1 /* Copyright (c) 2014-2015. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
7 #ifndef SURF_ROUTING_CLUSTER_FAT_TREE_HPP_
8 #define SURF_ROUTING_CLUSTER_FAT_TREE_HPP_
16 #include "surf_routing_cluster.hpp"
21 /** \file surf_routing_cluster_fat_tree.cpp
22 * The class AsClusterFatTree describes PGFT, as introduced by Eitan Zahavi
23 * in "D-Mod-K Routing Providing Non-Blocking Traffic for Shift Permutations
24 * on Real Life Fat Trees" (2010). RLFT are PGFT with some restrictions to
25 * address real world constraints, which are not currently enforced.
28 class XBT_PRIVATE FatTreeNode;
29 class XBT_PRIVATE FatTreeLink;
31 /** \brief A node in a fat tree.
32 * A FatTreeNode can either be a switch or a processing node. Switches are
33 * identified by a negative ID. This class is closely related to fat
37 /** Unique ID which identifies every node. */
39 /* Level into the tree, with 0 being the leafs.
42 /* \brief Position into the level, starting from 0.
44 unsigned int position;
45 /** In order to link nodes between them, each one must be assigned a label,
46 * consisting of l integers, l being the levels number of the tree. Each label
47 * is unique in the level, and the way it is generated allows the construction
48 * of a fat tree which fits the desired topology.
50 std::vector<unsigned int> label;
52 /** Links to the lower level, where the position in the vector corresponds to
55 std::vector<FatTreeLink*> children;
56 /** Links to the upper level, where the position in the vector corresponds to
59 std::vector<FatTreeLink*> parents;
61 /** Virtual link standing for the node global capacity.
64 /** If present, communications from this node to this node will pass through it
65 * instead of passing by an upper level switch.
68 FatTreeNode(sg_platf_cluster_cbarg_t cluster, int id, int level,
74 /** \brief Link in a fat tree.
76 * Represents a single, duplex link in a fat tree. This is necessary to have a tree.
77 * It is equivalent to a physical link.
81 FatTreeLink(sg_platf_cluster_cbarg_t cluster, FatTreeNode *source,
82 FatTreeNode *destination);
83 /** Link going up in the tree */
85 /** Link going down in the tree */
87 /** Upper end of the link */
89 /** Lower end of the link */
90 FatTreeNode *downNode;
95 * \class AsClusterFatTree
97 * \brief Fat tree representation and routing.
99 * Generate fat trees according to the topology asked for. Almost everything
100 * is based on the work of Eitan Zahavi in "D-Mod-K Routing Providing
101 * Non-Blocking Traffic for Shift Permutations on Real Life Fat Trees" (2010).
103 * The exact topology is described in the mandatory topo_parameters
104 * field, and follow the "h ; m_h, ..., m_1 ; w_h, ..., w_1 ; p_h, ..., p_1" format.
105 * h stands for the switches levels number, i.e. the fat tree is of height h,
106 * without the processing nodes. m_i stands for the number of lower level nodes
107 * connected to a node in level i. w_i stands for the number of upper levels
108 * nodes connected to a node in level i-1. p_i stands for the number of
109 * parallel links connecting two nodes between level i and i - 1. Level h is
110 * the topmost switch level, level 1 is the lowest switch level, and level 0
111 * represents the processing nodes. The number of provided nodes must be exactly
112 * the number of processing nodes required to fit the topology, which is the
113 * product of the m_i's.
115 * Routing is made using a destination-mod-k scheme.
117 class XBT_PRIVATE AsClusterFatTree : public AsCluster {
121 virtual void getRouteAndLatency(NetCard *src, NetCard *dst,
122 sg_platf_route_cbarg_t into,
123 double *latency) override;
125 /** \brief Generate the fat tree
127 * Once all processing nodes have been added, this will make sure the fat
128 * tree is generated by calling generateLabels(), generateSwitches() and
129 * then connection all nodes between them, using their label.
131 virtual void create_links();
132 /** \brief Read the parameters in topo_parameters field.
134 * It will also store the cluster for future use.
136 void parse_specific_arguments(sg_platf_cluster_cbarg_t cluster);
137 void addProcessingNode(int id);
138 void generateDotFile(const std::string& filename = "fatTree.dot") const;
142 //description of a PGFT (TODO : better doc)
144 std::vector<unsigned int> lowerLevelNodesNumber; // number of children by node
145 std::vector<unsigned int> upperLevelNodesNumber; // number of parents by node
146 std::vector<unsigned int> lowerLevelPortsNumber; // ports between each level l and l-1
148 std::map<int, FatTreeNode*> computeNodes;
149 std::vector<FatTreeNode*> nodes;
150 std::vector<FatTreeLink*> links;
151 std::vector<unsigned int> nodesByLevel;
153 sg_platf_cluster_cbarg_t cluster;
155 void addLink(FatTreeNode *parent, unsigned int parentPort,
156 FatTreeNode *child, unsigned int childPort);
157 int getLevelPosition(const unsigned int level);
158 void generateLabels();
159 void generateSwitches();
160 int connectNodeToParents(FatTreeNode *node);
161 bool areRelated(FatTreeNode *parent, FatTreeNode *child);
162 bool isInSubTree(FatTreeNode *root, FatTreeNode *node);