Logstash TCP input pipeline performance issues

The problem is in the http output of the "env_tcp" pipeline. If you go through your stats and look at the "events" entries the only one that has an imbalance is

  "events": {
    "in": 1983728,
    "filtered": 1891560,
    "out": 1891560,
....
  "pipelines": {
....
"env_tcp": {
  "events": {
    "queue_push_duration_in_millis": 40873948,
    "duration_in_millis": 151879287,
    "filtered": 1713729,
    "out": 1713729,
    "in": 1805897
  },

There are 30,000+ events going in and not coming out. Check Guy's post here. This is not a slow input.

    "outputs": [ ....
      {
        "id": "c685636696572b6d74ea68ff726974823e22f806987cff4044310f1b953496a5",
        "name": "http",
        "events": {
          "duration_in_millis": 151778979,
          "out": 1713729,
          "in": 1759809
        }
      }
    ]
  },

Again, there are tens of thousands of event reaching the http output and not leaving. It is taking nearly a tenth of a second per event. It could be that encoding the events is really expensive, but I would concur with Leandro that the first place to look is the http destination.