NetHogs是一个Linux命令行工具，实现按进程实时统计网络带宽
介绍
NetHogs 是一款小型的 net top 工具。它不像大多数工具那样按协议或子网细分流量，而是按进程分组带宽。
安装
Ubuntu
apt install nethogs
Redhat
yum install nethogs
使用
Help
$ nethogs -h
usage: nethogs [-V] [-h] [-b] [-d seconds] [-v mode] [-c count] [-t] [-p] [-s] [device [device [device ...]]]
-V : prints version.
-h : prints this help.
-b : bughunt mode - implies tracemode.
-d : delay for update refresh rate in seconds. default is 1.
-v : view mode (0 = KB/s, 1 = total KB, 2 = total B, 3 = total MB). default is 0.
-c : number of updates. default is 0 (unlimited).
-t : tracemode.
-p : sniff in promiscious mode (not recommended).
-s : sort output by sent column.
-a : monitor all devices, even loopback/stopped ones.
device : device(s) to monitor. default is all interfaces up and running excluding loopback
When nethogs is running, press:
q: quit
s: sort by SENT traffic
r: sort by RECEIVE traffic
m: switch between total (KB, B, MB) and KB/s mode
运行时，快捷键调整显示情况：
s：按 SENT 流量排序r：按 RECEIVE 流量排序m：在总（KB，B，MB）和 KB/s 模式之间切换q：退出命令提示符
示例
$ nethogs
# 监听指定网卡
$ nethogs eth0
# 每5秒刷新一次
$ nethogs -d 5