+ /* Resume the VM */
+ simcall_vm_resume(ms->vm);
+
+ /* install the affinity setting of the VM on the destination pm */
+ {
+ msg_host_priv_t priv = msg_host_resource_priv(ms->vm);
+
+ unsigned long affinity_mask = (unsigned long) xbt_dict_get_or_null_ext(priv->affinity_mask_db, (char *) ms->dst_pm, sizeof(msg_host_t));
+ simcall_vm_set_affinity(ms->vm, ms->dst_pm, affinity_mask);
+ XBT_INFO("set affinity(0x%04lx@%s) for %s", affinity_mask, MSG_host_get_name(ms->dst_pm), MSG_host_get_name(ms->vm));
+ }
+
+ {
+ char *task_name = get_mig_task_name(ms->vm, ms->src_pm, ms->dst_pm, 4);
+
+ msg_task_t task = MSG_task_create(task_name, 0, 0, NULL);
+ msg_error_t ret = MSG_task_send(task, ms->mbox_ctl);
+ xbt_assert(ret == MSG_OK);
+
+ xbt_free(task_name);
+ }
+
+
+ xbt_free(finalize_task_name);
+
+ XBT_DEBUG("mig: rx_done");
+
+ return 0;
+}
+
+static void reset_dirty_pages(msg_vm_t vm)
+{
+ msg_host_priv_t priv = msg_host_resource_priv(vm);
+
+ char *key = NULL;
+ xbt_dict_cursor_t cursor = NULL;
+ dirty_page_t dp = NULL;
+ xbt_dict_foreach(priv->dp_objs, cursor, key, dp) {
+ double remaining = MSG_task_get_remaining_computation(dp->task);
+ dp->prev_clock = MSG_get_clock();
+ dp->prev_remaining = remaining;
+
+ // XBT_INFO("%s@%s remaining %f", key, sg_host_name(vm), remaining);
+ }
+}
+
+static void start_dirty_page_tracking(msg_vm_t vm)
+{
+ msg_host_priv_t priv = msg_host_resource_priv(vm);
+ priv->dp_enabled = 1;
+
+ reset_dirty_pages(vm);
+}
+
+static void stop_dirty_page_tracking(msg_vm_t vm)
+{
+ msg_host_priv_t priv = msg_host_resource_priv(vm);
+ priv->dp_enabled = 0;
+}
+
+#if 0
+/* It might be natural that we define dp_rate for each task. But, we will also
+ * have to care about how each task behavior affects the memory update behavior
+ * at the operating system level. It may not be easy to model it with a simple algorithm. */
+double calc_updated_pages(char *key, msg_vm_t vm, dirty_page_t dp, double remaining, double clock)
+{
+ double computed = dp->prev_remaining - remaining;
+ double duration = clock - dp->prev_clock;
+ double updated = dp->task->dp_rate * computed;
+
+ XBT_INFO("%s@%s: computated %f ops (remaining %f -> %f) in %f secs (%f -> %f)",
+ key, sg_host_name(vm), computed, dp->prev_remaining, remaining, duration, dp->prev_clock, clock);
+ XBT_INFO("%s@%s: updated %f bytes, %f Mbytes/s",
+ key, sg_host_name(vm), updated, updated / duration / 1000 / 1000);
+
+ return updated;
+}
+#endif
+
+static double get_computed(char *key, msg_vm_t vm, dirty_page_t dp, double remaining, double clock)
+{
+ double computed = dp->prev_remaining - remaining;
+ double duration = clock - dp->prev_clock;
+
+ XBT_DEBUG("%s@%s: computed %f ops (remaining %f -> %f) in %f secs (%f -> %f)",
+ key, sg_host_name(vm), computed, dp->prev_remaining, remaining, duration, dp->prev_clock, clock);
+
+ return computed;
+}
+
+static double lookup_computed_flop_counts(msg_vm_t vm, int stage_for_fancy_debug, int stage2_round_for_fancy_debug)
+{
+ msg_host_priv_t priv = msg_host_resource_priv(vm);
+ double total = 0;
+
+ char *key = NULL;
+ xbt_dict_cursor_t cursor = NULL;
+ dirty_page_t dp = NULL;
+ xbt_dict_foreach(priv->dp_objs, cursor, key, dp) {
+ double remaining = MSG_task_get_remaining_computation(dp->task);
+
+ double clock = MSG_get_clock();
+
+ // total += calc_updated_pages(key, vm, dp, remaining, clock);
+ total += get_computed(key, vm, dp, remaining, clock);
+
+ dp->prev_remaining = remaining;
+ dp->prev_clock = clock;
+ }
+
+ total += priv->dp_updated_by_deleted_tasks;
+
+ XBT_DEBUG("mig-stage%d.%d: computed %f flop_counts (including %f by deleted tasks)",
+ stage_for_fancy_debug,
+ stage2_round_for_fancy_debug,
+ total, priv->dp_updated_by_deleted_tasks);
+
+
+
+ priv->dp_updated_by_deleted_tasks = 0;
+
+
+ return total;
+}
+
+// TODO Is this code redundant with the information provided by
+// msg_process_t MSG_process_create(const char *name, xbt_main_func_t code, void *data, msg_host_t host)
+void MSG_host_add_task(msg_host_t host, msg_task_t task)
+{
+ msg_host_priv_t priv = msg_host_resource_priv(host);
+ double remaining = MSG_task_get_remaining_computation(task);
+ char *key = bprintf("%s-%p", task->name, task);
+
+ dirty_page_t dp = xbt_new0(s_dirty_page, 1);
+ dp->task = task;
+
+ /* It should be okay that we add a task onto a migrating VM. */
+ if (priv->dp_enabled) {
+ dp->prev_clock = MSG_get_clock();
+ dp->prev_remaining = remaining;
+ }
+
+ xbt_assert(xbt_dict_get_or_null(priv->dp_objs, key) == NULL);
+ xbt_dict_set(priv->dp_objs, key, dp, NULL);
+ XBT_DEBUG("add %s on %s (remaining %f, dp_enabled %d)", key, sg_host_name(host), remaining, priv->dp_enabled);
+
+ xbt_free(key);
+}
+
+void MSG_host_del_task(msg_host_t host, msg_task_t task)
+{
+ msg_host_priv_t priv = msg_host_resource_priv(host);
+
+ char *key = bprintf("%s-%p", task->name, task);
+
+ dirty_page_t dp = xbt_dict_get_or_null(priv->dp_objs, key);
+ xbt_assert(dp->task == task);
+
+ /* If we are in the middle of dirty page tracking, we record how much
+ * computation has been done until now, and keep the information for the
+ * lookup_() function that will called soon. */
+ if (priv->dp_enabled) {
+ double remaining = MSG_task_get_remaining_computation(task);
+ double clock = MSG_get_clock();
+ // double updated = calc_updated_pages(key, host, dp, remaining, clock);
+ double updated = get_computed(key, host, dp, remaining, clock);
+
+ priv->dp_updated_by_deleted_tasks += updated;
+ }
+
+ xbt_dict_remove(priv->dp_objs, key);
+ xbt_free(dp);
+
+ XBT_DEBUG("del %s on %s", key, sg_host_name(host));
+
+ xbt_free(key);
+}
+
+
+static int deferred_exec_fun(int argc, char *argv[])
+{
+ xbt_assert(argc == 3);
+ const char *comp_str = argv[1];
+ double computaion = atof(comp_str);
+ const char *prio_str = argv[2];
+ double prio = atof(prio_str);
+
+ msg_task_t task = MSG_task_create("__task_deferred", computaion, 0, NULL);
+ // XBT_INFO("exec deferred %f", computation);
+
+ /* dpt is the results of the VM activity */
+ MSG_task_set_priority(task, prio);
+ MSG_task_execute(task);
+
+
+
+ MSG_task_destroy(task);
+
+ return 0;
+}
+
+static void launch_deferred_exec_process(msg_host_t host, double computation, double prio)
+{
+ char *pr_name = bprintf("__pr_deferred_exec_%s", MSG_host_get_name(host));
+
+ int nargvs = 4;
+ char **argv = xbt_new(char *, nargvs);
+ argv[0] = pr_name;
+ argv[1] = bprintf("%f", computation);
+ argv[2] = bprintf("%f", prio);
+ argv[3] = NULL;
+
+ MSG_process_create_with_arguments(pr_name, deferred_exec_fun, NULL, host, nargvs - 1, argv);
+}
+
+
+static int task_tx_overhead_fun(int argc, char *argv[])
+{
+ xbt_assert(argc == 2);
+ const char *mbox = argv[1];
+
+ int need_exit = 0;
+
+ // XBT_INFO("start %s", mbox);
+
+ for (;;) {
+ msg_task_t task = NULL;
+ MSG_task_recv(&task, mbox);
+
+ // XBT_INFO("task->name %s", task->name);
+
+ if (strcmp(task->name, "finalize_making_overhead") == 0)
+ need_exit = 1;
+
+ // XBT_INFO("exec");
+ // MSG_task_set_priority(task, 1000000);
+ MSG_task_execute(task);
+ MSG_task_destroy(task);
+
+ if (need_exit)
+ break;
+ }
+
+ // XBT_INFO("bye");
+
+ return 0;
+}
+
+static void start_overhead_process(msg_task_t comm_task)
+{
+ char *pr_name = bprintf("__pr_task_tx_overhead_%s", MSG_task_get_name(comm_task));
+ char *mbox = bprintf("__mb_task_tx_overhead_%s", MSG_task_get_name(comm_task));
+
+ int nargvs = 3;
+ char **argv = xbt_new(char *, nargvs);
+ argv[0] = pr_name;
+ argv[1] = mbox;
+ argv[2] = NULL;
+
+ // XBT_INFO("micro start: mbox %s", mbox);
+ MSG_process_create_with_arguments(pr_name, task_tx_overhead_fun, NULL, MSG_host_self(), nargvs - 1, argv);
+}
+
+static void shutdown_overhead_process(msg_task_t comm_task)
+{
+ char *mbox = bprintf("__mb_task_tx_overhead_%s", MSG_task_get_name(comm_task));
+
+ msg_task_t task = MSG_task_create("finalize_making_overhead", 0, 0, NULL);
+
+ // XBT_INFO("micro shutdown: mbox %s", mbox);
+ msg_error_t ret = MSG_task_send(task, mbox);
+ xbt_assert(ret == MSG_OK);
+
+ xbt_free(mbox);
+ // XBT_INFO("shutdown done");
+}
+
+static void request_overhead(msg_task_t comm_task, double computation)
+{
+ char *mbox = bprintf("__mb_task_tx_overhead_%s", MSG_task_get_name(comm_task));
+
+ msg_task_t task = MSG_task_create("micro", computation, 0, NULL);
+
+ // XBT_INFO("req overhead");
+ msg_error_t ret = MSG_task_send(task, mbox);
+ xbt_assert(ret == MSG_OK);
+
+ xbt_free(mbox);
+}
+
+/* alpha is (floating_operations / bytes).
+ *
+ * When actual migration traffic was 32 mbytes/s, we observed the CPU
+ * utilization of the main thread of the Qemu process was 10 %.
+ * alpha = 0.1 * C / (32 * 1024 * 1024)
+ * where the CPU capacity of the PM is C flops/s.
+ *
+ * */
+static void task_send_bounded_with_cpu_overhead(msg_task_t comm_task, char *mbox, double mig_speed, double alpha)
+{
+ const double chunk_size = 1024 * 1024 * 10;
+ double remaining = MSG_task_get_data_size(comm_task);
+
+ start_overhead_process(comm_task);
+
+
+ while (remaining > 0) {
+ double data_size = chunk_size;
+ if (remaining < chunk_size)
+ data_size = remaining;
+
+ remaining -= data_size;
+
+ // XBT_INFO("remaining %f bytes", remaining);
+
+
+ double clock_sta = MSG_get_clock();
+
+ /* create a micro task */
+ {
+ char *mtask_name = bprintf("__micro_%s", MSG_task_get_name(comm_task));
+ msg_task_t mtask = MSG_task_create(mtask_name, 0, data_size, NULL);
+
+ request_overhead(comm_task, data_size * alpha);
+
+ msg_error_t ret = MSG_task_send(mtask, mbox);
+ xbt_assert(ret == MSG_OK);
+
+ xbt_free(mtask_name);
+ }
+
+#if 0
+ {
+ /* In the real world, sending data involves small CPU computation. */
+ char *mtask_name = bprintf("__micro_%s", MSG_task_get_name(comm_task));
+ msg_task_t mtask = MSG_task_create(mtask_name, data_size * alpha, data_size, NULL);
+ MSG_task_execute(mtask);
+ MSG_task_destroy(mtask);
+ xbt_free(mtask_name);
+ }
+#endif
+
+ /* TODO */
+
+ double clock_end = MSG_get_clock();
+
+
+ if (mig_speed > 0) {
+ /*
+ * (max bandwidth) > data_size / ((elapsed time) + time_to_sleep)
+ *
+ * Thus, we get
+ * time_to_sleep > data_size / (max bandwidth) - (elapsed time)
+ *
+ * If time_to_sleep is smaller than zero, the elapsed time was too big. We
+ * do not need a micro sleep.
+ **/
+ double time_to_sleep = data_size / mig_speed - (clock_end - clock_sta);
+ if (time_to_sleep > 0)
+ MSG_process_sleep(time_to_sleep);
+
+
+ //XBT_INFO("duration %f", clock_end - clock_sta);
+ //XBT_INFO("time_to_sleep %f", time_to_sleep);
+ }
+ }
+
+ // XBT_INFO("%s", MSG_task_get_name(comm_task));
+ shutdown_overhead_process(comm_task);
+
+}
+
+
+#if 0
+static void make_cpu_overhead_of_data_transfer(msg_task_t comm_task, double init_comm_size)
+{
+ double prev_remaining = init_comm_size;
+
+ for (;;) {
+ double remaining = MSG_task_get_remaining_communication(comm_task);
+ if (remaining == 0)
+ need_exit = 1;
+
+ double sent = prev_remaining - remaining;
+ double comp_size = sent * overhead;
+
+
+ char *comp_task_name = bprintf("__sender_overhead%s", MSG_task_get_name(comm_task));
+ msg_task_t comp_task = MSG_task_create(comp_task_name, comp_size, 0, NULL);
+ MSG_task_execute(comp_task);
+ MSG_task_destroy(comp_task);
+
+ if (need_exit)
+ break;
+
+ prev_remaining = remaining;
+
+ }
+
+ xbt_free(comp_task_name);
+}
+#endif
+
+// #define USE_MICRO_TASK 1
+
+#if 0
+// const double alpha = 0.1L * 1.0E8 / (32L * 1024 * 1024);
+// const double alpha = 0.25L * 1.0E8 / (85L * 1024 * 1024);
+// const double alpha = 0.20L * 1.0E8 / (85L * 1024 * 1024);
+// const double alpha = 0.25L * 1.0E8 / (85L * 1024 * 1024);
+// const double alpha = 0.32L * 1.0E8 / (24L * 1024 * 1024); // makes super good values for 32 mbytes/s
+//const double alpha = 0.32L * 1.0E8 / (32L * 1024 * 1024);
+// const double alpha = 0.56L * 1.0E8 / (80L * 1024 * 1024);
+////const double alpha = 0.20L * 1.0E8 / (80L * 1024 * 1024);
+// const double alpha = 0.56L * 1.0E8 / (90L * 1024 * 1024);
+// const double alpha = 0.66L * 1.0E8 / (90L * 1024 * 1024);
+// const double alpha = 0.20L * 1.0E8 / (80L * 1024 * 1024);
+
+/* CPU 22% when 80Mbyte/s */
+const double alpha = 0.22L * 1.0E8 / (80L * 1024 * 1024);
+#endif
+
+
+static void send_migration_data(msg_vm_t vm, msg_host_t src_pm, msg_host_t dst_pm,
+ sg_size_t size, char *mbox, int stage, int stage2_round, double mig_speed, double xfer_cpu_overhead)
+{
+ char *task_name = get_mig_task_name(vm, src_pm, dst_pm, stage);
+ msg_task_t task = MSG_task_create(task_name, 0, size, NULL);
+
+ /* TODO: clean up */
+
+ double clock_sta = MSG_get_clock();
+
+#ifdef USE_MICRO_TASK
+
+ task_send_bounded_with_cpu_overhead(task, mbox, mig_speed, xfer_cpu_overhead);
+
+#else
+ msg_error_t ret;
+ if (mig_speed > 0)
+ ret = MSG_task_send_bounded(task, mbox, mig_speed);
+ else
+ ret = MSG_task_send(task, mbox);
+ xbt_assert(ret == MSG_OK);
+#endif
+
+ double clock_end = MSG_get_clock();
+ double duration = clock_end - clock_sta;
+ double actual_speed = size / duration;
+#ifdef USE_MICRO_TASK
+ double cpu_utilization = size * xfer_cpu_overhead / duration / 1.0E8;
+#else
+ double cpu_utilization = 0;
+#endif
+
+
+
+
+ if (stage == 2){
+ XBT_DEBUG("mig-stage%d.%d: sent %llu duration %f actual_speed %f (target %f) cpu %f", stage, stage2_round, size, duration, actual_speed, mig_speed, cpu_utilization);}
+ else{
+ XBT_DEBUG("mig-stage%d: sent %llu duration %f actual_speed %f (target %f) cpu %f", stage, size, duration, actual_speed, mig_speed, cpu_utilization);
+ }
+
+ xbt_free(task_name);
+
+
+
+#ifdef USE_MICRO_TASK
+ /* The name of a micro task starts with __micro, which does not match the
+ * special name that finalizes the receiver loop. Thus, we send the special task.
+ **/
+ {
+ if (stage == 3) {
+ char *task_name = get_mig_task_name(vm_name, src_pm_name, dst_pm_name, stage);
+ msg_task_t task = MSG_task_create(task_name, 0, 0, NULL);
+ msg_error_t ret = MSG_task_send(task, mbox);
+ xbt_assert(ret == MSG_OK);
+ xbt_free(task_name);
+ }
+ }
+#endif
+}
+
+static double get_updated_size(double computed, double dp_rate, double dp_cap)
+{
+ double updated_size = computed * dp_rate;
+ XBT_DEBUG("updated_size %f dp_rate %f", updated_size, dp_rate);
+ if (updated_size > dp_cap) {
+ // XBT_INFO("mig-stage2.%d: %f bytes updated, but cap it with the working set size %f", stage2_round, updated_size, dp_cap);
+ updated_size = dp_cap;
+ }
+
+ return updated_size;
+}
+
+static double send_stage1(struct migration_session *ms,
+ sg_size_t ramsize, double mig_speed, double xfer_cpu_overhead, double dp_rate, double dp_cap, double dpt_cpu_overhead)
+{
+
+ // const long chunksize = (sg_size_t)1024 * 1024 * 100;
+ const sg_size_t chunksize = (sg_size_t)1024 * 1024 * 100000;
+ sg_size_t remaining = ramsize;
+ double computed_total = 0;
+
+ while (remaining > 0) {
+ sg_size_t datasize = chunksize;
+ if (remaining < chunksize)
+ datasize = remaining;
+
+ remaining -= datasize;
+
+ send_migration_data(ms->vm, ms->src_pm, ms->dst_pm, datasize, ms->mbox, 1, 0, mig_speed, xfer_cpu_overhead);
+ double computed = lookup_computed_flop_counts(ms->vm, 1, 0);
+ computed_total += computed;
+
+ // {
+ // double updated_size = get_updated_size(computed, dp_rate, dp_cap);
+
+ // double overhead = dpt_cpu_overhead * updated_size;
+ // launch_deferred_exec_process(vm, overhead, 10000);
+ // }
+ }
+
+ return computed_total;
+}
+
+
+
+static double get_threshold_value(double bandwidth, double max_downtime)
+{
+ /* This value assumes the network link is 1Gbps. */
+ // double threshold = max_downtime * 125 * 1024 * 1024;
+ double threshold = max_downtime * bandwidth;
+
+ return threshold;
+}
+
+static int migration_tx_fun(int argc, char *argv[])
+{
+ XBT_DEBUG("mig: tx_start");
+
+ struct migration_session *ms = MSG_process_get_data(MSG_process_self());
+
+ s_ws_params_t params;
+ simcall_host_get_params(ms->vm, ¶ms);
+ const sg_size_t ramsize = params.ramsize;
+ const sg_size_t devsize = params.devsize;
+ const int skip_stage1 = params.skip_stage1;
+ const int skip_stage2 = params.skip_stage2;
+ const double dp_rate = params.dp_rate;
+ const double dp_cap = params.dp_cap;
+ const double mig_speed = params.mig_speed;
+ const double xfer_cpu_overhead = params.xfer_cpu_overhead;
+ const double dpt_cpu_overhead = params.dpt_cpu_overhead;
+
+ double remaining_size = ramsize + devsize;
+
+ double max_downtime = params.max_downtime;
+ if (max_downtime == 0) {
+ XBT_WARN("use the default max_downtime value 30ms");
+ max_downtime = 0.03;
+ }
+
+ double threshold = 0.00001; /* TODO: cleanup */
+
+ /* setting up parameters has done */
+
+
+ if (ramsize == 0)
+ XBT_WARN("migrate a VM, but ramsize is zero");
+
+
+ XBT_INFO("mig-stage1: remaining_size %f", remaining_size);
+
+ /* Stage1: send all memory pages to the destination. */
+ start_dirty_page_tracking(ms->vm);
+
+ double computed_during_stage1 = 0;
+ if (!skip_stage1) {
+ // send_migration_data(vm_name, src_pm_name, dst_pm_name, ramsize, mbox, 1, 0, mig_speed, xfer_cpu_overhead);
+
+ /* send ramsize, but split it */
+ double clock_prev_send = MSG_get_clock();
+
+ computed_during_stage1 = send_stage1(ms, ramsize, mig_speed, xfer_cpu_overhead, dp_rate, dp_cap, dpt_cpu_overhead);
+ remaining_size -= ramsize;
+
+ double clock_post_send = MSG_get_clock();
+ double bandwidth = ramsize / (clock_post_send - clock_prev_send);
+ threshold = get_threshold_value(bandwidth, max_downtime);
+ XBT_INFO("actual bandwidth %f (MB/s), threshold %f", bandwidth / 1024 / 1024, threshold);
+ }
+
+
+ /* Stage2: send update pages iteratively until the size of remaining states
+ * becomes smaller than the threshold value. */
+ if (skip_stage2)
+ goto stage3;
+ if (max_downtime == 0) {
+ XBT_WARN("no max_downtime parameter, skip stage2");
+ goto stage3;
+ }
+
+
+ int stage2_round = 0;
+ for (;;) {
+
+ double updated_size = 0;
+ if (stage2_round == 0) {
+ /* just after stage1, nothing has been updated. But, we have to send the data updated during stage1 */
+ updated_size = get_updated_size(computed_during_stage1, dp_rate, dp_cap);
+ } else {
+ double computed = lookup_computed_flop_counts(ms->vm, 2, stage2_round);
+ updated_size = get_updated_size(computed, dp_rate, dp_cap);
+ }
+
+ XBT_INFO("mig-stage 2:%d updated_size %f computed_during_stage1 %f dp_rate %f dp_cap %f",
+ stage2_round, updated_size, computed_during_stage1, dp_rate, dp_cap);
+
+
+ // if (stage2_round != 0) {
+ // /* during stage1, we have already created overhead tasks */
+ // double overhead = dpt_cpu_overhead * updated_size;
+ // XBT_DEBUG("updated %f overhead %f", updated_size, overhead);
+ // launch_deferred_exec_process(vm, overhead, 10000);
+ // }
+
+
+ {
+ remaining_size += updated_size;
+
+ XBT_INFO("mig-stage2.%d: remaining_size %f (%s threshold %f)", stage2_round,
+ remaining_size, (remaining_size < threshold) ? "<" : ">", threshold);
+
+ if (remaining_size < threshold)
+ break;
+ }
+
+ double clock_prev_send = MSG_get_clock();
+
+ send_migration_data(ms->vm, ms->src_pm, ms->dst_pm, updated_size, ms->mbox, 2, stage2_round, mig_speed, xfer_cpu_overhead);
+
+ double clock_post_send = MSG_get_clock();
+
+ double bandwidth = updated_size / (clock_post_send - clock_prev_send);
+ threshold = get_threshold_value(bandwidth, max_downtime);
+ XBT_INFO("actual bandwidth %f, threshold %f", bandwidth / 1024 / 1024, threshold);
+
+
+ remaining_size -= updated_size;
+ stage2_round += 1;
+ }
+
+
+stage3:
+ /* Stage3: stop the VM and copy the rest of states. */
+ XBT_INFO("mig-stage3: remaining_size %f", remaining_size);
+ simcall_vm_suspend(ms->vm);
+ stop_dirty_page_tracking(ms->vm);
+
+ send_migration_data(ms->vm, ms->src_pm, ms->dst_pm, remaining_size, ms->mbox, 3, 0, mig_speed, xfer_cpu_overhead);
+
+
+ XBT_DEBUG("mig: tx_done");
+
+ return 0;
+}
+
+
+
+static void do_migration(msg_vm_t vm, msg_host_t src_pm, msg_host_t dst_pm)
+{
+ struct migration_session *ms = xbt_new(struct migration_session, 1);
+ ms->vm = vm;
+ ms->src_pm = src_pm;
+ ms->dst_pm = dst_pm;
+ ms->mbox_ctl = get_mig_mbox_ctl(vm, src_pm, dst_pm);
+ ms->mbox = get_mig_mbox_src_dst(vm, src_pm, dst_pm);
+
+ char *pr_rx_name = get_mig_process_rx_name(vm, src_pm, dst_pm);
+ char *pr_tx_name = get_mig_process_tx_name(vm, src_pm, dst_pm);
+
+// MSG_process_create(pr_rx_name, migration_rx_fun, ms, dst_pm);
+// MSG_process_create(pr_tx_name, migration_tx_fun, ms, src_pm);
+#if 1
+ {
+ char **argv = xbt_new(char *, 2);
+ argv[0] = pr_rx_name;
+ argv[1] = NULL;
+ MSG_process_create_with_arguments(pr_rx_name, migration_rx_fun, ms, dst_pm, 1, argv);
+ }
+ {
+ char **argv = xbt_new(char *, 2);
+ argv[0] = pr_tx_name;
+ argv[1] = NULL;
+ MSG_process_create_with_arguments(pr_tx_name, migration_tx_fun, ms, src_pm, 1, argv);
+ }
+#endif
+
+
+
+
+ /* wait until the migration have finished */
+ {
+ msg_task_t task = NULL;
+ msg_error_t ret = MSG_task_recv(&task, ms->mbox_ctl);
+
+ xbt_assert(ret == MSG_OK);
+
+ char *expected_task_name = get_mig_task_name(vm, src_pm, dst_pm, 4);
+ xbt_assert(strcmp(task->name, expected_task_name) == 0);
+ xbt_free(expected_task_name);
+ MSG_task_destroy(task);
+ }
+
+ xbt_free(ms->mbox_ctl);
+ xbt_free(ms->mbox);
+ xbt_free(ms);
+}
+
+
+/** @brief Migrate the VM to the given host.
+ * @ingroup msg_VMs
+ *
+ * FIXME: No migration cost occurs. If you want to simulate this too, you want to use a
+ * MSG_task_send() before or after, depending on whether you want to do cold or hot
+ * migration.
+ */
+void MSG_vm_migrate(msg_vm_t vm, msg_host_t new_pm)
+{
+ /* some thoughts:
+ * - One approach is ...
+ * We first create a new VM (i.e., destination VM) on the destination
+ * physical host. The destination VM will receive the state of the source
+ * VM over network. We will finally destroy the source VM.
+ * - This behavior is similar to the way of migration in the real world.
+ * Even before a migration is completed, we will see a destination VM,
+ * consuming resources.
+ * - We have to relocate all processes. The existing process migraion code
+ * will work for this?
+ * - The name of the VM is a somewhat unique ID in the code. It is tricky
+ * for the destination VM?
+ *
+ * - Another one is ...
+ * We update the information of the given VM to place it to the destination
+ * physical host.
+ *
+ * The second one would be easier.
+ *
+ */
+
+ msg_host_t old_pm = simcall_vm_get_pm(vm);
+
+ if (!MSG_vm_is_running(vm))
+ THROWF(vm_error, 0, "VM(%s) is not running", sg_host_name(vm));
+
+ if (MSG_vm_is_migrating(vm))
+ THROWF(vm_error, 0, "VM(%s) is already migrating", sg_host_name(vm));
+
+ msg_host_priv_t priv = msg_host_resource_priv(vm);
+ priv->is_migrating = 1;
+
+ do_migration(vm, old_pm, new_pm);
+
+ priv->is_migrating = 0;
+
+ XBT_DEBUG("VM(%s) moved from PM(%s) to PM(%s)", vm->key, old_pm->key, new_pm->key);
+