不多说，直接上干货！
suricata的基本组成。Suricata是由所谓的线程（threads）、线程模块 （thread-modules）和队列（queues）组成。Suricata是一个多线程的程序，因此在同一时刻会有多个线程在工作。线程模块是依据 功能来划分的，比如一个模块用于解析数据包，另一个模块用于检测数据包等。每个数据包可能会有多个不同的线程进行处理，队列就是用于将数据包从一个线程传 递到另一个线程。与此同时，一个线程可以拥有多个线程模块，但是在某一时刻只有一个模块在运行（原文是If they have more modules, they can only be active on a a time.看不大懂，感觉是这个意思）。
Suricata支持多种运行模式。运行模式决定了不同的线程如何用于IDS。
以下命令可以查看所有 可用的运行模式。
[root@suricata ~]# sudo /usr/local/bin/suricata --list-runmodes
------------------------------------- Runmodes ------------------------------------------
| RunMode Type | Custom Mode | Description
|----------------------------------------------------------------------------------------
| PCAP_DEV | single | Single threaded pcap live mode
| ---------------------------------------------------------------------
| | autofp | Multi threaded pcap live mode. Packets from each flow are assigned to a single detect thread, unlike "pcap_live_auto" where packets from the same flow can be processed by any detect thread
| ---------------------------------------------------------------------
| | workers | Workers pcap live mode, each thread does all tasks from acquisition to logging
|----------------------------------------------------------------------------------------
| PCAP_FILE | single | Single threaded pcap file mode
| ---------------------------------------------------------------------
| | autofp | Multi threaded pcap file mode. Packets from each flow are assigned to a single detect thread, unlike "pcap-file-auto" where packets from the same flow can be processed by any detect thread
|----------------------------------------------------------------------------------------
| PFRING(DISABLED) | autofp | Multi threaded pfring mode. Packets from each flow are assigned to a single detect thread, unlike "pfring_auto" where packets from the same flow can be processed by any detect thread
| ---------------------------------------------------------------------
| | single | Single threaded pfring mode
| ---------------------------------------------------------------------
| | workers | Workers pfring mode, each thread does all tasks from acquisition to logging
|----------------------------------------------------------------------------------------
| NFQ | autofp | Multi threaded NFQ IPS mode with respect to flow
| ---------------------------------------------------------------------
| | workers | Multi queue NFQ IPS mode with one thread per queue
|----------------------------------------------------------------------------------------
| NFLOG | autofp | Multi threaded nflog mode
| ---------------------------------------------------------------------
| | single | Single threaded nflog mode
| ---------------------------------------------------------------------
| | workers | Workers nflog mode
|----------------------------------------------------------------------------------------
| IPFW | autofp | Multi threaded IPFW IPS mode with respect to flow
| ---------------------------------------------------------------------
| | workers | Multi queue IPFW IPS mode with one thread per queue
|----------------------------------------------------------------------------------------
| ERF_FILE | single | Single threaded ERF file mode
| ---------------------------------------------------------------------
| | autofp | Multi threaded ERF file mode. Packets from each flow are assigned to a single detect thread
|----------------------------------------------------------------------------------------
| ERF_DAG | autofp | Multi threaded DAG mode. Packets from each flow are assigned to a single detect thread, unlike "dag_auto" where packets from the same flow can be processed by any detect thread
| ---------------------------------------------------------------------
| | single | Singled threaded DAG mode
| ---------------------------------------------------------------------
| | workers | Workers DAG mode, each thread does all tasks from acquisition to logging
|----------------------------------------------------------------------------------------
| AF_PACKET_DEV | single | Single threaded af-packet mode
| ---------------------------------------------------------------------
| | workers | Workers af-packet mode, each thread does all tasks from acquisition to logging
| ---------------------------------------------------------------------
| | autofp | Multi socket AF_PACKET mode. Packets from each flow are assigned to a single detect thread.
|----------------------------------------------------------------------------------------
| NETMAP(DISABLED) | single | Single threaded netmap mode
| ---------------------------------------------------------------------
| | workers | Workers netmap mode, each thread does all tasks from acquisition to logging
| ---------------------------------------------------------------------
| | autofp | Multi threaded netmap mode. Packets from each flow are assigned to a single detect thread.
|----------------------------------------------------------------------------------------
| UNIX_SOCKET | single | Unix socket mode
|----------------------------------------------------------------------------------------
[root@suricata ~]#
Suricata的运行方式就是上面介绍的线程（threads）、线程模块（thread-modules）和队列（queues）三种元素的不 同组合方式。
上图中的RunMode Type并不是配置文件中的runmodes选项，而是后面的Custom Mode也就是自定义模式才可以在此处设置。比如默认的Runmodes是autofp，在线实时检测流量的模式中其结构如下，单线程模块获取数据包和解码，多线程模块检测。
以下大家也可以去官网看。
https://redmine.openinfosecfoundation.org/projects/suricata/wiki/Runmodes
Example of the default runmode:（即这是Suricata的的默认运行模式：autofp）
Suricata使用的默认运行模式是autofp(代表“自动流绑定负载均衡模式”)。在这种模式下，来自每一路流的数据包被分配给单一的检测线程。流被分配给了未处理数据包数量最少的线程。
In the pfring mode, every flow follows its own fixed route in the runmode.
