Need forward the logs faster in some scenario. Thanks

I am forwarding logs to cloudwtach, with fluent-plugin-cloudwatch-logs.
I want to forward the logs as fast as possible, for an important demo.
But still need 2 minutes to forward the logs. Is there anyway to improve ? Thanks a lot.
Here is my conf:

<source>
      @type tail
      enable_stat_watcher false
      refresh_interval 1 
      read_from_head true
      rotate_wait 3
      enable_watch_timer true
      open_on_every_update false
      path /var/log/containers/*.log
      pos_file /var/log/fluentd-containers.log.pos
      time_format %Y-%m-%dT%H:%M:%S.%NZ
      tag kubernetes.*
      format json
      read_from_head true
    </source>
 ......
    <match **_istio-proxy-**>
      @type cloudwatch_logs
      log_group_name "#{ENV['LOG_GROUP_NAME']}"
      auto_create_stream true
      use_tag_as_stream true
      fetch_interval 1
      max_events_per_batch 1000
      <buffer>
        flush_at_shutdown true
        flush_mode immediate
        flush_thread_count 8
        flush_thread_interval 1
        flush_thread_burst_interval 1
        retry_forever true
        retry_type exponential_backoff
      </buffer>
    </match>

Hey John, with some backends the normal ingestion speed is a few seconds to a few minutes. Are you sure that this is not something on the CloudWatch side? It might be worth checking with AWS