Sling Topology heartbeat: reduce the amount of repo write activity

2014-02-07 Thread Jörg Hoh
Hi, I am thinking if we reduce the amount of data persisted in the repository with every topology heartbeat. For example we could just update the timestamp of the of announcement hearbeat, if the topology hasn't changed at all (instead of writing the complete announcement). A more radical

Re: Sling Topology heartbeat: reduce the amount of repo write activity

2014-02-07 Thread Stefan Egli
What could be done for level 3: a) at startup the behavior is as is today, cluster-ready, writing repository-heartbeats as configured b) this is done for a configured amount of time at least, eg for 5 minutes (exploring phase) - the idea of this being to avoid any race-conditions of two nodes

Re: Sling Topology heartbeat: reduce the amount of repo write activity

2014-02-07 Thread Jörg Hoh
Hi, some ideas regarding the cluster detection: * When a cluster node comes up, it writes it's intial I am here annoucement to the repo. * The node then comes to the listing mode, in which he listens if there's any pong or if a new ping comes in, but here it doesn't write any cluster heartbeat

Re: Sling Topology heartbeat: reduce the amount of repo write activity

2014-02-07 Thread Stefan Egli
I think this is basically what I proposed - except that I would be careful to handle race-conditions with startups/cluster-delays/observation-threading and thus propose to have a period of a few minutes in which it assumes to be in a cluster, and only afterwards switch back if that's not the case.

Re: Sling Topology heartbeat: reduce the amount of repo write activity

2014-02-07 Thread Carsten Ziegeler
If 1) and 2) are easily doable, I would start with them and see where it leads us Regards Carsten 2014-02-07 16:04 GMT+01:00 Stefan Egli e...@adobe.com: I think this is basically what I proposed - except that I would be careful to handle race-conditions with