process.cpp

   1 #include "process.h"
   2
   3 #include <algorithm>
   4 #include <tr1/functional>
   5 #include <iterator>
   6 #include <stdexcept>
   7 #include <sstream>
   8 #include <xbt/log.h>
   9 #include <xbt/time.h>
  10 #include "misc.h"
  11 #include "options.h"
  12
  13 XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(simu);
  14
  15 process::process(int argc, char* argv[])
  16 {
  17     if (argc < 2 || !(std::istringstream(argv[1]) >> load))
  18         throw std::invalid_argument("bad or missing initial load");
  19
  20     neigh.assign(argv + 2, argv + argc);
  21
  22     std::for_each(neigh.begin(), neigh.end(),
  23                   std::tr1::bind(&process::insert_neighbor_in_map,
  24                                  this, std::tr1::placeholders::_1));
  25
  26     expected_load = load;
  27
  28     ctrl_close_pending = data_close_pending = neigh.size();
  29     if (neigh.size() == 1) {
  30         comm.next_close_on_ctrl_is_last();
  31         comm.next_close_on_data_is_last();
  32     }
  33     if (neigh.size() > 0)
  34         comm.listen();
  35
  36     e_xbt_log_priority_t logp = xbt_log_priority_verbose;
  37     if (!LOG_ISENABLED(logp))
  38         return;
  39     std::ostringstream oss;
  40     oss << neigh.size() << " neighbor";
  41     if (!neigh.empty()) {
  42         oss << ESSE(neigh.size()) << ": ";
  43         std::transform(neigh.begin(), neigh.end() - 1,
  44                        std::ostream_iterator<const char*>(oss, ", "),
  45                        std::tr1::mem_fn(&neighbor::get_name));
  46         oss << neigh.back().get_name();
  47     }
  48     LOG1(logp, "Got %s.", oss.str().c_str());
  49     print_loads(logp);
  50 }
  51
  52 process::~process()
  53 {
  54 }
  55
  56 int process::run()
  57 {
  58     bool one_more = true;
  59
  60     INFO1("Initial load: %g", load);
  61     VERB0("Starting...");
  62     iter = 0;
  63     while (one_more) {
  64         ++iter;
  65
  66         if (opt::log_rate && iter % opt::log_rate == 0) {
  67             if (opt::bookkeeping)
  68                 INFO3("(%u) current load: %g ; expected: %g",
  69                       iter, load, expected_load);
  70             else
  71                 INFO2("(%u) current load: %g",
  72                       iter, load);
  73         }
  74
  75         compute();
  76
  77         bool close_received = !receive(false);
  78
  79         if (opt::bookkeeping)
  80             expected_load -= load_balance(expected_load);
  81         else
  82             load -= load_balance(load);
  83
  84         send();
  85         comm.flush(false);
  86
  87         if (opt::exit_on_close && close_received)
  88             one_more = false;
  89         if (opt::maxiter && iter >= opt::maxiter)
  90             one_more = false;
  91     }
  92     VERB0("Going to finalize...");
  93     finalize();
  94
  95     /* Open Questions :
  96      * - definition of load on heterogeneous hosts ?
  97      * - how to detect convergence ?
  98      * - how to manage link failures ?
  99      */
 100
 101     VERB0("Done.");
 102     if (opt::bookkeeping)
 103         INFO4("Final load after %d iteration%s: %g ; expected: %g",
 104               iter, ESSE(iter), load, expected_load);
 105     else
 106         INFO3("Final load after %d iteration%s: %g", iter, ESSE(iter), load);
 107     return 0;
 108 }
 109
 110 void process::compute()
 111 {
 112     // fixme: shall we do something special when duration is 0 ?
 113     double duration = opt::comp_cost(load);
 114     m_task_t task = MSG_task_create("computation", duration, 0.0, NULL);
 115     DEBUG2("compute %g flop%s.", duration, ESSE(duration));
 116     MSG_task_execute(task);
 117     MSG_task_destroy(task);
 118 }
 119
 120 double process::load_balance(double /*my_load*/)
 121 {
 122     return 0.0;
 123 }
 124
 125 void process::send1_no_bookkeeping(neighbor& nb)
 126 {
 127     comm.send(nb.get_ctrl_mbox(), new message(message::INFO, load));
 128     double load_to_send = nb.get_to_send();
 129     if (load_to_send > 0.0) {
 130         comm.send(nb.get_data_mbox(), new message(message::LOAD, load_to_send));
 131         nb.set_to_send(0.0);
 132     }
 133 }
 134
 135 void process::send1_bookkeeping(neighbor& nb)
 136 {
 137     comm.send(nb.get_ctrl_mbox(), new message(message::INFO, expected_load));
 138     double load_to_send;
 139     double new_debt;
 140     double debt_to_send = nb.get_to_send();
 141     if (debt_to_send > 0.0) {
 142         comm.send(nb.get_ctrl_mbox(),
 143                   new message(message::CREDIT, debt_to_send));
 144         nb.set_to_send(0.0);
 145         new_debt = nb.get_debt() + debt_to_send;
 146     } else {
 147         new_debt = nb.get_debt();
 148     }
 149     if (load <= new_debt) {
 150         load_to_send = load;
 151         nb.set_debt(new_debt - load_to_send);
 152         load = 0.0;
 153     } else {
 154         load_to_send = new_debt;
 155         nb.set_debt(0.0);
 156         load -= load_to_send;
 157     }
 158     if (load_to_send > 0.0)
 159         comm.send(nb.get_data_mbox(), new message(message::LOAD, load_to_send));
 160 }
 161
 162 void process::send()
 163 {
 164     // fixme: shall we send data at all iterations?
 165     if (opt::bookkeeping) {
 166         std::for_each(neigh.begin(), neigh.end(),
 167                       std::tr1::bind(&process::send1_bookkeeping,
 168                                      this, std::tr1::placeholders::_1));
 169     } else {
 170         std::for_each(neigh.begin(), neigh.end(),
 171                       std::tr1::bind(&process::send1_no_bookkeeping,
 172                                      this, std::tr1::placeholders::_1));
 173     }
 174 }
 175
 176 // Returns false if a CLOSE message was received.
 177 bool process::receive(bool wait_for_close)
 178 {
 179     bool result = true;
 180     message* msg;
 181     m_host_t from;
 182     while ((ctrl_close_pending ||
 183             data_close_pending) && comm.recv(msg, from, wait_for_close)) {
 184         DEBUG2("received %s from %s",
 185                msg->to_string().c_str(), MSG_host_get_name(from));
 186         switch (msg->get_type()) {
 187         case message::INFO: {
 188             neighbor* n = rev_neigh[from];
 189             n->set_load(msg->get_amount());
 190             break;
 191         }
 192         case message::CREDIT:
 193             expected_load += msg->get_amount();
 194             break;
 195         case message::LOAD:
 196             load += msg->get_amount();
 197             break;
 198         case message::CTRL_CLOSE:
 199             if (--ctrl_close_pending == 1)
 200                 comm.next_close_on_ctrl_is_last();
 201             DEBUG1("ctrl_close_pending = %d", ctrl_close_pending);
 202             result = false;
 203             break;
 204         case message::DATA_CLOSE:
 205             if (--data_close_pending == 1)
 206                 comm.next_close_on_data_is_last();
 207             DEBUG1("data_close_pending = %d", data_close_pending);
 208             result = false;
 209             break;
 210         }
 211         delete msg;
 212     }
 213     return result;
 214 }
 215
 216 void process::finalize1(neighbor& nb)
 217 {
 218     comm.send(nb.get_ctrl_mbox(), new message(message::CTRL_CLOSE, 0.0));
 219     comm.send(nb.get_data_mbox(), new message(message::DATA_CLOSE, 0.0));
 220 }
 221
 222 void process::finalize()
 223 {
 224     DEBUG2("send CLOSE to %d neighbor%s.",
 225            (int )neigh.size(), ESSE(neigh.size()));
 226     std::for_each(neigh.begin(), neigh.end(),
 227                   std::tr1::bind(&process::finalize1,
 228                                  this, std::tr1::placeholders::_1));
 229
 230     DEBUG2("wait for CLOSE from %d neighbor%s.",
 231            (int )neigh.size(), ESSE(neigh.size()));
 232     receive(true);
 233
 234     comm.flush(true);
 235 }
 236
 237 void process::print_loads(e_xbt_log_priority_t logp)
 238 {
 239     if (!LOG_ISENABLED(logp))
 240         return;
 241
 242     std::ostringstream oss;
 243     if (neigh.empty()) {
 244         oss << "no neighbor!";
 245     } else {
 246         std::transform(neigh.begin(), neigh.end() - 1,
 247                        std::ostream_iterator<double>(oss, ", "),
 248                        std::tr1::mem_fn(&neighbor::get_load));
 249         oss << neigh.back().get_load();
 250     }
 251     LOG1(logp, "Neighbor loads: %s", oss.str().c_str());
 252 }
 253
 254 void process::insert_neighbor_in_map(neighbor& nb)
 255 {
 256     neighbor* nbp = &nb;
 257     m_host_t host = MSG_get_host_by_name(nb.get_name());
 258     rev_neigh.insert(std::make_pair(host, nbp));
 259 }
 260
 261 // Local variables:
 262 // mode: c++
 263 // End: