index created for multiple table from a database. Over a period of time record of a couple of table increased and a couple of table has millions of record. but initially it has hundreds of record. So if count of records are increased, how do make better performance.
1) do we need to move the table from old index to newly creating index
or
2) increase the nodes and shards of existing index, thus make better performance.

so i am looking better solution and pls let me know, if my requirement is not clear.

Could anybody answer please.