• Incorporating a new topology in Booksim
  • 1. 新拓扑结构
  • 2. 需要添加的文件
  • 3. 修改步骤
    • 3.1 添加testnet.hpp
    • 3.2 添加testnet.cpp
    • 3.3 将testnet集成到network.cpp中
    • 3.4 创建配置文件testnetconfig
    • 3.5 在main.cpp和global.hpp中加入gP_testnet和gA_testnet变量
    • 3.6 make进行编译
  • 4. 仿真模拟结果

Incorporating a new topology in Booksim

1. 新拓扑结构

如图1所示，拟集成一种上述的拓扑。

2. 需要添加的文件

在Booksim中集成新的拓扑，我们需要添加如下文件：

• 拓扑文件
  • testnet.cpp
  • testnet.cpp
• 配置文件
  • Testnetconfig
• 修改文件
  • network.cpp

3. 修改步骤

3.1 添加testnet.hpp

 #ifndef _TestNet_HPP_#define _TestNet_HPP_#include "network.hpp"#include "routefunc.hpp"class TestNet : public Network {public:TestNet( const Configuration &config, const string & name );static void RegisterRoutingFunctions() ;private:int _a;// 路由器总数int _p;// 每个路由器管理的处理节点int _k;// 每个路由器的端口数void _ComputeSize( const Configuration &config );// 计算拓扑大小void _BuildNet( const Configuration& config );// 构建网络};int testnet_port(int rID, int src, int dest);//// Routing Functions//void min_testnet( const Router *r, const Flit *f, int in_channel, OutputSet *outputs, bool inject ) ;#endif

3.2 添加testnet.cpp

1. 构造函数

TestNet::TestNet( const Configuration& config, const string & name ) 
: Network(config, name) 
{
cout<< "testnet constructor starts..."<<endl;
_ComputeSize(config);
_Alloc();
_BuildNet(config);
cout<< "testnet constructor ends..."<<endl;}

2. _ComputeSize()

void TestNet::_ComputeSize( const Configuration &config ) {cout<< "_ComputeSize starts..."<<endl;// _a _p _k 均为硬编码，但可以使用GetInt()从配置文件中获取
_a = 4;// 路由器总数
_p = 3;// 每个路由器管理的处理节点_k = (_a-1) + _p;// 每个路由器的端口数// 以下三个参数为network中需要使用的
_nodes    = _a * _p; // Number of nodes in network 总节点数(除却路由器)
_size     = _a + _a * _p;      // Number of routers in network 包括路由器和处理节点
_channels = _a * (_a-1);     // 路由器之间的uni-directional link，不包括处理节点// 全局变量，路由函数需要
gP_testnet = _p;
gA_testnet = _a;cout<< "_ComputeSize ends..."<<endl;
}

3. _Alloc()
   _Alloc()定义在network.cpp，用于分配注入弹出通道和路由器link。

4. _BuildNet()
   _BuildNet()初始化路由器，添加所有的通道。如下图所示：
   

void TestNet::_BuildNet( const Configuration& config ) {
// for every router // build the router object// add the links to the processing nodes// add the links to the other routersostringstream router_name;
int node;
int c, cnt;
int port_to_routers = _a - 1;for (node = 0; node < _a; ++node) {// create routerrouter_name<< "router";router_name<< "_"<< node;// k是输入输出端口数_routers[node] = Router::NewRouter(config, this, router_name.str(), node, _k, _k);_timed_modules.push_back(_routers[node]);router_name.str("");// add input and output channels to processing nodesfor(cnt = 0; cnt < _p; cnt++){c = _p * node + cnt; // for router 0, c is 0,1,2; router 1, c is 3,4,5 and so on._routers[node]->AddInputChannel(_inject[c], _inject_cred[c]);}for(cnt = 0; cnt < _p; cnt++){c = _p * node + cnt; // for router 0, c is 0,1,2; router 1, c is 3,4,5 and so on._routers[node]->AddOutputChannel(_eject[c], _eject_cred[c]);}// add output and input channels to other routers// add output channelsfor(cnt = 0; cnt < _a - 1; cnt++){c = port_to_routers * node + cnt; // for router 0, c is 0,1,2; router 1, c is 3,4,5 and so on._routers[node]->AddOutputChannel(_chan[c], _chan_cred[c]);}// add input channelsfor(cnt = 0; cnt < _a; cnt++){if(cnt == node){continue;// do nothing}else if(cnt < node){c = cnt * port_to_routers - 1 + node;}else if(cnt > node){c = cnt * port_to_routers + node;}_routers[node]->AddInputChannel(_chan[c], _chan_cred[c]);}
}
}

5. RegisterRoutingFunctions()
   该函数注册拓扑的路由算法，而gRoutingFunctionMap定义在routefunc.cpp

void TestNet::RegisterRoutingFunctions() {gRoutingFunctionMap["min_testnet"] = &min_testnet;
}

对于一组特定的router, flit和input channel, 需要提供一个output port和output VC用于路由。
6. testnet_port(int rID, int src, int dest)选择正确的输出端口

int testnet_port(int rID, int src, int dest)// find the right port
{int dst_router;int out_port;dst_router = dest / gP_testnet;if(rID == dst_router)// 目标node是在当前路由器管理之下{out_port = dest % gP_testnet;}else// 如果是在其他router下管理{if(dst_router < rID){out_port = gP_testnet + dst_router;}else{out_port = gP_testnet + dst_router - 1;}}return out_port;
}

7. min_testnet()进行路由

void min_testnet( const Router *r, const Flit *f, int in_channel, OutputSet *outputs, bool inject )
{int debug = f->watch;outputs->Clear();if(inject){int inject_vc = RandomInt(gNumVCs-1);outputs->AddRange(-1, inject_vc, inject_vc);return;}int rID = r->GetID();int out_port = -1;int out_vc = 0;if(in_channel < gP_testnet)// source node assign to vc0{out_vc = 0;}else// dest node assign it to vc1{out_vc = 1;}out_port = testnet_port(rID, f->src, f->dest);outputs->AddRange(out_port, out_vc, out_vc);if(debug){*gWatchOut << GetSimTime()<<" | "<<r->FullName()<<" | "<<" through output port : "<< out_port<<" out vc: "<< out_vc << endl;}
}

3.3 将testnet集成到network.cpp中

- 添加testnet.hpp

- 加入testnet拓扑

3.4 创建配置文件testnetconfig

```
// Topology
topology = testnet;//a = 4;
//p = 3;//Routing
routing_function = min;// Flow control
num_vcs = 2;// Traffic
traffic = uniform;
injection_rate = 0.25;
```

3.5 在main.cpp和global.hpp中加入gP_testnet和gA_testnet变量

3.6 make进行编译

4. 仿真模拟结果

• a = 4, p = 3时运行booksim得到如下结果：

====== Overall Traffic Statistics ======
====== Traffic class 0 ======
Packet latency average = 14.392 (1 samples)minimum = 7 (1 samples)maximum = 78 (1 samples)
Network latency average = 14.3911 (1 samples)minimum = 7 (1 samples)maximum = 78 (1 samples)
Flit latency average = 14.4049 (1 samples)minimum = 7 (1 samples)maximum = 78 (1 samples)
Fragmentation average = 0 (1 samples)minimum = 0 (1 samples)maximum = 0 (1 samples)
Injected packet rate average = 0.250979 (1 samples)minimum = 0.24025 (1 samples)maximum = 0.26 (1 samples)
Accepted packet rate average = 0.251208 (1 samples)minimum = 0.23125 (1 samples)maximum = 0.27025 (1 samples)
Injected flit rate average = 0.250979 (1 samples)minimum = 0.24025 (1 samples)maximum = 0.26 (1 samples)
Accepted flit rate average = 0.251208 (1 samples)minimum = 0.23125 (1 samples)maximum = 0.27025 (1 samples)
Injected packet size average = 1 (1 samples)
Accepted packet size average = 1 (1 samples)
Hops average = 1.74948 (1 samples)
Total run time 0.0592558

• a = 8, p = 4时运行booksim得到如下结果：

====== Overall Traffic Statistics ======
====== Traffic class 0 ======
Packet latency average = 14.1645 (1 samples)minimum = 7 (1 samples)maximum = 40 (1 samples)
Network latency average = 14.1645 (1 samples)minimum = 7 (1 samples)maximum = 40 (1 samples)
Flit latency average = 14.1681 (1 samples)minimum = 7 (1 samples)maximum = 40 (1 samples)
Fragmentation average = 0 (1 samples)minimum = 0 (1 samples)maximum = 0 (1 samples)
Injected packet rate average = 0.248344 (1 samples)minimum = 0.236 (1 samples)maximum = 0.261667 (1 samples)
Accepted packet rate average = 0.248417 (1 samples)minimum = 0.223667 (1 samples)maximum = 0.273667 (1 samples)
Injected flit rate average = 0.248344 (1 samples)minimum = 0.236 (1 samples)maximum = 0.261667 (1 samples)
Accepted flit rate average = 0.248417 (1 samples)minimum = 0.223667 (1 samples)maximum = 0.273667 (1 samples)
Injected packet size average = 1 (1 samples)
Accepted packet size average = 1 (1 samples)
Hops average = 1.87333 (1 samples)
Total run time 0.14817