Showing cluster state convergence #124
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This allows to show convergence: - when no convergence is reached yet, the heartbeat blinks in red - when a gossip was received in which all members have seen the latest state, the heartbeat blinks 3 times in green - it then reverts to blinking in white Some notes: - classes moved to package `akka.cluster.pi` or else we can't follow the (internal) event - gossip is slowed down so that it is possible to see things happen - this is only applied to exercise 2 so far, since it might be distracting if it is shown all the time (and because I didn't want to introduce a PR with changes to package structure in all exercises) I'll post a video about how this looks like online shortly.
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@manuelbernhardt
This looks pretty cool! Will give this a try to see it in action. I noticed that you renamed the package from org.neopixel to akka.cluster.pi which is something that should have been done a long time ago. This is a historic artefact from the very start of the project when I was taking the first steps to control the Adafruit Neopixel LED strips.
| @@ -36,6 +36,13 @@ akka { | |||
| "akka://pi-"${cluster-node-configuration.cluster-id}"-system@"${cluster-node-configuration.seed-node-2}":2550", | |||
| "akka://pi-"${cluster-node-configuration.cluster-id}"-system@"${cluster-node-configuration.seed-node-3}":2550", | |||
| "akka://pi-"${cluster-node-configuration.cluster-id}"-system@"${cluster-node-configuration.seed-node-4}":2550"] | |||
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| gossip-interval = 2s | |||
| gossip-time-to-live = 4s | |||
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@manuelbernhardt
Note: It's probably a good idea to add a comment stating that this parameter tweaking is done to slow down the convergence process for demo purposes and that this shouldn't be done unless one knows very well why. WDYT?
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@manuelbernhardt
Tried it out and it works really nice!
- I would add some general explanation about the idea of slowing down the gossip communication in the exercise README. By the way, I ran the same code using the default params, and then the LED stay in the red blinking state. That shouldn't happen, isn't it?
- Good point to change the package for the
ClusterStatusTracker: this should be applied to all exercises. I will create an issue for that to follow-up separately.
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@eloots thanks! If you set |
Thanks! That clarifies matters. I'll go ahead and merge. Also, as you mentioned, maybe keep this feature limited to this exercise? |
This allows to show convergence:
Some notes:
akka.cluster.pior else we can't follow the (internal) eventI'll post a video about how this looks like online shortly.