packetbeat af_packet丢包

最近在使用packetbeat来捕获流量中的http包。packetbeat部署在物理机上，捕获的是镜像流量，启用af_packet模式，镜像流量中只有tcp流量，没有udp。
 
packetbeat版本为：6.2.4
操作系统为：ubuntu16.04
 
我的packetbeat配置如下：
#============================== Network device ================================
packetbeat.interfaces.device: eth0
packetbeat.interfaces.type: af_packet
packetbeat.interfaces.buffer_size_mb: 3072
#========================== Transaction protocols =============================
packetbeat.protocols:
- type: http
  ports: [80, 7001, 8080, 8000, 8001, 8081, 5000, 5001, 8002, 11080, 82, 7002, 8088, 18880]
  send_all_headers: true
  include_body_for: ["text/xml", "text/html", "text/plain", "application/xml", "application/json", "multipart/form-data", "application/csv", "text/csv", "application/x-ndjson", "application/x-amf"]
  split_cookie: true
  #transaction_timeout: 20s
#================================ General =====================================
processors:
- drop_event:
    when:
       not:
           or:
                - regexp:
                      ip: "10.xxx.*.*"
                - regexp:
                      ip: "10.xxx.*.*"
#------------------------------- Kafka output ----------------------------------
output.kafka:
  enabled: true
  hosts: ["10.xx.xx.xx:9092"]
  topic: xxx
  worker: 6#---------------------------------------------------------------------------------
 
 
发现当网络流量为400+m/s的时候，packetbeat有时会产生较严重的丢包，大约会丢10+%，有时甚至可以丢包80%。请问这是正常情况吗？如何可以调优呢，物理机资源足够。
注意：
1、通过排查packetbeat的日志，未发现其他问题
2、已经关闭了gro功能