> For the complete documentation index, see [llms.txt](https://hezhiqiang.gitbook.io/elkstack/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hezhiqiang.gitbook.io/elkstack/logstash/cha-jian-pei-zhi/filter/elapsed.md).

# elapsed

```
filter {
  grok {
    match => ["message", "%{TIMESTAMP_ISO8601} START id: (?<task_id>.*)"]
    add_tag => [ "taskStarted" ]
  }
  grok {
    match => ["message", "%{TIMESTAMP_ISO8601} END id: (?<task_id>.*)"]
    add_tag => [ "taskTerminated"]
  }
  elapsed {
    start_tag => "taskStarted"
    end_tag => "taskTerminated"
    unique_id_field => "task_id"
  }
}
```