Hi, As Helix is going to support bigger clusters with more nodes, more resources, and more partitions, using ZK as metadata store seems not scalable. This is especially the case for ideal states and external views where Helix stores all partition states and mappings. Alternatively, we can use for example, a key-value store for ideal states and external views, while leaving minimum information on ZK, say URL to the metadata store. Helix listeners will still get ZK callbacks on all state changes, then reads the URL, and retrieve the actual data from the more scalable metadata stores. Any thoughts?
Thanks, Jason
