> On July 15, 2019, 2:14 a.m., Benjamin Bannier wrote: > > src/master/master.cpp > > Lines 6255-6260 (patched) > > <https://reviews.apache.org/r/71008/diff/4/?file=2154545#file2154545line6255> > > > > It seems we only do this check to make sure we can access the config > > below which introduces quite some coupling. Is there a reason we couldn't > > grab the config outside the lambda and capture it instead (i.e., do we want > > to support mutable drain configs)? That would allow us to reduce coupling > > between `Slave::draining` and `markGone`.
This check is specifically to guard against an interleaving of the `RemoveSlave` and `MarkAgentDrained` registry operations. There are a variety of ways to trigger the `RemoveSlave`, one of which is shutting down the agent (SIGUSR1). So imagine the following sequence of events: 1) Agent sends the master a `UnregisterSlaveMessage`. 2) Master starts the `RemoveSlave` operation. 3) Final terminal ACK arrives at the master, which causes master to call `checkAndTransitionDrainingAgent` and `MarkAgentDrained`. 4) `RemoveSlave` completes. Master clears memory of that agent. 5) `MarkAgentDrained` completes. Master no longer knows about that agent and hits this LOG line. - Joseph ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/71008/#review216605 ----------------------------------------------------------- On July 11, 2019, 4:01 p.m., Joseph Wu wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/71008/ > ----------------------------------------------------------- > > (Updated July 11, 2019, 4:01 p.m.) > > > Review request for mesos, Benjamin Bannier, Benjamin Mahler, Greg Mann, and > Vinod Kone. > > > Bugs: MESOS-9814 > https://issues.apache.org/jira/browse/MESOS-9814 > > > Repository: mesos > > > Description > ------- > > This adds logic in the master to detect when a DRAINING agent can > be transitioned into a DRAINED state. When this happens, the new > state is checkpointed into the registry and, if the agent is to be > marked "gone", the master will remove the agent. > > > Diffs > ----- > > src/master/http.cpp b42ebb953e0510e83ec6bd041cbddbeb8f60067c > src/master/master.hpp 23dafe746b6f9b3d70ad7220f54c4d49068b8af8 > src/master/master.cpp 5247377c2e7e92b9843dd4c9d28f92ba679ad742 > > > Diff: https://reviews.apache.org/r/71008/diff/4/ > > > Testing > ------- > > TODO: Need to write some unit tests. I'll want to rebase onto the agent > changes so that there is more detectable stuff in the tests. > > > Thanks, > > Joseph Wu > >
