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sendUntimedData

void sendUntimedData(Request* req);

This function should be used to send requests on a network during SST's untimed phases, init() and complete. This is not a pure virtual function, however, implementing it is recommended per the note below. See SST::Link::sendUntimedData for additional detail on the use of this function.

Requirements​

Network interface  
Must support sending events via this function during SST's init() and complete() phases. During init(). This function is allowed to cause an error if it is called during init() but a call to isNetworkInitialized() would return false.

Endpoint  
May optionally use this function during init() and complete() to send events over the network. Must not call this function during init() until isNetworkInitialized() returns true.

Parameters​

  • returns (Request*) A request if one was received, otherwise nullptr. The caller is responsible for deleting any Request returned.

Parameters​

  • req (Request*) A Request to send
  • returns none

Examples​

Example 1: Supporting sendUntimedData at a network interface​

Excerpt from sst-elements/src/sst/elements/merlin/interfaces/linkControl.cc
void LinkControl::sendUntimedData(SST::Interfaces::SimpleNetwork::Request* req)
{
    if ( use_nid_map ) {
        req->dest = nid_map[req->dest];
    }
    // Send the request on interface's link into the network using merlin's internal RtrEvent type
    rtr_link->sendUntimedData(new RtrEvent(req, id, 0));
}

Example 2: Sending untimed data from an endpoint​

After the network is initialized, the endpoint uses sendUntimedData() to broadcast a message containing the endpoint's name and network ID. The endpoints use these messages to build a map of available network destinations (IDmap).

void Endpoint::init(unsigned int phase) {
    net_iface->init(phase);
    
    bool networkReady = net_iface->isNetworkInitialized();

    if (networkReady) {
        /* Broadcast all the endpoint IDs so the endpoints can send data */
        SST::Interfaces::SimpleNetwork::Request * req = new SST::Interfaces::SimpleNetwork::Request();
        req->dest = SST::Interfaces::SimpleNetwork::INIT_BROADCAST_ADDR; /* Broadcast */
        req->src = net_iface->getEndpointID();
        
        // Create an event with this endpoint's name so the other endpoints can map our ID to our name
        SST::Interfaces::StringEvent* strEv = new SST::Interfaces::StringEvent(getName());
        req->givePayload(strEv);

        net_iface->sendUntimedData(req); 

        while (SST::Interfaces::SimpleNetwork::Request* req = net_iface->recvUntimedData()) {
            /* set up a mapping table of the other endpoints' names -> IDs */
            SST::Interfaces::StringEvent* name = static_cast<SST::Interfaces::StringEvent*>(req->takePayload());
            IDMap.insert(std::make_pair(name->getString(), req->src));
            delete req;
            delete name; /* Have to delete separately from req since we used takePayload() to extract it */
        }
    }
}
#include <sst/core/interfaces/simpleNetwork.h>