void P2PSync<Dtype>::run(const vector<device*>& gpus) {
// Pair devices for map-reduce synchronization
vector<DevicePair> pairs;
DevicePair::compute(gpus, &pairs);
ostringstream s;
for (int i = 1; i < pairs.size(); ++i) {
s << (i == 1 ? "" : ", ") << pairs[i].get_parent() << ":"
<< pairs[i].get_device();
}
LOG(INFO)<< "GPUs pairs " << s.str();
SolverParameter param(solver_->param());
vector<shared_ptr<P2PSync<Dtype> > > syncs(gpus.size());
// Build the GPU tree by finding the parent for each solver
for (int attempts = 0; attempts < pairs.size(); ++attempts) {
for (int i = 1; i < pairs.size(); ++i) {
if (!syncs[i].get()) {
P2PSync<Dtype>* parent = NULL;
for (int j = 0; j < syncs.size(); ++j) {
P2PSync<Dtype>* sync = j == 0 ? this : syncs[j].get();
if (sync) {
const SolverParameter& p = sync->solver()->param();
if (p.device_id() == pairs[i].get_parent()->list_id()) {
parent = sync;
}
}
}
if (parent) {
param.set_device_id(pairs[i].get_device()->list_id());
syncs[i].reset(new P2PSync<Dtype>(solver_, parent, param));
parent->children_.push_back((P2PSync<Dtype>*) syncs[i].get());
}
}
}
}
LOG(INFO)<< "Starting Optimization";
for (int i = 1; i < syncs.size(); ++i) {
syncs[i]->StartInternalThread(Caffe::GetDefaultDevice());
}
// Run root solver on current thread
solver_->Solve();
for (int i = 1; i < syncs.size(); ++i) {
syncs[i]->StopInternalThread();
}
}
void P2PSync<Dtype>::Prepare(const vector<int>& gpus,
vector<shared_ptr<P2PSync<Dtype> > >* syncs) {
// Pair devices for map-reduce synchronization
vector<DevicePair> pairs;
DevicePair::compute(gpus, &pairs);
ostringstream s;
for (int i = 1; i < pairs.size(); ++i) {
s << (i == 1 ? "" : ", ") << pairs[i].parent() << ":" << pairs[i].device();
}
LOG(INFO)<< "GPUs pairs " << s.str();
SolverParameter param(solver_->param());
// Build the GPU tree by finding the parent for each solver
for (int attempts = 0; attempts < pairs.size(); ++attempts) {
for (int i = 1; i < pairs.size(); ++i) {
if (!syncs->at(i).get()) {
P2PSync<Dtype>* parent = NULL;
for (int j = 0; j < syncs->size(); ++j) {
P2PSync<Dtype>* sync = j == 0 ? this : syncs->at(j).get();
if (sync) {
const SolverParameter& p = sync->solver()->param();
if (p.device_id() == pairs[i].parent()) {
parent = sync;
}
}
}
if (parent) {
param.set_device_id(pairs[i].device());
syncs->at(i).reset(new P2PSync<Dtype>(solver_, parent, param));
parent->children_.push_back((P2PSync<Dtype>*) syncs->at(i).get());
}
}
}
}
}