One of our application uses Elasticsearch (1.4.4) as an in-memory cache. The application is a Java webapp deployed on Tomcat 7 with Oracle 1.7. The elasticsearch instance is a one-node setup deployed on the same server.
Since elasticsearch 1.3.3 we're expiriencing around 40 MBit/s in and out on the loopback interface between the application and the Elasticsearch node with an idle application.
This isn't that much but causes a noticable load for an otherwise flatlining system. I don't have a production system with this application at hand so i can't really say how it evolves in prod.
Grabbing the traffic via tcpdump and analyzing it in Wireshark shows that the Elasticsearch-Client in the application continously ask the Node for cluster/node/info
which yields in a 10k answer every time.
Maybe totally unrelated, but enabling the server and client logging gives us:
Elasticsearch Server log:
[2015-05-12 14:45:01,600][INFO ][node ] [Illyana Rasputin] initializing ...
[2015-05-12 14:45:01,608][INFO ][plugins ] [Illyana Rasputin] loaded [], sites []
[2015-05-12 14:45:06,666][INFO ][node ] [Illyana Rasputin] initialized
[2015-05-12 14:45:06,667][INFO ][node ] [Illyana Rasputin] starting ...
[2015-05-12 14:45:06,828][INFO ][transport ] [Illyana Rasputin] bound_address {inet[/0:0:0:0:0:0:0:0:9300]}, publish_address {inet[/10.24.1.128:9300]}
[2015-05-12 14:45:06,851][INFO ][discovery ] [Illyana Rasputin] bkbo_index/TITPDFdtR6SXX5EeOXaidg
[2015-05-12 14:45:09,892][INFO ][cluster.service ] [Illyana Rasputin] new_master [Illyana Rasputin][TITPDFdtR6SXX5EeOXaidg][dev06][inet[/10.24.1.128:9300]], reason: zen-disco-join (elected_as_master)
[2015-05-12 14:45:09,943][INFO ][http ] [Illyana Rasputin] bound_address {inet[/0:0:0:0:0:0:0:0:9200]}, publish_address {inet[/10.24.1.128:9200]}
[2015-05-12 14:45:09,944][INFO ][node ] [Illyana Rasputin] started
[2015-05-12 14:45:11,283][INFO ][gateway ] [Illyana Rasputin] recovered [2] indices into cluster_state
Elasticsearch client:
2015-05-12 14:46:40,683 INFO [localhost-startStop-1] PluginsService:<init>:151 [Antiphon the Overseer] loaded [], sites []
2015-05-12 14:46:41,548 DEBUG [localhost-startStop-1] TransportClientNodesService:<init>:110 [Antiphon the Overseer] node_sampler_interval[5ms]
2015-05-12 14:46:41,594 DEBUG [localhost-startStop-1] TransportClientNodesService:addTransportAddresses:167 [Antiphon the Overseer] adding address [[#transport#-1][dev06][inet[localhost/127.0.0.1:9300]]]
2015-05-12 14:46:41,625 DEBUG [localhost-startStop-1] NettyTransport:connectToNode:751 [Antiphon the Overseer] connected to node [[#transport#-1][dev06][inet[localhost/127.0.0.1:9300]]]
2015-05-12 14:46:41,655 INFO [localhost-startStop-1] TransportClientNodesService$SimpleNodeSampler:doSample:371 [Antiphon the Overseer] failed to get node info for [#transport#-1][dev06][inet[localhost/127.0.0.1:9300]], disconnecting...
org.elasticsearch.transport.ReceiveTimeoutTransportException: [][inet[localhost/127.0.0.1:9300]][cluster:monitor/nodes/info] request_id [0] timed out after [6ms]
at org.elasticsearch.transport.TransportService$TimeoutHandler.run(TransportService.java:366)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
2015-05-12 14:46:41,658 DEBUG [localhost-startStop-1] NettyTransport:disconnectFromNode:882 [Antiphon the Overseer] disconnecting from [[#transport#-1][dev06][inet[localhost/127.0.0.1:9300]]] due to explicit disconnect call
2015-05-12 14:46:41,661 DEBUG [elasticsearch[Antiphon the Overseer][generic][T#1]] NettyTransport:connectToNode:751 [Antiphon the Overseer] connected to node [[#transport#-1][dev06][inet[localhost/127.0.0.1:9300]]]
2015-05-12 14:46:41,669 INFO [elasticsearch[Antiphon the Overseer][generic][T#1]] TransportClientNodesService$SimpleNodeSampler:doSample:371 [Antiphon the Overseer] failed to get node info for [#transport#-1][dev06][inet[localhost/127.0.0.1:9300]], disconnecting...
org.elasticsearch.transport.ReceiveTimeoutTransportException: [][inet[localhost/127.0.0.1:9300]][cluster:monitor/nodes/info] request_id [1] timed out after [5ms]
at org.elasticsearch.transport.TransportService$TimeoutHandler.run(TransportService.java:366)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
2015-05-12 14:46:41,670 DEBUG [elasticsearch[Antiphon the Overseer][generic][T#1]] NettyTransport:disconnectFromNode:882 [Antiphon the Overseer] disconnecting from [[#transport#-1][dev06][inet[localhost/127.0.0.1:9300]]] due to explicit disconnect call
2015-05-12 14:46:41,676 DEBUG [elasticsearch[Antiphon the Overseer][generic][T#1]] NettyTransport:connectToNode:751 [Antiphon the Overseer] connected to node [[#transport#-1][dev06][inet[localhost/127.0.0.1:9300]]]
2015-05-12 14:46:41,677 WARN [elasticsearch[Antiphon the Overseer][transport_client_worker][T#2]{New I/O worker #2}] TransportService$Adapter:remove:280 [Antiphon the Overseer] Received response for a request that has timed out, sent [14ms] ago, timed out [9ms] ago, action [cluster:monitor/nodes/info], node [[#transport#-1][dev06][inet[localhost/127.0.0.1:9300]]], id [1]
2015-05-12 14:46:41,682 INFO [localhost-startStop-1] PluginsService:<init>:151 [Ricochet] loaded [], sites []
2015-05-12 14:46:41,722 DEBUG [localhost-startStop-1] TransportClientNodesService:<init>:110 [Ricochet] node_sampler_interval[5ms]
2015-05-12 14:46:41,733 DEBUG [localhost-startStop-1] TransportClientNodesService:addTransportAddresses:167 [Ricochet] adding address [[#transport#-1][dev06][inet[localhost/127.0.0.1:9300]]]
2015-05-12 14:46:41,734 DEBUG [localhost-startStop-1] NettyTransport:connectToNode:751 [Ricochet] connected to node [[#transport#-1][dev06][inet[localhost/127.0.0.1:9300]]]
2015-05-12 14:46:41,759 DEBUG [elasticsearch[Antiphon the Overseer][generic][T#1]] NettyTransport:connectToNode:751 [Antiphon the Overseer] connected to node [[Illyana Rasputin][TITPDFdtR6SXX5EeOXaidg][dev06][inet[localhost/127.0.0.1:9300]]]
2015-05-12 14:46:41,760 DEBUG [localhost-startStop-1] NettyTransport:connectToNode:751 [Ricochet] connected to node [[Illyana Rasputin][TITPDFdtR6SXX5EeOXaidg][dev06][inet[localhost/127.0.0.1:9300]]]
Yes, this application has two client connections which should be OK (according to the devs). These disconnect/reconnect cycles happen about every minute or so.
Any clues whats going on here? I already disabled multicasting via discovery.zen.ping.multicast.enabled: false
.