]> AND Private Git Repository - loba.git/blobdiff - process.cpp
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Add platforms with 4096 nodes.
[loba.git] / process.cpp
index 57c06612ad84bb9cffaa07123e8c113b0148fad9..b5531b0ce85eff0a0a20f6f5f9ce3a1276a71d5d 100644 (file)
@@ -1,6 +1,8 @@
 #include <algorithm>
 #include <algorithm>
-#include <tr1/functional>
+#include <cmath>
+#include <functional>
 #include <iterator>
 #include <iterator>
+#include <numeric>
 #include <stdexcept>
 #include <sstream>
 #include <xbt/log.h>
 #include <stdexcept>
 #include <sstream>
 #include <xbt/log.h>
@@ -14,15 +16,43 @@ XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(proc);
 
 #include "process.h"
 
 
 #include "process.h"
 
+mutex_t *process::proc_mutex;
+
 double process::total_load_init = 0.0;
 double process::total_load_running = 0.0;
 double process::total_load_exit = 0.0;
 
 double process::total_load_init = 0.0;
 double process::total_load_running = 0.0;
 double process::total_load_exit = 0.0;
 
+int process::process_counter = 0;
+double process::total_load_average;
+double process::average_load_ratio;
+double process::load_diff_threshold;
+
+std::atomic<int> process::convergence_counter(0);
+
+namespace {
+
+    void sleep_until_date(double& date, double duration)
+    {
+        double sleep_duration = date - MSG_get_clock();
+        if (sleep_duration > 0.0)
+            MSG_process_sleep(sleep_duration);
+        date = MSG_get_clock() + duration;
+    }
+
+}
+
 process::process(int argc, char* argv[])
 {
     if (argc < 2 || !(std::istringstream(argv[1]) >> real_load))
         throw std::invalid_argument("bad or missing initial load parameter");
 
 process::process(int argc, char* argv[])
 {
     if (argc < 2 || !(std::istringstream(argv[1]) >> real_load))
         throw std::invalid_argument("bad or missing initial load parameter");
 
+    double iload = std::trunc(real_load);
+    if (opt::integer_transfer && real_load != iload) {
+        XBT_WARN("Initial load %g is not an integer.  Truncate it.",
+                 real_load);
+        real_load = iload;
+    }
+
     neigh.assign(argv + 2, argv + argc);
 
     pneigh.reserve(neigh.size());
     neigh.assign(argv + 2, argv + argc);
 
     pneigh.reserve(neigh.size());
@@ -33,18 +63,36 @@ process::process(int argc, char* argv[])
         rev_neigh.insert(std::make_pair(host, ptr));
     }
 
         rev_neigh.insert(std::make_pair(host, ptr));
     }
 
-    comp = 0.0;
-
     prev_load_broadcast = -1;   // force sending of load on first send_all()
     expected_load = real_load;
     prev_load_broadcast = -1;   // force sending of load on first send_all()
     expected_load = real_load;
-    total_load_running += real_load;
+    received_load = 0.0;
+
+    idle_duration = 0.0;
+    convergence = -1.0;
+
+    proc_mutex->acquire();
+    process_counter++;
+    convergence_counter++;
     total_load_init += real_load;
     total_load_init += real_load;
+    total_load_running += real_load;
+    total_load_average = total_load_running / process_counter;
+    if (opt::avg_load_ratio >= 0.0)
+        average_load_ratio = opt::avg_load_ratio;
+    else
+        average_load_ratio = 100.0 *
+            (process_counter / -opt::avg_load_ratio) / total_load_average;
+    load_diff_threshold = (opt::load_ratio_threshold +
+                           average_load_ratio * total_load_average) / 100.0;
+    proc_mutex->release();
 
     ctrl_close_pending = data_close_pending = neigh.size();
     close_received = false;
     finalizing = false;
 
 
     ctrl_close_pending = data_close_pending = neigh.size();
     close_received = false;
     finalizing = false;
 
-    comp_iter = lb_iter = 0;
+    all_comp_iter = comp_iter = lb_iter = 0;
+
+    lb_thread = new_msg_thread("loba",
+                               std::bind(&process::load_balance_loop, this));
 
     e_xbt_log_priority_t logp = xbt_log_priority_verbose;
     if (!LOG_ISENABLED(logp))
 
     e_xbt_log_priority_t logp = xbt_log_priority_verbose;
     if (!LOG_ISENABLED(logp))
@@ -55,283 +103,432 @@ process::process(int argc, char* argv[])
         oss << ESSE(neigh.size()) << ": ";
         std::transform(neigh.begin(), neigh.end() - 1,
                        std::ostream_iterator<const char*>(oss, ", "),
         oss << ESSE(neigh.size()) << ": ";
         std::transform(neigh.begin(), neigh.end() - 1,
                        std::ostream_iterator<const char*>(oss, ", "),
-                       std::tr1::mem_fn(&neighbor::get_name));
+                       std::mem_fn(&neighbor::get_name));
         oss << neigh.back().get_name();
     }
         oss << neigh.back().get_name();
     }
-    LOG1(logp, "Got %s.", oss.str().c_str());
+    XBT_LOG(logp, "Got %s.", oss.str().c_str());
     print_loads(false, logp);
 }
 
 process::~process()
 {
     print_loads(false, logp);
 }
 
 process::~process()
 {
+    delete lb_thread;
+    proc_mutex->acquire();
     total_load_exit += real_load;
     total_load_exit += real_load;
-    if (opt::bookkeeping) {
-        INFO4("Final load after %d:%d iterations: %g ; expected: %g",
-              lb_iter, comp_iter, real_load, expected_load);
-    } else {
-        INFO2("Final load after %d iterations: %g",
-              lb_iter, real_load);
-        if (lb_iter != comp_iter)
-            WARN2("lb_iter (%d) and comp_iter (%d) differ!",
-                  lb_iter, comp_iter);
-    }
-    VERB1("Total computation for this process: %g", comp);
+    proc_mutex->release();
+    xbt_assert(received_load == 0.0,
+               "received_load is %g, but should be 0.0 !", received_load);
+    if (opt::log_rate < 0)
+        return;
+    XBT_INFO("Final load after %d:%d:%d iterations: %g",
+             lb_iter, comp_iter, all_comp_iter, real_load);
+    if (convergence >= 0.0)
+        XBT_INFO("Convergence within %g%% was achieved at time %g",
+                 average_load_ratio, convergence);
+    else
+        XBT_INFO("Convergence within %g%% was not achieved",
+                 average_load_ratio);
+    XBT_VERB("Expected load was: %g", expected_load);
+    XBT_VERB("Total computation for this process: %g", get_comp_amount());
+    print_loads(true, xbt_log_priority_debug);
+}
+
+double process::get_iter_deviation() const
+{
+    double average_cost = opt::comp_cost(total_load_average); // fixme: get locked?
+    // Do not count idle periods
+    double comp_iter_opt = acc.comp_amount / average_cost;
+/*
+    // Add iterations that could have been achieved while beeing idle
+    // (kept for documentation)
+    double self_speed = MSG_get_host_speed(MSG_host_self());
+    double average_duration = average_cost / self_speed;
+    comp_iter_opt += idle_duration / average_duration;
+*/
+    return comp_iter - comp_iter_opt;
 }
 
 int process::run()
 {
 }
 
 int process::run()
 {
-    double next_iter_after_date = 0.0;
-    INFO1("Initial load: %g", real_load);
-    VERB0("Starting...");
-    while (true) {
-        if (get_load() > 0.0) {
-            double now = MSG_get_clock();
-            if (now < next_iter_after_date)
-                MSG_process_sleep(next_iter_after_date - now);
-            next_iter_after_date = MSG_get_clock() + opt::min_iter_duration;
+    if (opt::log_rate >= 0) {
+        XBT_INFO("Initial load: %g", real_load);
+        XBT_VERB("Initial expected load: %g", expected_load);
+    }
+    XBT_VERB("Starting...");
+    mutex.acquire();
+    lb_thread->start();
+    while (lb_iter <= opt::comp_iter_delay)
+        cond.wait(mutex);
+    mutex.release();
+    double sleep_duration = opt::comp_time_delay - MSG_get_clock();
+    if (sleep_duration > 0.0)
+        MSG_process_sleep(sleep_duration);
+    compute_loop();
+    lb_thread->wait();
+    XBT_VERB("Done.");
+    return 0;
+}
+
+void process::load_balance_loop()
+{
+    using std::placeholders::_1;
 
 
+    double next_iter_after_date = MSG_get_clock() + opt::min_lb_iter_duration;
+    while (still_running()) {
+        if (lb_iter == opt::comp_iter_delay) {
+            mutex.acquire();
+            ++lb_iter;
+            cond.signal();
+            mutex.release();
+        } else {
             ++lb_iter;
             ++lb_iter;
+        }
 
 
-            if (opt::log_rate && lb_iter % opt::log_rate == 0) {
-                if (opt::bookkeeping)
-                    INFO4("(%u:%u) current load: %g ; expected: %g",
-                          lb_iter, comp_iter, real_load, expected_load);
-                else
-                    INFO2("(%u) current load: %g",
-                          lb_iter, real_load);
-            }
+        ctrl_receive(0.0);
 
 
-            load_balance();
+        mutex.acquire();
+        if (!opt::bookkeeping)
+            expected_load = real_load - get_sum_of_to_send();
+        // nothing to do with opt::bookkeeping
 
 
-            print_loads(true, xbt_log_priority_debug);
+        if (opt::log_rate && lb_iter % opt::log_rate == 0) {
+            XBT_INFO("(%u:%u:%u) current load: %g",
+                     lb_iter, comp_iter, all_comp_iter, real_load);
+            XBT_VERB("... expected load: %g", expected_load);
         }
 
         }
 
-        // send load information, and load (data) if any
-        send_all();
-        if (real_load > 0.0) {
-            ++comp_iter;
-            compute();
-        }
+        if (expected_load > 0.0)
+            load_balance();
 
 
-        if (opt::lb_maxiter && lb_iter >= opt::lb_maxiter) {
-            VERB2("Reached lb_maxiter: %d/%d", lb_iter, opt::lb_maxiter);
-            break;
-        }
-        if (opt::comp_maxiter && comp_iter >= opt::comp_maxiter) {
-            VERB2("Reached comp_maxiter: %d/%d", comp_iter, opt::comp_maxiter);
-            break;
+        print_loads(true, xbt_log_priority_debug);
+
+        // send
+        comm.ctrl_flush(false);
+        std::for_each(neigh.begin(), neigh.end(),
+                      std::bind(&process::ctrl_send, this, _1));
+        prev_load_broadcast = expected_load;
+        mutex.release();
+
+        sleep_until_date(next_iter_after_date, opt::min_lb_iter_duration);
+    }
+
+    XBT_VERB("Going to finalize for %s...", __func__);
+    XBT_DEBUG("send CTRL_CLOSE to %zu neighbor%s",
+              neigh.size(), ESSE(neigh.size()));
+    std::for_each(neigh.begin(), neigh.end(),
+                  std::bind(&process::ctrl_close, this, _1));
+    while (ctrl_close_pending) {
+        comm.ctrl_flush(false);
+        XBT_DEBUG("waiting for %d CTRL_CLOSE", ctrl_close_pending);
+        ctrl_receive(-1.0);
+    }
+    comm.ctrl_flush(true);
+}
+
+void process::compute_loop()
+{
+    using std::placeholders::_1;
+
+    double next_iter_after_date = MSG_get_clock() + opt::min_comp_iter_duration;
+    double idle_since_date = 0.0;
+    while (still_running()) {
+        // receive
+        // if there is something to compute, do not block
+        // else, block the duration of an *lb* iteration
+        data_receive(real_load > 0.0 ? 0.0 : opt::min_lb_iter_duration);
+
+        // send
+        comm.data_flush(false);
+        mutex.acquire();
+        real_load += received_load;
+        received_load = 0.0;
+        std::for_each(neigh.begin(), neigh.end(),
+                      std::bind(&process::data_send, this, _1));
+        mutex.release();
+
+        ++all_comp_iter;
+        if (real_load == 0.0)
+            continue;
+
+        convergence_check();
+
+        // compute
+        idle_duration += MSG_get_clock() - idle_since_date;
+        ++comp_iter;
+        double flops = opt::comp_cost(real_load);
+        m_task_t task = MSG_task_create("computation", flops, 0.0, NULL);
+        TRACE_msg_set_task_category(task, TRACE_CAT_COMP);
+        XBT_DEBUG("compute %g flop%s", flops, ESSE(flops));
+        MSG_task_execute(task);
+        add_comp_amount(flops);
+        MSG_task_destroy(task);
+
+        idle_since_date = MSG_get_clock();
+
+        sleep_until_date(next_iter_after_date, opt::min_comp_iter_duration);
+    }
+
+    XBT_VERB("Going to finalize for %s...", __func__);
+    // Note: idle duration is not counted during finalization
+    finalizing = true;
+    XBT_DEBUG("send DATA_CLOSE to %zu neighbor%s",
+              neigh.size(), ESSE(neigh.size()));
+    std::for_each(neigh.begin(), neigh.end(),
+                  std::bind(&process::data_close, this, _1));
+    while (data_close_pending) {
+        comm.data_flush(false);
+        XBT_DEBUG("waiting for %d DATA_CLOSE", data_close_pending);
+        data_receive(-1.0);
+    }
+    real_load += received_load;
+    received_load = 0.0;
+    proc_mutex->acquire();
+    total_load_running -= real_load;
+    proc_mutex->release();
+    convergence_check();
+    comm.data_flush(true);
+}
+
+void process::convergence_check()
+{
+    double average = total_load_average; // fixme: get locked?
+    double load_diff = std::fabs(real_load - average);
+    bool converged = load_diff <= load_diff_threshold;
+
+    if (converged) {
+        if (convergence < 0) {
+            XBT_VERB("current load has converged: %g (%.4g%%)",
+                     real_load,  100.0 * load_diff / average);
+            convergence = MSG_get_clock();
+            local_convergence_counter = opt::exit_on_convergence;
         }
         }
-        if (opt::time_limit && MSG_get_clock() >= opt::time_limit) {
-            VERB2("Reached time limit: %g/%g", MSG_get_clock(), opt::time_limit);
-            break;
+        if (local_convergence_counter > 0 && --local_convergence_counter == 0)
+                --convergence_counter;
+    } else {
+        if (convergence >= 0.0) {
+            XBT_VERB("current load has diverged: %g (%.4g%%)",
+                     real_load, 100.0 * load_diff / average);
+            convergence = -1.0;
+            if (local_convergence_counter == 0)
+                ++convergence_counter;
         }
         }
+    }
+}
 
 
-        // block on receiving unless there is something to compute or
-        // to send
-        double timeout;
-        if (real_load != 0 || get_load() != prev_load_broadcast)
-            timeout = 0.0;
-        else if (opt::min_iter_duration)
-            timeout = opt::min_iter_duration;
-        else
-            timeout = 1.0;
-        receive(timeout);
+bool process::still_running()
+{
+    static bool last_status = true;
 
 
-        // one of our neighbor is finalizing
-        if (opt::exit_on_close && close_received) {
-            VERB0("Close received");
-            break;
-        }
+    if (!last_status) {
+        /* nop */
 
 
-        // have no load and cannot receive anything
-        if (real_load == 0.0 && !may_receive()) {
-            VERB0("I'm a poor lonesome process, and I have no load...");
-            break;
-        }
+    } else if (opt::exit_request) {
+        XBT_VERB("Global exit requested");
+        last_status = false;
+
+    } else if (opt::time_limit && MSG_get_clock() >= opt::time_limit) {
+        XBT_VERB("Reached time limit: %g/%g", MSG_get_clock(), opt::time_limit);
+        last_status = false;
 
 
+    } else if (opt::lb_maxiter && lb_iter >= opt::lb_maxiter) {
+        XBT_VERB("Reached lb_maxiter: %d/%d", lb_iter, opt::lb_maxiter);
+        last_status = false;
+
+    } else if (opt::comp_maxiter && comp_iter >= opt::comp_maxiter) {
+        XBT_VERB("Reached comp_maxiter: %d/%d", comp_iter, opt::comp_maxiter);
+        last_status = false;
+
+    } else if (opt::exit_on_convergence && convergence_counter == 0) {
+        XBT_VERB("Global convergence detected");
+        last_status = false;
+
+    } else if (opt::exit_on_close && close_received) {
+        XBT_VERB("Close received");
+        last_status = false;
+
+    } else if (real_load == 0.0 && !data_close_pending) {
+        XBT_VERB("I'm a poor lonesome process, and I have no load...");
+        last_status = false;
+
+    } else if (100.0 * total_load_running / total_load_init <=
+               opt::load_ratio_threshold) { // fixme: get locked?
         // fixme: this check should be implemented with a distributed
         // algorithm, and not a shared global variable!
         // fixme: this check should be implemented with a distributed
         // algorithm, and not a shared global variable!
-        // fixme: should this chunk be moved before call to receive() ?
-        if (100.0 * total_load_running / total_load_init <=
-            opt::load_ratio_threshold) {
-            VERB0("No more load to balance in system.");
-            break;
-        } else {
-            DEBUG1("still %g load to balance, continuing...", total_load_running);
-        }
+        XBT_VERB("No more load to balance in system.");
+        last_status = false;
     }
     }
-    VERB0("Going to finalize...");
-    finalize();
-
-    /* Open Questions :
-     * - definition of load on heterogeneous hosts ?
-     * - how to detect convergence ?
-     * - how to manage link failures ?
-     */
 
 
-    VERB0("Done.");
-    return 0;
+    return last_status;
 }
 
 }
 
-void process::load_balance()
+double process::get_sum_of_to_send() const
 {
 {
-    if (lb_iter == 1)           // warn only once
-        WARN0("process::load_balance() is a no-op!");
+    using std::placeholders::_1;
+    using std::placeholders::_2;
+
+    return std::accumulate(neigh.begin(), neigh.end(), 0.0,
+                           std::bind(std::plus<double>(), _1,
+                                     std::bind(&neighbor::get_to_send, _2)));
 }
 
 }
 
-void process::compute()
+void process::load_balance()
 {
 {
-    if (real_load > 0.0) {
-        double flops = opt::comp_cost(real_load);
-        m_task_t task = MSG_task_create("computation", flops, 0.0, NULL);
-        TRACE_msg_set_task_category(task, TRACE_CAT_COMP);
-        DEBUG2("compute %g flop%s", flops, ESSE(flops));
-        MSG_task_execute(task);
-        comp += flops;
-        MSG_task_destroy(task);
-    } else {
-        DEBUG0("nothing to compute !");
-    }
+    if (lb_iter == 1)           // warn only once
+        XBT_WARN("process::load_balance() is a no-op!");
 }
 
 void process::send(neighbor& nb, double amount)
 {
 }
 
 void process::send(neighbor& nb, double amount)
 {
-    set_load(get_load() - amount);
+    expected_load -= amount;
     nb.set_to_send(nb.get_to_send() + amount);
     nb.set_to_send(nb.get_to_send() + amount);
-    nb.set_load(nb.get_load() + amount); // fixme: make this optional?
+    nb.set_load(nb.get_load() + amount);
 }
 
 }
 
-void process::send1_no_bookkeeping(neighbor& nb)
+void process::ctrl_send(neighbor& nb)
 {
 {
-    if (real_load != prev_load_broadcast)
-        comm.send(nb.get_ctrl_mbox(), new message(message::INFO, real_load));
-    double load_to_send = nb.get_to_send();
-    if (load_to_send > 0.0) {
-        comm.send(nb.get_data_mbox(), new message(message::LOAD, load_to_send));
-        nb.set_to_send(0.0);
+    double info_to_send = expected_load;
+    double debt_to_send;
+    if (opt::bookkeeping) {     // bookkeeping
+        debt_to_send = nb.get_to_send();
+        if (debt_to_send > 0.0) {
+            nb.set_to_send(0.0);
+            nb.set_debt(nb.get_debt() + debt_to_send);
+        }
+    } else {                    // !bookkeeping
+        debt_to_send = 0.0;
     }
     }
+    if (info_to_send != prev_load_broadcast || debt_to_send > 0.0) {
+        message* msg = new message(message::CTRL, info_to_send, debt_to_send);
+        add_ctrl_send_mesg(msg->get_size());
+        comm.ctrl_send(nb.get_ctrl_mbox(), msg);
+    }
+}
+
+double process::compute_load_to_send(double desired)
+{
+    if (opt::integer_transfer)
+        desired = std::floor(desired);
+    return desired >= opt::min_transfer_amount ? desired : 0.0;
 }
 
 }
 
-void process::send1_bookkeeping(neighbor& nb)
+void process::data_send(neighbor& nb)
 {
 {
-    if (expected_load != prev_load_broadcast)
-        comm.send(nb.get_ctrl_mbox(),
-                  new message(message::INFO, expected_load));
     double load_to_send;
     double load_to_send;
-    double new_debt;
-    double debt_to_send = nb.get_to_send();
-    if (debt_to_send > 0.0) {
-        comm.send(nb.get_ctrl_mbox(),
-                  new message(message::CREDIT, debt_to_send));
-        nb.set_to_send(0.0);
-        new_debt = nb.get_debt() + debt_to_send;
-    } else {
-        new_debt = nb.get_debt();
+    if (opt::bookkeeping) {     // bookkeeping
+        double excess_load;     // load amount we are able to send
+        if (opt::egocentric)
+            excess_load = std::max(0.0, real_load - expected_load);
+        else
+            excess_load = real_load;
+
+        double balance;
+        if (nb.get_credit() > 0.0)
+            balance = nb.get_debt() - nb.get_credit();
+        else
+            balance = nb.get_debt();
+        load_to_send = std::min(excess_load,
+                                std::max(0.0, balance));
+
+        // adjust load to send (rounding, truncation, etc.)
+        load_to_send = compute_load_to_send(load_to_send);
+        if (load_to_send > 0.0)
+            nb.set_debt(nb.get_debt() - load_to_send);
+    } else {                    // !bookkeeping
+        load_to_send = compute_load_to_send(nb.get_to_send());
+        if (load_to_send > 0.0)
+            nb.set_to_send(nb.get_to_send() - load_to_send);
     }
     }
-    if (real_load <= new_debt) {
-        load_to_send = real_load;
-        nb.set_debt(new_debt - load_to_send);
-        real_load = 0.0;
-    } else {
-        load_to_send = new_debt;
-        nb.set_debt(0.0);
-        real_load -= load_to_send;
+    real_load -= load_to_send;
+    while (load_to_send > 0.0) {
+        double amount;
+        if (opt::max_transfer_amount)
+            amount = std::min(load_to_send, opt::max_transfer_amount);
+        else
+            amount = load_to_send;
+        message* msg = new message(message::DATA, amount);
+        add_data_send_mesg(msg->get_size());
+        comm.data_send(nb.get_data_mbox(), msg);
+        load_to_send -= amount;
     }
     }
-    if (load_to_send > 0.0)
-        comm.send(nb.get_data_mbox(), new message(message::LOAD, load_to_send));
 }
 
 }
 
-void process::send_all()
+void process::ctrl_close(neighbor& nb)
 {
 {
-    using std::tr1::bind;
-    using std::tr1::placeholders::_1;
+    comm.ctrl_send(nb.get_ctrl_mbox(), new message(message::CTRL_CLOSE, 0.0));
+}
 
 
-    if (opt::bookkeeping) {
-        std::for_each(neigh.begin(), neigh.end(),
-                      bind(&process::send1_bookkeeping, this, _1));
-        prev_load_broadcast = expected_load;
-    } else {
-        std::for_each(neigh.begin(), neigh.end(),
-                      bind(&process::send1_no_bookkeeping, this, _1));
-        prev_load_broadcast = real_load;
-    }
-    comm.flush(false);
+void process::data_close(neighbor& nb)
+{
+    comm.data_send(nb.get_data_mbox(), new message(message::DATA_CLOSE, 0.0));
 }
 
 }
 
-void process::receive(double timeout)
+void process::ctrl_receive(double timeout)
 {
     message* msg;
     m_host_t from;
 
 {
     message* msg;
     m_host_t from;
 
-    DEBUG2("%sblocking receive (%g)", "\0non-" + !timeout, timeout);
-    while (may_receive() && comm.recv(msg, from, timeout)) {
-        switch (msg->get_type()) {
-        case message::INFO: {
-            neighbor* n = rev_neigh[from];
-            n->set_load(msg->get_amount());
-            break;
-        }
-        case message::CREDIT:
-            expected_load += msg->get_amount();
-            break;
-        case message::LOAD: {
-            double ld = msg->get_amount();
-            real_load += ld;
-            if (finalizing)
-                total_load_running -= ld;
-            break;
-        }
-        case message::CTRL_CLOSE:
-            ctrl_close_pending--;
-            close_received = true;
-            break;
-        case message::DATA_CLOSE:
-            data_close_pending--;
-            close_received = true;
-            break;
-        }
-        delete msg;
-        timeout = 0.0;          // only wait on first recv
+    XBT_DEBUG("%sblocking receive on ctrl (%g)", "\0non-" + !timeout, timeout);
+    while (ctrl_close_pending && comm.ctrl_recv(msg, from, timeout)) {
+        if (msg->get_type() != message::CTRL_CLOSE)
+            add_ctrl_recv_mesg(msg->get_size());
+        handle_message(msg, from);
+        timeout = 0.0;
     }
     }
-    comm.flush(false);
 }
 
 }
 
-void process::finalize1(neighbor& nb)
+void process::data_receive(double timeout)
 {
 {
-    comm.send(nb.get_ctrl_mbox(), new message(message::CTRL_CLOSE, 0.0));
-    comm.send(nb.get_data_mbox(), new message(message::DATA_CLOSE, 0.0));
+    message* msg;
+    m_host_t from;
+
+    XBT_DEBUG("%sblocking receive on data (%g)", "\0non-" + !timeout, timeout);
+    while (data_close_pending && comm.data_recv(msg, from, timeout)) {
+        if (msg->get_type() != message::DATA_CLOSE)
+            add_data_recv_mesg(msg->get_size());
+        handle_message(msg, from);
+        timeout = 0.0;
+    }
 }
 
 }
 
-void process::finalize()
+void process::handle_message(message* msg, m_host_t from)
 {
 {
-    using std::tr1::bind;
-    using std::tr1::placeholders::_1;
-
-    finalizing = true;
-    total_load_running -= real_load;
-
-    DEBUG2("send CLOSE to %lu neighbor%s",
-           (unsigned long )neigh.size(), ESSE(neigh.size()));
-    std::for_each(neigh.begin(), neigh.end(),
-                  bind(&process::finalize1, this, _1));
-
-    while (may_receive()) {
-        comm.flush(false);
-        DEBUG2("waiting for %d CTRL and %d DATA CLOSE",
-               ctrl_close_pending, data_close_pending);
-        receive(-1.0);
+    switch (msg->get_type()) {
+    case message::CTRL: {
+        neighbor* n = rev_neigh[from];
+        n->set_load(msg->get_amount() + n->get_to_send());
+        if (opt::bookkeeping) {
+            double credit = msg->get_credit();
+            expected_load += credit;
+            n->set_credit(n->get_credit() + credit);
+        }
+        break;
     }
     }
-
-    comm.flush(true);
+    case message::DATA: {
+        neighbor* n = rev_neigh[from];
+        double ld = msg->get_amount();
+        received_load += ld;
+        n->set_credit(n->get_credit() - ld);
+        break;
+    }
+    case message::CTRL_CLOSE:
+        ctrl_close_pending--;
+        close_received = true;
+        break;
+    case message::DATA_CLOSE:
+        data_close_pending--;
+        close_received = true;
+        break;
+    }
+    delete msg;
 }
 
 #define print_loads_generic(vec, verbose, logp, cat)                    \
     if (_XBT_LOG_ISENABLEDV((*cat), logp)) {                            \
 }
 
 #define print_loads_generic(vec, verbose, logp, cat)                    \
     if (_XBT_LOG_ISENABLEDV((*cat), logp)) {                            \
-        using std::tr1::bind;                                           \
-        using std::tr1::placeholders::_1;                               \
-        XCLOG0(cat, logp, "Neighbor loads:");                           \
+        using std::placeholders::_1;                                    \
+        XBT_XCLOG(cat, logp, "My load: %g (real); %g (expected).  "     \
+                  "Neighbor loads:", real_load, expected_load);         \
         std::for_each(vec.begin(), vec.end(),                           \
         std::for_each(vec.begin(), vec.end(),                           \
-                      bind(&neighbor::print, _1, verbose, logp, cat));  \
+                      std::bind(&neighbor::print, _1, verbose, logp, cat)); \
     } else ((void)0)
 
 void process::print_loads(bool verbose,
     } else ((void)0)
 
 void process::print_loads(bool verbose,