We're working with an index table whose row is a shardId (an integer, like the wiki-search or IndexedDoc examples). I was just wondering what the right strategy is for choosing a number of partitions, particularly given a cluster that could potentially grow.
If I simply set the number of shards equal to the number of slave nodes, additional nodes would not improve query performance (at least over the data already ingested). But starting with more partitions than slave nodes would result in multiple tablets per tablet server… I'm not really sure how that would impact performance, particularly given that all queries against the table will be batchscanners with an infinite range.
Just wondering how others have addressed this problem, and if there are any performance rules of thumb regarding the ratio of tablets to tablet servers.