yep, I even deleted and recreated the index too 
I've already checked your reply in https://discuss.elastic.co/t/kibana-shows-fields-are-not-searchable-and-aggregatable/89148/6 and that's how I queried for the _field_caps.
I'm using the csv filter in logstash and the mutate filter to convert it to float.
"VMs_per_core" => "float"
"vCPUs_per_core" => "float"
"Num_VCPUs" => "integer"