Hi, Has Solr tried to use vnodes concept like Cassandra: https://www.datastax.com/dev/blog/virtual-nodes-in-cassandra-1-2
If this can be implemented carefully, we need not live with just shard-splitting alone that can only double the number of shards. With vnodes, shards can be increased incrementally as the need arises. What's more, shards can be decreased too when the doc-count/traffic decreases. -SG
