> As I understand TTL nodes, you want to have them when you don't want to have > sessions
That’s not the only use case. For example, here at Elasticsearch we have a need for a semi-persistent node. It’s a node that lasts for about an hour. Whether or not there is a session is irrelevant. I ended up adding a recipe to Curator for it but it would be much nicer to have direct support in ZK for this. Again, I think you’re conflating the session issue with TTL nodes. They are different topics. -Jordan > On Aug 30, 2016, at 12:23 PM, Flavio Junqueira <f...@apache.org> wrote: > > As I understand TTL nodes, you want to have them when you don't want to have > sessions. I find it odd that you still need to create a session when you > choose to use TTL nodes to avoid sessions. It is correct that you can create > session/create TTL/close session in this order, but again, if you're trying > to avoid sessions, then it doesn't seem to be very appealing to use TTL nodes > this way. > > In any case, I need to go through the e-mail thread that Camille pointed out. > There is possibly some insight there that I'm missing. > > -Flavio > >> On 30 Aug 2016, at 14:21, Jordan Zimmerman <jor...@jordanzimmerman.com> >> wrote: >> >> Yes, you need a session to create the TTL node. I believe discussion about >> needing a session to create the node is beyond the scope of this issue and >> should be addressed by a new Jira issue. It doesn’t affect the utility of >> TTL nodes that you must first have a ZK session. Users who no longer want a >> session can merely close the ZK handle after creating the TTL node. >> >> -Jordan >> >>> On Aug 30, 2016, at 7:41 AM, Flavio Junqueira <f...@apache.org> wrote: >>> >>> >>>> On 29 Aug 2016, at 19:51, Jordan Zimmerman <jor...@jordanzimmerman.com> >>>> wrote: >>>> >>>>> On the server side, we already have a mechanism to expire sessions, do we >>>>> a separate scheme to expire TTL nodes or can we use the same mechanism? >>>>> Does it make sense to consider a TTL node as a degenerate case of a >>>>> session in which I have a single ephemeral node? My recollection is that >>>>> it currently uses the container manager instead. >>>> >>>> The TTL implementation I did takes advantage of the Container node >>>> feature. A TTL node is a variation of a container node. It doesn’t require >>>> a session (like any persistent node). >>>> >>> >>> It doesn't require a session, but the client has no way to create such a >>> TTL node without creating a session first, right? You need the zk handle, >>> which has a session associated, to create a TTL node as I understand it. >>> >>> -Flavio >>> >> >> >
