SimGrid  3.13
Versatile Simulation of Distributed Systems
simgrid::surf::AsClusterFatTree Class Reference

Fat tree representation and routing. More...

#include <AsClusterFatTree.hpp>

Inheritance diagram for simgrid::surf::AsClusterFatTree:
simgrid::surf::AsCluster simgrid::surf::AsImpl

Public Member Functions

 AsClusterFatTree (const char *name)
 
 ~AsClusterFatTree ()
 
virtual void getRouteAndLatency (NetCard *src, NetCard *dst, sg_platf_route_cbarg_t into, double *latency) override
 Probe the routing path between two points. More...
 
void seal () override
 Generate the fat tree. More...
 
void parse_specific_arguments (sg_platf_cluster_cbarg_t cluster) override
 Read the parameters in topo_parameters field. More...
 
void addProcessingNode (int id)
 
void generateDotFile (const std::string &filename="fatTree.dot") const
 
- Public Member Functions inherited from simgrid::surf::AsCluster
 AsCluster (const char *name)
 
 ~AsCluster ()
 
void getGraph (xbt_graph_t graph, xbt_dict_t nodes, xbt_dict_t edges) override
 
virtual void create_links_for_node (sg_platf_cluster_cbarg_t cluster, int id, int rank, int position)
 
- Public Member Functions inherited from simgrid::surf::AsImpl
virtual xbt_dynar_t getOneLinkRoutes ()
 retrieves the list of all routes of size 1 (of type src x dst x Link) More...
 
std::vector< surf::Link * > * getBypassRoute (surf::NetCard *src, surf::NetCard *dst)
 

Additional Inherited Members

- Public Types inherited from simgrid::surf::AsImpl
enum  RoutingMode { RoutingMode::unset = 0, RoutingMode::base, RoutingMode::recursive }
 
- Static Public Member Functions inherited from simgrid::surf::AsImpl
static void getRouteRecursive (surf::NetCard *src, surf::NetCard *dst, std::vector< surf::Link * > *links, double *latency)
 Recursive function for getRouteAndLatency. More...
 
- Public Attributes inherited from simgrid::surf::AsCluster
xbt_dynar_t privateLinks_ = xbt_dynar_new(sizeof(s_surf_parsing_link_up_down_t),NULL)
 
Linkbackbone_ = nullptr
 
voidloopback_ = nullptr
 
NetCardrouter_ = nullptr
 
int has_limiter_ = 0
 
int has_loopback_ = 0
 
int nb_links_per_node_ = 1
 
- Public Attributes inherited from simgrid::surf::AsImpl
RoutingMode hierarchy_ = RoutingMode::unset
 
surf::NetCardnetcard_ = nullptr
 
- Protected Member Functions inherited from simgrid::surf::AsImpl
 AsImpl (const char *name)
 
 ~AsImpl ()
 

Detailed Description

Fat tree representation and routing.

Generate fat trees according to the topology asked for. Almost everything is based on the work of Eitan Zahavi in "D-Mod-K Routing Providing Non-Blocking Traffic for Shift Permutations on Real Life Fat Trees" (2010).

The exact topology is described in the mandatory topo_parameters field, and follow the "h ; m_h, ..., m_1 ; w_h, ..., w_1 ; p_h, ..., p_1" format. h stands for the switches levels number, i.e. the fat tree is of height h, without the processing nodes. m_i stands for the number of lower level nodes connected to a node in level i. w_i stands for the number of upper levels nodes connected to a node in level i-1. p_i stands for the number of parallel links connecting two nodes between level i and i - 1. Level h is the topmost switch level, level 1 is the lowest switch level, and level 0 represents the processing nodes. The number of provided nodes must be exactly the number of processing nodes required to fit the topology, which is the product of the m_i's.

Routing is made using a destination-mod-k scheme.

Constructor & Destructor Documentation

simgrid::surf::AsClusterFatTree::AsClusterFatTree ( const char *  name)
simgrid::surf::AsClusterFatTree::~AsClusterFatTree ( )

Member Function Documentation

void simgrid::surf::AsClusterFatTree::getRouteAndLatency ( NetCard src,
NetCard dst,
sg_platf_route_cbarg_t  into,
double *  latency 
)
overridevirtual

Probe the routing path between two points.

The networking model uses this function when creating a communication to retrieve both the list of links that the create communication will use, and the summed latency that these links represent.

The network could recompute the latency by itself from the list, but it would require an additional link set traversal. This operation being on the critical path of SimGrid, the routing computes the latency in behalf of the network.

Things are rather complex here because we have to find the path from ASes to ASes, and within each. In addition, the different ASes may use differing routing models. Some ASes may be routed in full, others may have only some connection information and use a shortest path on top of that, and so on. Some ASes may even not have any predefined links and use only coordinate informations to compute the latency.

So, the path is constructed recursively, with each traversed AS adding its information to the set. The algorithm for that is explained in http://hal.inria.fr/hal-00650233/

Parameters
srcInitial point of the routing path
dstFinal point of the routing path
intoContainer into which the traversed links should be pushed
latencyAccumulator in which the latencies should be added (caller must set it to 0)

Reimplemented from simgrid::surf::AsCluster.

void simgrid::surf::AsClusterFatTree::seal ( )
override

Generate the fat tree.

Once all processing nodes have been added, this will make sure the fat tree is generated by calling generateLabels(), generateSwitches() and then connection all nodes between them, using their label.

void simgrid::surf::AsClusterFatTree::parse_specific_arguments ( sg_platf_cluster_cbarg_t  cluster)
overridevirtual

Read the parameters in topo_parameters field.

It will also store the cluster for future use.

Reimplemented from simgrid::surf::AsCluster.

void simgrid::surf::AsClusterFatTree::addProcessingNode ( int  id)
void simgrid::surf::AsClusterFatTree::generateDotFile ( const std::string filename = "fatTree.dot") const

The documentation for this class was generated from the following files: