为什么不对Elasticsearch使用最大复制？

Question

Can someone explain to me why, if disk space is not an issue, I don't want maximum replication such that every node has every shard?

It seems to me that there would be no real downside here as long as I'm not worried about filling up a disk and my updates happen infrequently and in a timely manner.

Am I missing the obvious? ;)

Answer 1

The only downsides I can see are:

1. When you get a new document you'll need to write to all nodes - but you say updates are infrequent so this shouldn't be an issue
2. If you add a node or need to restore a node it will receive a lot of data (copies of all shards) - however you can throttle this in the node config file.

So - generally it's a good idea to have replication to all nodes.