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_
12 #include "surf_routing_cluster.hpp"
15 /** \file surf_routing_cluster_fat_tree.cpp
16 * The class AsClusterFatTree describes PGFT, as introduced by Eitan Zahavi
17 * in "D-Mod-K Routing Providing Non-Blocking Traffic for Shift Permutations
18 * on Real Life Fat Trees" (2010). RLFT are PGFT with some restrictions to
19 * address real world constraints, which are not currently enforced.
22 class XBT_PRIVATE FatTreeNode;
23 class XBT_PRIVATE FatTreeLink;
25 /** \brief A node in a fat tree.
26 * A FatTreeNode can either be a switch or a processing node. Switches are
27 * identified by a negative ID. This class is closely related to fat
31 /** Unique ID which identifies every node. */
33 /* Level into the tree, with 0 being the leafs.
36 /* \brief Position into the level, starting from 0.
38 unsigned int position;
39 /** In order to link nodes between them, each one must be assigned a label,
40 * consisting of l integers, l being the levels number of the tree. Each label
41 * is unique in the level, and the way it is generated allows the construction
42 * of a fat tree which fits the desired topology.
44 std::vector<unsigned int> label;
46 /** Links to the lower level, where the position in the vector corresponds to
49 std::vector<FatTreeLink*> children;
50 /** Links to the upper level, where the position in the vector corresponds to
53 std::vector<FatTreeLink*> parents;
55 /** Virtual link standing for the node global capacity.
58 /** If present, communications from this node to this node will pass through it
59 * instead of passing by an upper level switch.
62 FatTreeNode(sg_platf_cluster_cbarg_t cluster, int id, int level,
68 /** \brief Link in a fat tree.
70 * Represents a single, duplex link in a fat tree. This is necessary to have a tree.
71 * It is equivalent to a physical link.
75 FatTreeLink(sg_platf_cluster_cbarg_t cluster, FatTreeNode *source,
76 FatTreeNode *destination);
77 /** Link going up in the tree
80 /** Link going down in the tree
83 /** Upper end of the link
86 /** Lower end of the link
88 FatTreeNode *downNode;
92 /** \brief Fat tree representation and routing.
94 * Generate fat trees according to the topology asked for. Almost everything
95 * is based on the work of Eitan Zahavi in "D-Mod-K Routing Providing
96 * Non-Blocking Traffic for Shift Permutations on Real Life Fat Trees" (2010).
98 * The exact topology is described in the mandatory topo_parameters
99 * field, and follow the "h ; m_h, ..., m_1 ; w_h, ..., w_1 ; p_h, ..., p_1" format.
100 * h stands for the switches levels number, i.e. the fat tree is of height h,
101 * without the processing nodes. m_i stands for the number of lower level nodes
102 * connected to a node in level i. w_i stands for the number of upper levels
103 * nodes connected to a node in level i-1. p_i stands for the number of
104 * parallel links connecting two nodes between level i and i - 1. Level h is
105 * the topmost switch level, level 1 is the lowest switch level, and level 0
106 * represents the processing nodes. The number of provided nodes must be exactly
107 * the number of processing nodes required to fit the topology, which is the
108 * product of the m_i's.
110 * Routing is made using a destination-mod-k scheme.
112 class XBT_PRIVATE AsClusterFatTree : public AsCluster {
116 virtual void getRouteAndLatency(RoutingEdge *src, RoutingEdge *dst,
117 sg_platf_route_cbarg_t into,
120 /** \brief Generate the fat tree
122 * Once all processing nodes have been added, this will make sure the fat
123 * tree is generated by calling generateLabels(), generateSwitches() and
124 * then connection all nodes between them, using their label.
126 virtual void create_links();
127 /** \brief Read the parameters in topo_parameters field.
129 * It will also store the cluster for future use.
131 void parse_specific_arguments(sg_platf_cluster_cbarg_t cluster);
132 /** \brief Add a processing node.
134 void addProcessingNode(int id);
135 void generateDotFile(const string& filename = "fatTree.dot") const;
139 //description of a PGFT (TODO : better doc)
141 std::vector<unsigned int> lowerLevelNodesNumber; // number of children by node
142 std::vector<unsigned int> upperLevelNodesNumber; // number of parents by node
143 std::vector<unsigned int> lowerLevelPortsNumber; // ports between each level l and l-1
145 std::map<int, FatTreeNode*> computeNodes;
146 std::vector<FatTreeNode*> nodes;
147 std::vector<FatTreeLink*> links;
148 std::vector<unsigned int> nodesByLevel;
150 sg_platf_cluster_cbarg_t cluster;
152 void addLink(FatTreeNode *parent, unsigned int parentPort,
153 FatTreeNode *child, unsigned int childPort);
154 int getLevelPosition(const unsigned int level);
155 void generateLabels();
156 void generateSwitches();
157 int connectNodeToParents(FatTreeNode *node);
158 bool areRelated(FatTreeNode *parent, FatTreeNode *child);
159 bool isInSubTree(FatTreeNode *root, FatTreeNode *node);