I was recently ugrading to es 2.1.0 cluster and java client API.
I have a usecase were I constantly add new fields via the update api to some existing index which contains aprox 3000 fields. After upgrading to 2.1.0 ( server + client ) I started noticing ProcessClusterEventTimeoutException[failed to process cluster event (put-mapping .... (it takes more than 30 seconds). Also in the es logs I see a lot of entries containing update_mapping.
However, this slow processing of update_mapping was not reported with es 1.x. Does anybody know why is this slower with 2.1.0?