By default searches run without a field specified. ES's behavior is to then run the search against a field "_any" which internally rolls up all the other fields. However maintaining this _any field eats a not insignificant portion of disk. To resolve this dependency on the existence of "_any" for unspecified field searches the default behavior should be that searches run against @message if no field is explicitly specified.
No work will be done on the current logstash-web and will be replaced by Kibana ( www.kibana.org )
Currently there are 2 options.
1) Wait until Kibana is runnable from logstash.
2) Run kibana your self.