I have setup Logstash to take input from one ES index based on a query and then output to another ES index. It is working, but going very slowly, and from the logs it seems to be stopping and starting every few seconds. Is this normal behaviour or is something going wrong that I should look into?
Here is an example of the logs I'm seeing:
[2019-03-22T10:27:58,168][INFO ][logstash.pipeline ] Pipeline started successfully {:pipeline_id=>"main", :thread=>"#<Thread:0x5e40ab63 run>"}
[2019-03-22T10:27:58,220][INFO ][logstash.agent ] Pipelines running {:count=>1, :running_pipelines=>[:main], :non_running_pipelines=>[]}
[2019-03-22T10:27:58,458][INFO ][logstash.agent ] Successfully started Logstash API endpoint {:port=>9600}
[2019-03-22T10:28:02,760][INFO ][logstash.pipeline ] Pipeline has terminated {:pipeline_id=>"main", :thread=>"#<Thread:0x5e40ab63 run>"}
[2019-03-22T10:28:18,657][INFO ][logstash.runner ] Starting Logstash {"logstash.version"=>"6.6.2"}
[2019-03-22T10:28:23,536][INFO ][logstash.pipeline ] Starting pipeline {:pipeline_id=>"main", "pipeline.workers"=>12, "pipeline.batch.size"=>125, "pipeline.batch.delay"=>50}
[2019-03-22T10:28:23,922][INFO ][logstash.outputs.elasticsearch] Elasticsearch pool URLs updated {:changes=>{:removed=>[], :added=>[http://localhost:9201/]}}
[2019-03-22T10:28:24,094][WARN ][logstash.outputs.elasticsearch] Restored connection to ES instance {:url=>"http://localhost:9201/"}
[2019-03-22T10:28:24,165][INFO ][logstash.outputs.elasticsearch] ES Output version determined {:es_version=>6}
[2019-03-22T10:28:24,168][WARN ][logstash.outputs.elasticsearch] Detected a 6.x and above cluster: the `type` event field won't be used to determine the document _type {:es_version=>6}
[2019-03-22T10:28:24,207][INFO ][logstash.outputs.elasticsearch] New Elasticsearch output {:class=>"LogStash::Outputs::ElasticSearch", :hosts=>["//localhost:9201"]}
[2019-03-22T10:28:24,237][INFO ][logstash.outputs.elasticsearch] Using mapping template from {:path=>nil}
[2019-03-22T10:28:24,268][INFO ][logstash.outputs.elasticsearch] Attempting to install template {:manage_template=>{"template"=>"logstash-*", "version"=>60001, "settings"=>{"index.refresh_interval"=>"5s"}, "mappings"=>{"_default_"=>{"dynamic_templates"=>[{"message_field"=>{"path_match"=>"message", "match_mapping_type"=>"string", "mapping"=>{"type"=>"text", "norms"=>false}}}, {"string_fields"=>{"match"=>"*", "match_mapping_type"=>"string", "mapping"=>{"type"=>"text", "norms"=>false, "fields"=>{"keyword"=>{"type"=>"keyword", "ignore_above"=>256}}}}}], "properties"=>{"@timestamp"=>{"type"=>"date"}, "@version"=>{"type"=>"keyword"}, "geoip"=>{"dynamic"=>true, "properties"=>{"ip"=>{"type"=>"ip"}, "location"=>{"type"=>"geo_point"}, "latitude"=>{"type"=>"half_float"}, "longitude"=>{"type"=>"half_float"}}}}}}}}
[2019-03-22T10:28:24,601][INFO ][logstash.pipeline ] Pipeline started successfully {:pipeline_id=>"main", :thread=>"#<Thread:0x54e60578 sleep>"}
[2019-03-22T10:28:24,658][INFO ][logstash.agent ] Pipelines running {:count=>1, :running_pipelines=>[:main], :non_running_pipelines=>[]}
[2019-03-22T10:28:24,912][INFO ][logstash.agent ] Successfully started Logstash API endpoint {:port=>9600}
[2019-03-22T10:28:29,221][INFO ][logstash.pipeline ] Pipeline has terminated {:pipeline_id=>"main", :thread=>"#<Thread:0x54e60578 run>"}
[2019-03-22T10:28:45,143][INFO ][logstash.runner ] Starting Logstash {"logstash.version"=>"6.6.2"}
[2019-03-22T10:28:49,927][INFO ][logstash.pipeline ] Starting pipeline {:pipeline_id=>"main", "pipeline.workers"=>12, "pipeline.batch.size"=>125, "pipeline.batch.delay"=>50}
[2019-03-22T10:28:50,319][INFO ][logstash.outputs.elasticsearch] Elasticsearch pool URLs updated {:changes=>{:removed=>[], :added=>[http://localhost:9201/]}}
[2019-03-22T10:28:50,509][WARN ][logstash.outputs.elasticsearch] Restored connection to ES instance {:url=>"http://localhost:9201/"}
[2019-03-22T10:28:50,569][INFO ][logstash.outputs.elasticsearch] ES Output version determined {:es_version=>6}
[2019-03-22T10:28:50,573][WARN ][logstash.outputs.elasticsearch] Detected a 6.x and above cluster: the `type` event field won't be used to determine the document _type {:es_version=>6}
[2019-03-22T10:28:50,613][INFO ][logstash.outputs.elasticsearch] New Elasticsearch output {:class=>"LogStash::Outputs::ElasticSearch", :hosts=>["//localhost:9201"]}
[2019-03-22T10:28:50,632][INFO ][logstash.outputs.elasticsearch] Using mapping template from {:path=>nil}
[2019-03-22T10:28:50,672][INFO ][logstash.outputs.elasticsearch] Attempting to install template {:manage_template=>{"template"=>"logstash-*", "version"=>60001, "settings"=>{"index.refresh_interval"=>"5s"}, "mappings"=>{"_default_"=>{"dynamic_templates"=>[{"message_field"=>{"path_match"=>"message", "match_mapping_type"=>"string", "mapping"=>{"type"=>"text", "norms"=>false}}}, {"string_fields"=>{"match"=>"*", "match_mapping_type"=>"string", "mapping"=>{"type"=>"text", "norms"=>false, "fields"=>{"keyword"=>{"type"=>"keyword", "ignore_above"=>256}}}}}], "properties"=>{"@timestamp"=>{"type"=>"date"}, "@version"=>{"type"=>"keyword"}, "geoip"=>{"dynamic"=>true, "properties"=>{"ip"=>{"type"=>"ip"}, "location"=>{"type"=>"geo_point"}, "latitude"=>{"type"=>"half_float"}, "longitude"=>{"type"=>"half_float"}}}}}}}}
[2019-03-22T10:28:51,009][INFO ][logstash.pipeline ] Pipeline started successfully {:pipeline_id=>"main", :thread=>"#<Thread:0x193b2ab8 run>"}
[2019-03-22T10:28:51,056][INFO ][logstash.agent ] Pipelines running {:count=>1, :running_pipelines=>[:main], :non_running_pipelines=>[]}
[2019-03-22T10:28:51,309][INFO ][logstash.agent ] Successfully started Logstash API endpoint {:port=>9600}
[2019-03-22T10:28:55,612][INFO ][logstash.pipeline ] Pipeline has terminated {:pipeline_id=>"main", :thread=>"#<Thread:0x193b2ab8 run>"}