On Mon, Mar 19, 2018 at 7:33 AM, John Spray <jspray@xxxxxxxxxx> wrote: > Hi all, > > I was looking at places in ceph-mgr where we send a command from a > module, and then want to proceed with some logic that involves reading > the osdmap (there is a local copy in the manager, maintained by > Objecter). > > I had been thinking that we should include cluster map epochs in the > MMonCommandAck messages so that the client can (optionally) wait for > that latest OSDMap before it considers the command complete. > > Then I thought, maybe this isn't necessary at all, because the mons > would be doing the check_subs() etc calls before they actually respond > to commands, so clients would always get their updated maps before > seeing a command response message. > > So: mon experts, what do you think? Is it safe to assume that clients > will get their subscription updates before a command completion (even > in the case of commands being forwarded)? Or do we maybe need a > little bit more logic on the client side in the manager? I would expect the order of op replies versus subscription fulfillment messages to be an implementation detail, even if we do currently spool off new map subscription requests inline with committing them. (I don’t know at all if that’s the case.) -Greg -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
