guaranteed *at least once* >> c) If you disable implicit status acknowledgement, yep >> d) You should, they are guaranteed to be delivered *at some point* *at >> least once* by the slave / master. To keep your framework in sync with >> the cluster it is recommended to reconcile tasks often (as explained in the >> document above) >> e) http://mesos.apache.org/documentation/latest/reconciliation/ >> >> Hope that helps, and I think that’s all correct! The docs will be able to >> clarify better :-) >> >> On 18 Nov 2015, at 12:09, James Vanns <[email protected]> wrote: >> >> Hello list. >> >> We have an experimental framework (C++ API) based on Mesos 0.24 and we're >> seeing duplicate task status messages -- eg. 2 'FINISHED' messages for a >> single task. This may well be normal behaviour but I wasn't prepared for >> it. Could someone point me in the direction of a decent description on >> status updates/messages somewhere in the Mesos documentation? Or explain >> the following; >> >> a) Is this normal (it's not just the FINISHED state)? >> b) What might cause this behaviour (it's intermittent)? >> c) I do not explicitly acknowledge receipt of these messages - should I!? >> d) Should I treat these status update messages as reliable and robust!? >> e) Where can I learn more about this kind of internal detail? >> >> Cheers, >> >> Jim >> >> -- >> Senior Code Pig >> Industrial Light & Magic >> >> >> > > > -- > -- > Senior Code Pig > Industrial Light & Magic >
