Adding multiple new nodes into an existing cluster, tablets and consistent topology

[Guy]

Originally from the User Slack

@Johannes_Gilger: Can we add multiple new nodes into an existing scylla cluster at once or do we have to do it one-by-one?

@avi: When consistent topology is enabled, you can add nodes simultaneously. It’s only an improvement when your tables use tablets, however.

@Johannes_Gilger: @avi Thanks, that makes sense. We’ll go one-by-one for now. Still having some issues with the fs.aio-max-nr setting anyway that we need to iron out

@avi: Just increase it 10x