> On June 23, 2017, 7:21 p.m., Adam B wrote: > > src/slave/slave.cpp > > Lines 1405-1407 (original), 1405-1408 (patched) > > <https://reviews.apache.org/r/60405/diff/2/?file=1761692#file1761692line1405> > > > > If this agent has refinements, and we send post format to an old > > master, will the old master safely reject the registration, crash and burn, > > or something in between? > > Neil Conway wrote: > The master will basically consider the resources to be unreserved; > because the master and agent will have inconsistent views of the resource > state at the agent, this will cause problems. > > Since you need a new master to create reservation refinements in the > first place, you can only arrive in this situation by: > > Upgrading master > Upgrading agent > Creating res refinement > Downgrading master > > Which arguably falls under the "don't downgrade if you are using new > featues" bucket. But yes, this is certainly unfortunate. Hard to prevent > without introducing something similar to master capabilities, which we > definitely need (MESOS-5675). I'll drop this issue for now, since AFAIK > there's not much we can do to improve this in the short term.
Sounds good. Thanks for the explanation. At least we don't crash.. > On June 23, 2017, 7:21 p.m., Adam B wrote: > > src/slave/slave.cpp > > Line 1408 (original), 1412-1414 (patched) > > <https://reviews.apache.org/r/60405/diff/2/?file=1761692#file1761692line1412> > > > > We could at least log an INFO/WARN if we aren't able to downgrade, and > > still send it anyway. > > Neil Conway wrote: > Hmm, not sure a warning/log is warranted here. In the common case > (refined reservation, >= 1.4 master, >= 1.4 agent), we will fail to downgrade > the resources, but that is fine and expected. Should we really be cluttering > the logs with this information? Good point. Don't want to over-log in the common case. Would be nice if we had master capabilities so we only had to log failure-to-downgrade when we're (re)registering with an old master. - Adam ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/60405/#review178834 ----------------------------------------------------------- On June 24, 2017, 10:30 a.m., Neil Conway wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/60405/ > ----------------------------------------------------------- > > (Updated June 24, 2017, 10:30 a.m.) > > > Review request for mesos, Adam B and Michael Park. > > > Repository: mesos > > > Description > ------- > > Documented resource format in agent <-> master protocol. > > > Diffs > ----- > > src/messages/messages.proto 2c086263fdcee4d54a76a61379c2d4dba5271d23 > src/slave/slave.cpp f808458849bb9667a91abe18868751d377d36e0c > > > Diff: https://reviews.apache.org/r/60405/diff/3/ > > > Testing > ------- > > > Thanks, > > Neil Conway > >
