1 /* Copyright (c) 2014. 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 #include "surf_routing_cluster.hpp"
9 #ifndef SURF_ROUTING_CLUSTER_FAT_TREE_HPP_
10 #define SURF_ROUTING_CLUSTER_FAT_TREE_HPP_
13 /** \file surf_routing_cluster_fat_tree.cpp
14 * The class AsClusterFatTree describes PGFT, as introduced by Eitan Zahavi
15 * in "D-Mod-K Routing Providing Non-Blocking Traffic for Shift Permutations
16 * on Real Life Fat Trees" (2010). RLFT are PGFT with some restrictions to
17 * address real world constraints, which are not currently enforced.
23 /** \brief A node in a fat tree.
24 * A FatTreeNode can either be a switch or a processing node. Switches are
25 * identified by a negative ID. This class is closely related to fat
29 /** Unique ID which identifies every node. */
31 /* Level into the tree, with 0 being the leafs.
34 /* \brief Position into the level, starting from 0.
36 unsigned int position;
37 /** In order to link nodes between them, each one must be assigned a label,
38 * consisting of l integers, l being the levels number of the tree. Each label
39 * is unique in the level, and the way it is generated allows the construction
40 * of a fat tree which fits the desired topology.
42 std::vector<unsigned int> label;
44 /** Links to the lower level, where the position in the vector corresponds to
47 std::vector<FatTreeLink*> children;
48 /** Links to the upper level, where the position in the vector corresponds to
51 std::vector<FatTreeLink*> parents;
53 /** Virtual link standing for the node global capacity.
55 NetworkLink* limiterLink;
56 /** If present, communications from this node to this node will pass through it
57 * instead of passing by an upper level switch.
59 NetworkLink* loopback;
60 FatTreeNode(sg_platf_cluster_cbarg_t cluster, int id, int level,
66 /** \brief Link in a fat tree.
68 * Represents a single, duplex link in a fat tree. This is necessary to have a tree.
69 * It is equivalent to a physical link.
73 FatTreeLink(sg_platf_cluster_cbarg_t cluster, FatTreeNode *source,
74 FatTreeNode *destination);
75 /** Link going up in the tree
78 /** Link going down in the tree
80 NetworkLink *downLink;
81 /** Upper end of the link
84 /** Lower end of the link
86 FatTreeNode *downNode;
90 /** \brief Fat tree representation and routing.
92 * Generate fat trees according to the topology asked for. Almost everything
93 * is based on the work of Eitan Zahavi in "D-Mod-K Routing Providing
94 * Non-Blocking Traffic for Shift Permutations on Real Life Fat Trees" (2010).
96 * The exact topology is described in the mandatory topo_parameters
97 * field, and follow the "h ; m_h, ..., m_1 ; w_h, ..., w_1 ; p_h, ..., p_1" format.
98 * h stands for the switches levels number, i.e. the fat tree is of height h,
99 * without the processing nodes. m_i stands for the number of lower level nodes
100 * connected to a node in level i. w_i stands for the number of upper levels
101 * nodes connected to a node in level i-1. p_i stands for the number of
102 * parallel links connecting two nodes between level i and i - 1. Level h is
103 * the topmost switch level, level 1 is the lowest switch level, and level 0
104 * represents the processing nodes. The number of provided nodes must be exactly
105 * the number of processing nodes required to fit the topology, which is the
106 * product of the m_i's.
108 * Routing is made using a destination-mod-k scheme.
110 class AsClusterFatTree : public AsCluster {
114 virtual void getRouteAndLatency(RoutingEdgePtr src, RoutingEdgePtr dst,
115 sg_platf_route_cbarg_t into,
118 /** \brief Generate the fat tree
120 * Once all processing nodes have been added, this will make sure the fat
121 * tree is generated by calling generateLabels(), generateSwitches() and
122 * then connection all nodes between them, using their label.
124 virtual void create_links();
125 /** \brief Read the parameters in topo_parameters field.
127 * It will also store the cluster for future use.
129 void parse_specific_arguments(sg_platf_cluster_cbarg_t cluster);
130 /** \brief Add a processing node.
132 void addProcessingNode(int id);
133 void generateDotFile(const string& filename = "fatTree.dot") const;
137 //description of a PGFT (TODO : better doc)
139 std::vector<unsigned int> lowerLevelNodesNumber; // number of children by node
140 std::vector<unsigned int> upperLevelNodesNumber; // number of parents by node
141 std::vector<unsigned int> lowerLevelPortsNumber; // ports between each level l and l-1
143 std::map<int, FatTreeNode*> computeNodes;
144 std::vector<FatTreeNode*> nodes;
145 std::vector<FatTreeLink*> links;
146 std::vector<unsigned int> nodesByLevel;
148 sg_platf_cluster_cbarg_t cluster;
150 void addLink(FatTreeNode *parent, unsigned int parentPort,
151 FatTreeNode *child, unsigned int childPort);
152 int getLevelPosition(const unsigned int level);
153 void generateLabels();
154 void generateSwitches();
155 int connectNodeToParents(FatTreeNode *node);
156 bool areRelated(FatTreeNode *parent, FatTreeNode *child);
157 bool isInSubTree(FatTreeNode *root, FatTreeNode *node);