1 /* Copyright (c) 2012-2015. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
8 * 1. add the support of trace
9 * 2. use parallel tasks to simulate CPU overhead and remove the experimental code generating micro computation tasks
14 #include "src/instr/instr_private.h"
15 #include "src/msg/msg_private.h"
16 #include "src/plugins/vm/VirtualMachineImpl.hpp"
17 #include "src/plugins/vm/VmHostExt.hpp"
19 #include "simgrid/host.h"
20 #include "simgrid/simix.hpp"
26 double prev_remaining;
29 typedef struct dirty_page s_dirty_page;
30 typedef struct dirty_page* dirty_page_t;
32 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(msg_vm, msg, "Cloud-oriented parts of the MSG API");
34 /* **** ******** GENERAL ********* **** */
36 /** \ingroup m_vm_management
37 * \brief Set the parameters of a given host
40 * \param params a parameter object
42 void MSG_vm_set_params(msg_vm_t vm, vm_params_t params)
44 static_cast<simgrid::s4u::VirtualMachine*>(vm)->setParameters(params);
47 /** \ingroup m_vm_management
48 * \brief Get the parameters of a given host
50 * \param vm the vm you are interested into
51 * \param params a prameter object
53 void MSG_vm_get_params(msg_vm_t vm, vm_params_t params)
55 static_cast<simgrid::s4u::VirtualMachine*>(vm)->parameters(params);
58 /* **** Check state of a VM **** */
59 static inline int __MSG_vm_is_state(msg_vm_t vm, e_surf_vm_state_t state)
61 simgrid::s4u::VirtualMachine* castedVm = static_cast<simgrid::s4u::VirtualMachine*>(vm);
62 return castedVm->pimpl_vm_ != nullptr && castedVm->pimpl_vm_->getState() == state;
65 /** @brief Returns whether the given VM has just created, not running.
68 int MSG_vm_is_created(msg_vm_t vm)
70 return __MSG_vm_is_state(vm, SURF_VM_STATE_CREATED);
73 /** @brief Returns whether the given VM is currently running
76 int MSG_vm_is_running(msg_vm_t vm)
78 return __MSG_vm_is_state(vm, SURF_VM_STATE_RUNNING);
81 /** @brief Returns whether the given VM is currently migrating
84 int MSG_vm_is_migrating(msg_vm_t vm)
86 return static_cast<simgrid::s4u::VirtualMachine*>(vm)->isMigrating();
89 /** @brief Returns whether the given VM is currently suspended, not running.
92 int MSG_vm_is_suspended(msg_vm_t vm)
94 return __MSG_vm_is_state(vm, SURF_VM_STATE_SUSPENDED);
97 /* **** ******** MSG vm actions ********* **** */
98 /** @brief Create a new VM with specified parameters.
100 * @param pm Physical machine that will host the VM
101 * @param name Must be unique
102 * @param ramsize [TODO]
103 * @param mig_netspeed Amount of Mbyte/s allocated to the migration (cannot be larger than net_cap). Use 0 if unsure.
104 * @param dp_intensity Dirty page percentage according to migNetSpeed, [0-100]. Use 0 if unsure.
106 msg_vm_t MSG_vm_create(msg_host_t pm, const char* name, int ramsize, int mig_netspeed, int dp_intensity)
108 simgrid::vm::VmHostExt::ensureVmExtInstalled();
110 /* For the moment, intensity_rate is the percentage against the migration bandwidth */
111 double host_speed = MSG_host_get_speed(pm);
112 double update_speed = (static_cast<double>(dp_intensity)/100) * mig_netspeed;
114 msg_vm_t vm = MSG_vm_create_core(pm, name);
115 s_vm_params_t params;
116 memset(¶ms, 0, sizeof(params));
117 params.ramsize = static_cast<sg_size_t>(ramsize) * 1024 * 1024;
119 params.skip_stage2 = 0;
120 params.max_downtime = 0.03;
121 params.dp_rate = (update_speed * 1024 * 1024) / host_speed;
122 params.dp_cap = params.ramsize * 0.9; // assume working set memory is 90% of ramsize
123 params.mig_speed = static_cast<double>(mig_netspeed) * 1024 * 1024; // mig_speed
125 XBT_DEBUG("dp rate %f migspeed : %f intensity mem : %d, updatespeed %f, hostspeed %f", params.dp_rate,
126 params.mig_speed, dp_intensity, update_speed, host_speed);
127 static_cast<simgrid::s4u::VirtualMachine*>(vm)->setParameters(¶ms);
132 /** @brief Create a new VM object. The VM is not yet started. The resource of the VM is allocated upon MSG_vm_start().
135 * A VM is treated as a host. The name of the VM must be unique among all hosts.
137 msg_vm_t MSG_vm_create_core(msg_host_t pm, const char* name)
139 xbt_assert(sg_host_by_name(name) == nullptr,
140 "Cannot create a VM named %s: this name is already used by an host or a VM", name);
142 return new simgrid::s4u::VirtualMachine(name, pm);
145 /** @brief Destroy a VM. Destroy the VM object from the simulation.
148 void MSG_vm_destroy(msg_vm_t vm)
150 if (MSG_vm_is_migrating(vm))
151 THROWF(vm_error, 0, "Cannot destroy VM '%s', which is migrating.", vm->cname());
153 /* First, terminate all processes on the VM if necessary */
154 if (MSG_vm_is_running(vm))
157 xbt_assert(MSG_vm_is_created(vm) || __MSG_vm_is_state(vm, SURF_VM_STATE_DESTROYED),
158 "shutdown the given VM before destroying it");
160 /* Then, destroy the VM object */
161 simgrid::simix::kernelImmediate([vm]() {
165 if (TRACE_msg_vm_is_enabled()) {
166 container_t container = PJ_container_get(vm->cname());
167 PJ_container_remove_from_parent(container);
168 PJ_container_free(container);
172 /** @brief Start a vm (i.e., boot the guest operating system)
175 * If the VM cannot be started (because of memory overprovisionning), an exception is generated.
177 void MSG_vm_start(msg_vm_t vm)
179 simgrid::simix::kernelImmediate([vm]() {
180 simgrid::vm::VmHostExt::ensureVmExtInstalled();
182 simgrid::s4u::VirtualMachine* typedVM = static_cast<simgrid::s4u::VirtualMachine*>(vm);
183 simgrid::s4u::Host* pm = typedVM->pimpl_vm_->getPm();
184 if (pm->extension<simgrid::vm::VmHostExt>() == nullptr)
185 pm->extension_set(new simgrid::vm::VmHostExt());
187 long pm_ramsize = pm->extension<simgrid::vm::VmHostExt>()->ramsize;
188 int pm_overcommit = pm->extension<simgrid::vm::VmHostExt>()->overcommit;
189 long vm_ramsize = typedVM->getRamsize();
191 if (pm_ramsize && not pm_overcommit) { /* Only verify that we don't overcommit on need */
192 /* Retrieve the memory occupied by the VMs on that host. Yep, we have to traverse all VMs of all hosts for that */
193 long total_ramsize_of_vms = 0;
194 for (simgrid::s4u::VirtualMachine* ws_vm : simgrid::vm::VirtualMachineImpl::allVms_)
195 if (pm == ws_vm->pimpl_vm_->getPm())
196 total_ramsize_of_vms += ws_vm->pimpl_vm_->getRamsize();
198 if (vm_ramsize > pm_ramsize - total_ramsize_of_vms) {
199 XBT_WARN("cannnot start %s@%s due to memory shortage: vm_ramsize %ld, free %ld, pm_ramsize %ld (bytes).",
200 vm->cname(), pm->cname(), vm_ramsize, pm_ramsize - total_ramsize_of_vms, pm_ramsize);
201 THROWF(vm_error, 0, "Memory shortage on host '%s', VM '%s' cannot be started", pm->cname(), vm->cname());
205 typedVM->pimpl_vm_->setState(SURF_VM_STATE_RUNNING);
208 if (TRACE_msg_vm_is_enabled()) {
209 container_t vm_container = PJ_container_get(vm->cname());
210 type_t type = PJ_type_get("MSG_VM_STATE", vm_container->type);
211 val_t value = PJ_value_get_or_new("start", "0 0 1", type); // start is blue
212 new PushStateEvent(MSG_get_clock(), vm_container, type, value);
216 /** @brief Immediately kills all processes within the given VM.
219 * Any memory that they allocated will be leaked, unless you used #MSG_process_on_exit().
221 * No extra delay occurs. If you want to simulate this too, you want to use a #MSG_process_sleep().
223 void MSG_vm_shutdown(msg_vm_t vm)
225 smx_actor_t issuer=SIMIX_process_self();
226 simgrid::simix::kernelImmediate([vm,issuer]() {
227 static_cast<simgrid::s4u::VirtualMachine*>(vm)->pimpl_vm_->shutdown(issuer);
230 // Make sure that the processes in the VM are killed in this scheduling round before processing
231 // (eg with the VM destroy)
232 MSG_process_sleep(0.);
235 static inline char *get_mig_process_tx_name(msg_vm_t vm, msg_host_t src_pm, msg_host_t dst_pm)
237 return bprintf("__pr_mig_tx:%s(%s-%s)", vm->cname(), src_pm->cname(), dst_pm->cname());
240 static inline char *get_mig_process_rx_name(msg_vm_t vm, msg_host_t src_pm, msg_host_t dst_pm)
242 return bprintf("__pr_mig_rx:%s(%s-%s)", vm->cname(), src_pm->cname(), dst_pm->cname());
245 static inline char *get_mig_task_name(msg_vm_t vm, msg_host_t src_pm, msg_host_t dst_pm, int stage)
247 return bprintf("__task_mig_stage%d:%s(%s-%s)", stage, vm->cname(), src_pm->cname(), dst_pm->cname());
250 struct migration_session {
255 /* The miration_rx process uses mbox_ctl to let the caller of do_migration()
256 * know the completion of the migration. */
258 /* The migration_rx and migration_tx processes use mbox to transfer migration data. */
262 static int migration_rx_fun(int argc, char *argv[])
264 XBT_DEBUG("mig: rx_start");
266 // The structure has been created in the do_migration function and should only be freed in the same place ;)
267 struct migration_session *ms = (migration_session *) MSG_process_get_data(MSG_process_self());
269 bool received_finalize = false;
271 char *finalize_task_name = get_mig_task_name(ms->vm, ms->src_pm, ms->dst_pm, 3);
272 while (not received_finalize) {
273 msg_task_t task = nullptr;
274 int ret = MSG_task_recv(&task, ms->mbox);
277 // An error occurred, clean the code and return
278 // The owner did not change, hence the task should be only destroyed on the other side
279 xbt_free(finalize_task_name);
283 if (strcmp(task->name, finalize_task_name) == 0)
284 received_finalize = 1;
286 MSG_task_destroy(task);
288 xbt_free(finalize_task_name);
290 // Here Stage 1, 2 and 3 have been performed.
291 // Hence complete the migration
293 // Copy the reference to the vm (if SRC crashes now, do_migration will free ms)
294 // This is clearly ugly but I (Adrien) need more time to do something cleaner (actually we should copy the whole ms
295 // structure at the beginning and free it at the end of each function)
296 simgrid::s4u::VirtualMachine* vm = static_cast<simgrid::s4u::VirtualMachine*>(ms->vm);
297 msg_host_t dst_pm = ms->dst_pm;
299 // Make sure that we cannot get interrupted between the migrate and the resume to not end in an inconsistent state
300 simgrid::simix::kernelImmediate([vm, dst_pm]() {
301 /* Update the vm location */
302 /* precopy migration makes the VM temporally paused */
303 xbt_assert(vm->pimpl_vm_->getState() == SURF_VM_STATE_SUSPENDED);
305 /* Update the vm location and resume it */
306 vm->pimpl_vm_->setPm(dst_pm);
307 vm->pimpl_vm_->resume();
311 // Now the VM is running on the new host (the migration is completed) (even if the SRC crash)
312 vm->pimpl_vm_->isMigrating = false;
313 XBT_DEBUG("VM(%s) moved from PM(%s) to PM(%s)", ms->vm->cname(), ms->src_pm->cname(), ms->dst_pm->cname());
315 if (TRACE_msg_vm_is_enabled()) {
316 static long long int counter = 0;
317 char key[INSTR_DEFAULT_STR_SIZE];
318 snprintf(key, INSTR_DEFAULT_STR_SIZE, "%lld", counter);
322 container_t msg = PJ_container_get(vm->cname());
323 type_t type = PJ_type_get("MSG_VM_LINK", PJ_type_get_root());
324 new StartLinkEvent(MSG_get_clock(), PJ_container_get_root(), type, msg, "M", key);
326 // destroy existing container of this vm
327 container_t existing_container = PJ_container_get(vm->cname());
328 PJ_container_remove_from_parent(existing_container);
329 PJ_container_free(existing_container);
331 // create new container on the new_host location
332 PJ_container_new(vm->cname(), INSTR_MSG_VM, PJ_container_get(ms->dst_pm->cname()));
335 msg = PJ_container_get(vm->cname());
336 type = PJ_type_get("MSG_VM_LINK", PJ_type_get_root());
337 new EndLinkEvent(MSG_get_clock(), PJ_container_get_root(), type, msg, "M", key);
340 // Inform the SRC that the migration has been correctly performed
341 char *task_name = get_mig_task_name(ms->vm, ms->src_pm, ms->dst_pm, 4);
342 msg_task_t task = MSG_task_create(task_name, 0, 0, nullptr);
343 msg_error_t ret = MSG_task_send(task, ms->mbox_ctl);
344 // xbt_assert(ret == MSG_OK);
345 if(ret == MSG_HOST_FAILURE){
346 // The DST has crashed, this is a problem has the VM since we are not sure whether SRC is considering that the VM
347 // has been correctly migrated on the DST node
348 // TODO What does it mean ? What should we do ?
349 MSG_task_destroy(task);
350 } else if(ret == MSG_TRANSFER_FAILURE){
351 // The SRC has crashed, this is not a problem has the VM has been correctly migrated on the DST node
352 MSG_task_destroy(task);
356 XBT_DEBUG("mig: rx_done");
360 static void start_dirty_page_tracking(msg_vm_t vm)
362 simgrid::vm::VirtualMachineImpl* pimpl = static_cast<simgrid::s4u::VirtualMachine*>(vm)->pimpl_vm_;
364 pimpl->dp_enabled = 1;
365 if (not pimpl->dp_objs)
369 xbt_dict_cursor_t cursor = nullptr;
370 dirty_page_t dp = nullptr;
371 xbt_dict_foreach (pimpl->dp_objs, cursor, key, dp) {
372 double remaining = MSG_task_get_flops_amount(dp->task);
373 dp->prev_clock = MSG_get_clock();
374 dp->prev_remaining = remaining;
376 // XBT_INFO("%s@%s remaining %f", key, sg_host_name(vm), remaining);
380 static void stop_dirty_page_tracking(msg_vm_t vm)
382 static_cast<simgrid::s4u::VirtualMachine*>(vm)->pimpl_vm_->dp_enabled = 0;
385 static double get_computed(char *key, msg_vm_t vm, dirty_page_t dp, double remaining, double clock)
387 double computed = dp->prev_remaining - remaining;
388 double duration = clock - dp->prev_clock;
390 XBT_DEBUG("%s@%s: computed %f ops (remaining %f -> %f) in %f secs (%f -> %f)", key, vm->cname(), computed,
391 dp->prev_remaining, remaining, duration, dp->prev_clock, clock);
396 static double lookup_computed_flop_counts(msg_vm_t vm, int stage_for_fancy_debug, int stage2_round_for_fancy_debug)
398 simgrid::vm::VirtualMachineImpl* pimpl = static_cast<simgrid::s4u::VirtualMachine*>(vm)->pimpl_vm_;
402 xbt_dict_cursor_t cursor = nullptr;
403 dirty_page_t dp = nullptr;
404 xbt_dict_foreach (pimpl->dp_objs, cursor, key, dp) {
405 double remaining = MSG_task_get_flops_amount(dp->task);
407 double clock = MSG_get_clock();
409 // total += calc_updated_pages(key, vm, dp, remaining, clock);
410 total += get_computed(key, vm, dp, remaining, clock);
412 dp->prev_remaining = remaining;
413 dp->prev_clock = clock;
416 total += pimpl->dp_updated_by_deleted_tasks;
418 XBT_DEBUG("mig-stage%d.%d: computed %f flop_counts (including %f by deleted tasks)", stage_for_fancy_debug,
419 stage2_round_for_fancy_debug, total, pimpl->dp_updated_by_deleted_tasks);
421 pimpl->dp_updated_by_deleted_tasks = 0;
426 // TODO Is this code redundant with the information provided by
427 // msg_process_t MSG_process_create(const char *name, xbt_main_func_t code, void *data, msg_host_t host)
428 /** @brief take care of the dirty page tracking, in case we're adding a task to a migrating VM */
429 void MSG_host_add_task(msg_host_t host, msg_task_t task)
431 simgrid::s4u::VirtualMachine* vm = dynamic_cast<simgrid::s4u::VirtualMachine*>(host);
434 simgrid::vm::VirtualMachineImpl* pimpl = static_cast<simgrid::s4u::VirtualMachine*>(vm)->pimpl_vm_;
436 double remaining = MSG_task_get_flops_amount(task);
437 char *key = bprintf("%s-%p", task->name, task);
439 dirty_page_t dp = xbt_new0(s_dirty_page, 1);
441 if (pimpl->dp_enabled) {
442 dp->prev_clock = MSG_get_clock();
443 dp->prev_remaining = remaining;
445 if (not pimpl->dp_objs)
446 pimpl->dp_objs = xbt_dict_new_homogeneous(nullptr);
447 xbt_assert(xbt_dict_get_or_null(pimpl->dp_objs, key) == nullptr);
448 xbt_dict_set(pimpl->dp_objs, key, dp, nullptr);
449 XBT_DEBUG("add %s on %s (remaining %f, dp_enabled %d)", key, host->cname(), remaining, pimpl->dp_enabled);
454 void MSG_host_del_task(msg_host_t host, msg_task_t task)
456 simgrid::s4u::VirtualMachine* vm = dynamic_cast<simgrid::s4u::VirtualMachine*>(host);
459 simgrid::vm::VirtualMachineImpl* pimpl = static_cast<simgrid::s4u::VirtualMachine*>(vm)->pimpl_vm_;
461 char *key = bprintf("%s-%p", task->name, task);
462 dirty_page_t dp = (dirty_page_t)(pimpl->dp_objs ? xbt_dict_get_or_null(pimpl->dp_objs, key) : NULL);
463 xbt_assert(dp->task == task);
465 /* If we are in the middle of dirty page tracking, we record how much computation has been done until now, and keep
466 * the information for the lookup_() function that will called soon. */
467 if (pimpl->dp_enabled) {
468 double remaining = MSG_task_get_flops_amount(task);
469 double clock = MSG_get_clock();
470 // double updated = calc_updated_pages(key, host, dp, remaining, clock);
471 double updated = get_computed(key, host, dp, remaining, clock);
473 pimpl->dp_updated_by_deleted_tasks += updated;
476 xbt_dict_remove(pimpl->dp_objs, key);
479 XBT_DEBUG("del %s on %s", key, host->cname());
483 static sg_size_t send_migration_data(msg_vm_t vm, msg_host_t src_pm, msg_host_t dst_pm, sg_size_t size, char* mbox,
484 int stage, int stage2_round, double mig_speed, double timeout)
487 char *task_name = get_mig_task_name(vm, src_pm, dst_pm, stage);
488 msg_task_t task = MSG_task_create(task_name, 0, static_cast<double>(size), nullptr);
492 double clock_sta = MSG_get_clock();
496 ret = MSG_task_send_with_timeout_bounded(task, mbox, timeout, mig_speed);
498 ret = MSG_task_send(task, mbox);
504 } else if (ret == MSG_TIMEOUT) {
505 sg_size_t remaining = static_cast<sg_size_t>(MSG_task_get_remaining_communication(task));
506 sent = size - remaining;
507 XBT_VERB("timeout (%lf s) in sending_migration_data, remaining %llu bytes of %llu", timeout, remaining, size);
510 /* FIXME: why try-and-catch is used here? */
511 if(ret == MSG_HOST_FAILURE){
512 XBT_DEBUG("SRC host failed during migration of %s (stage %d)", vm->cname(), stage);
513 MSG_task_destroy(task);
514 THROWF(host_error, 0, "SRC host failed during migration of %s (stage %d)", vm->cname(), stage);
515 }else if(ret == MSG_TRANSFER_FAILURE){
516 XBT_DEBUG("DST host failed during migration of %s (stage %d)", vm->cname(), stage);
517 MSG_task_destroy(task);
518 THROWF(host_error, 0, "DST host failed during migration of %s (stage %d)", vm->cname(), stage);
521 double clock_end = MSG_get_clock();
522 double duration = clock_end - clock_sta;
523 double actual_speed = size / duration;
526 XBT_DEBUG("mig-stage%d.%d: sent %llu duration %f actual_speed %f (target %f)", stage, stage2_round, size, duration,
527 actual_speed, mig_speed);
529 XBT_DEBUG("mig-stage%d: sent %llu duration %f actual_speed %f (target %f)", stage, size, duration, actual_speed,
535 static sg_size_t get_updated_size(double computed, double dp_rate, double dp_cap)
537 double updated_size = computed * dp_rate;
538 XBT_DEBUG("updated_size %f dp_rate %f", updated_size, dp_rate);
539 if (updated_size > dp_cap) {
540 // XBT_INFO("mig-stage2.%d: %f bytes updated, but cap it with the working set size %f", stage2_round, updated_size,
542 updated_size = dp_cap;
545 return static_cast<sg_size_t>(updated_size);
548 static int migration_tx_fun(int argc, char *argv[])
550 XBT_DEBUG("mig: tx_start");
552 // Note that the ms structure has been allocated in do_migration and hence should be freed in the same function ;)
553 migration_session *ms = static_cast<migration_session *>(MSG_process_get_data(MSG_process_self()));
555 s_vm_params_t params;
556 static_cast<simgrid::s4u::VirtualMachine*>(ms->vm)->parameters(¶ms);
557 const sg_size_t ramsize = params.ramsize;
558 const sg_size_t devsize = params.devsize;
559 const int skip_stage1 = params.skip_stage1;
560 int skip_stage2 = params.skip_stage2;
561 const double dp_rate = params.dp_rate;
562 const double dp_cap = params.dp_cap;
563 const double mig_speed = params.mig_speed;
564 double max_downtime = params.max_downtime;
566 double mig_timeout = 10000000.0;
568 double remaining_size = static_cast<double>(ramsize + devsize);
569 double threshold = 0.0;
571 /* check parameters */
573 XBT_WARN("migrate a VM, but ramsize is zero");
575 if (max_downtime <= 0) {
576 XBT_WARN("use the default max_downtime value 30ms");
580 /* Stage1: send all memory pages to the destination. */
581 XBT_DEBUG("mig-stage1: remaining_size %f", remaining_size);
582 start_dirty_page_tracking(ms->vm);
584 double computed_during_stage1 = 0;
585 if (not skip_stage1) {
586 double clock_prev_send = MSG_get_clock();
589 /* At stage 1, we do not need timeout. We have to send all the memory pages even though the duration of this
590 * transfer exceeds the timeout value. */
591 XBT_VERB("Stage 1: Gonna send %llu", ramsize);
592 sg_size_t sent = send_migration_data(ms->vm, ms->src_pm, ms->dst_pm, ramsize, ms->mbox, 1, 0, mig_speed, -1);
593 remaining_size -= sent;
594 computed_during_stage1 = lookup_computed_flop_counts(ms->vm, 1, 0);
596 if (sent < ramsize) {
597 XBT_VERB("mig-stage1: timeout, force moving to stage 3");
599 } else if (sent > ramsize)
604 //hostfailure (if you want to know whether this is the SRC or the DST check directly in send_migration_data code)
605 // Stop the dirty page tracking an return (there is no memory space to release)
606 stop_dirty_page_tracking(ms->vm);
610 double clock_post_send = MSG_get_clock();
611 mig_timeout -= (clock_post_send - clock_prev_send);
612 if (mig_timeout < 0) {
613 XBT_VERB("The duration of stage 1 exceeds the timeout value, skip stage 2");
617 /* estimate bandwidth */
618 double bandwidth = ramsize / (clock_post_send - clock_prev_send);
619 threshold = bandwidth * max_downtime;
620 XBT_DEBUG("actual bandwidth %f (MB/s), threshold %f", bandwidth / 1024 / 1024, threshold);
624 /* Stage2: send update pages iteratively until the size of remaining states becomes smaller than threshold value. */
625 if (not skip_stage2) {
627 int stage2_round = 0;
630 sg_size_t updated_size = 0;
631 if (stage2_round == 0) {
632 /* just after stage1, nothing has been updated. But, we have to send the data updated during stage1 */
633 updated_size = get_updated_size(computed_during_stage1, dp_rate, dp_cap);
635 double computed = lookup_computed_flop_counts(ms->vm, 2, stage2_round);
636 updated_size = get_updated_size(computed, dp_rate, dp_cap);
639 XBT_DEBUG("mig-stage 2:%d updated_size %llu computed_during_stage1 %f dp_rate %f dp_cap %f", stage2_round,
640 updated_size, computed_during_stage1, dp_rate, dp_cap);
642 /* Check whether the remaining size is below the threshold value. If so, move to stage 3. */
643 remaining_size += updated_size;
644 XBT_DEBUG("mig-stage2.%d: remaining_size %f (%s threshold %f)", stage2_round, remaining_size,
645 (remaining_size < threshold) ? "<" : ">", threshold);
646 if (remaining_size < threshold)
650 double clock_prev_send = MSG_get_clock();
652 XBT_DEBUG("Stage 2, gonna send %llu", updated_size);
653 sent = send_migration_data(ms->vm, ms->src_pm, ms->dst_pm, updated_size, ms->mbox, 2, stage2_round, mig_speed,
655 } catch (xbt_ex& e) {
656 // hostfailure (if you want to know whether this is the SRC or the DST check directly in send_migration_data
658 // Stop the dirty page tracking an return (there is no memory space to release)
659 stop_dirty_page_tracking(ms->vm);
662 double clock_post_send = MSG_get_clock();
664 if (sent == updated_size) {
665 /* timeout did not happen */
666 double bandwidth = updated_size / (clock_post_send - clock_prev_send);
667 threshold = bandwidth * max_downtime;
668 XBT_DEBUG("actual bandwidth %f, threshold %f", bandwidth / 1024 / 1024, threshold);
669 remaining_size -= sent;
671 mig_timeout -= (clock_post_send - clock_prev_send);
672 xbt_assert(mig_timeout > 0);
674 } else if (sent < updated_size) {
675 /* When timeout happens, we move to stage 3. The size of memory pages
676 * updated before timeout must be added to the remaining size. */
677 XBT_VERB("mig-stage2.%d: timeout, force moving to stage 3. sent %llu / %llu, eta %lf", stage2_round, sent,
678 updated_size, (clock_post_send - clock_prev_send));
679 remaining_size -= sent;
681 double computed = lookup_computed_flop_counts(ms->vm, 2, stage2_round);
682 updated_size = get_updated_size(computed, dp_rate, dp_cap);
683 remaining_size += updated_size;
690 /* Stage3: stop the VM and copy the rest of states. */
691 XBT_DEBUG("mig-stage3: remaining_size %f", remaining_size);
692 simgrid::vm::VirtualMachineImpl* pimpl = static_cast<simgrid::s4u::VirtualMachine*>(ms->vm)->pimpl_vm_;
693 pimpl->setState(SURF_VM_STATE_RUNNING); // FIXME: this bypass of the checks in suspend() is not nice
694 pimpl->isMigrating = false; // FIXME: this bypass of the checks in suspend() is not nice
695 pimpl->suspend(SIMIX_process_self());
696 stop_dirty_page_tracking(ms->vm);
699 XBT_DEBUG("Stage 3: Gonna send %f", remaining_size);
700 send_migration_data(ms->vm, ms->src_pm, ms->dst_pm, static_cast<sg_size_t>(remaining_size), ms->mbox, 3, 0,
704 //hostfailure (if you want to know whether this is the SRC or the DST check directly in send_migration_data code)
705 // Stop the dirty page tracking an return (there is no memory space to release)
706 static_cast<simgrid::s4u::VirtualMachine*>(ms->vm)->pimpl_vm_->resume();
710 // At that point the Migration is considered valid for the SRC node but remind that the DST side should relocate
711 // effectively the VM on the DST node.
712 XBT_DEBUG("mig: tx_done");
717 /** @brief Migrate the VM to the given host.
720 void MSG_vm_migrate(msg_vm_t vm, msg_host_t dst_pm)
723 * - One approach is ...
724 * We first create a new VM (i.e., destination VM) on the destination physical host. The destination VM will
725 * receive the state of the source
726 * VM over network. We will finally destroy the source VM.
727 * - This behavior is similar to the way of migration in the real world.
728 * Even before a migration is completed, we will see a destination VM, consuming resources.
729 * - We have to relocate all processes. The existing process migration code will work for this?
730 * - The name of the VM is a somewhat unique ID in the code. It is tricky for the destination VM?
732 * - Another one is ...
733 * We update the information of the given VM to place it to the destination physical host.
735 * The second one would be easier.
738 simgrid::s4u::VirtualMachine* typedVm = static_cast<simgrid::s4u::VirtualMachine*>(vm);
739 simgrid::vm::VirtualMachineImpl* pimpl = typedVm->pimpl_vm_;
740 msg_host_t src_pm = pimpl->getPm();
743 THROWF(vm_error, 0, "Cannot migrate VM '%s' from host '%s', which is offline.", vm->cname(), src_pm->cname());
745 THROWF(vm_error, 0, "Cannot migrate VM '%s' to host '%s', which is offline.", vm->cname(), dst_pm->cname());
746 if (not MSG_vm_is_running(vm))
747 THROWF(vm_error, 0, "Cannot migrate VM '%s' that is not running yet.", vm->cname());
748 if (typedVm->isMigrating())
749 THROWF(vm_error, 0, "Cannot migrate VM '%s' that is already migrating.", vm->cname());
751 pimpl->isMigrating = true;
753 struct migration_session *ms = xbt_new(struct migration_session, 1);
758 /* We have two mailboxes. mbox is used to transfer migration data between source and destination PMs. mbox_ctl is used
759 * to detect the completion of a migration. The names of these mailboxes must not conflict with others. */
760 ms->mbox_ctl = bprintf("__mbox_mig_ctl:%s(%s-%s)", vm->cname(), src_pm->cname(), dst_pm->cname());
761 ms->mbox = bprintf("__mbox_mig_src_dst:%s(%s-%s)", vm->cname(), src_pm->cname(), dst_pm->cname());
763 char *pr_rx_name = get_mig_process_rx_name(vm, src_pm, dst_pm);
764 char *pr_tx_name = get_mig_process_tx_name(vm, src_pm, dst_pm);
766 char** argv = xbt_new(char*, 2);
767 argv[0] = pr_rx_name;
769 MSG_process_create_with_arguments(pr_rx_name, migration_rx_fun, ms, dst_pm, 1, argv);
771 argv = xbt_new(char*, 2);
772 argv[0] = pr_tx_name;
774 MSG_process_create_with_arguments(pr_tx_name, migration_tx_fun, ms, src_pm, 1, argv);
776 /* wait until the migration have finished or on error has occurred */
777 XBT_DEBUG("wait for reception of the final ACK (i.e. migration has been correctly performed");
778 msg_task_t task = nullptr;
779 msg_error_t ret = MSG_task_receive(&task, ms->mbox_ctl);
781 pimpl->isMigrating = false;
783 xbt_free(ms->mbox_ctl);
787 if (ret == MSG_HOST_FAILURE) {
788 // Note that since the communication failed, the owner did not change and the task should be destroyed on the
789 // other side. Hence, just throw the execption
790 XBT_ERROR("SRC crashes, throw an exception (m-control)");
791 // MSG_process_kill(tx_process); // Adrien, I made a merge on Nov 28th 2014, I'm not sure whether this line is
793 THROWF(host_error, 0, "Source host '%s' failed during the migration of VM '%s'.", src_pm->cname(), vm->cname());
794 } else if ((ret == MSG_TRANSFER_FAILURE) || (ret == MSG_TIMEOUT)) {
795 // MSG_TIMEOUT here means that MSG_host_is_avail() returned false.
796 XBT_ERROR("DST crashes, throw an exception (m-control)");
797 THROWF(host_error, 0, "Destination host '%s' failed during the migration of VM '%s'.", dst_pm->cname(),
801 char* expected_task_name = get_mig_task_name(vm, src_pm, dst_pm, 4);
802 xbt_assert(strcmp(task->name, expected_task_name) == 0);
803 xbt_free(expected_task_name);
804 MSG_task_destroy(task);
807 /** @brief Immediately suspend the execution of all processes within the given VM.
810 * This function stops the execution of the VM. All the processes on this VM
811 * will pause. The state of the VM is preserved. We can later resume it again.
813 * No suspension cost occurs.
815 void MSG_vm_suspend(msg_vm_t vm)
817 smx_actor_t issuer = SIMIX_process_self();
818 simgrid::simix::kernelImmediate([vm,issuer]() {
819 static_cast<simgrid::s4u::VirtualMachine*>(vm)->pimpl_vm_->suspend(issuer);
822 XBT_DEBUG("vm_suspend done");
824 if (TRACE_msg_vm_is_enabled()) {
825 container_t vm_container = PJ_container_get(vm->cname());
826 type_t type = PJ_type_get("MSG_VM_STATE", vm_container->type);
827 val_t value = PJ_value_get_or_new("suspend", "1 0 0", type); // suspend is red
828 new PushStateEvent(MSG_get_clock(), vm_container, type, value);
832 /** @brief Resume the execution of the VM. All processes on the VM run again.
835 * No resume cost occurs.
837 void MSG_vm_resume(msg_vm_t vm)
839 static_cast<simgrid::s4u::VirtualMachine*>(vm)->pimpl_vm_->resume();
841 if (TRACE_msg_vm_is_enabled()) {
842 container_t vm_container = PJ_container_get(vm->cname());
843 type_t type = PJ_type_get("MSG_VM_STATE", vm_container->type);
844 new PopStateEvent(MSG_get_clock(), vm_container, type);
848 /** @brief Get the physical host of a given VM.
851 msg_host_t MSG_vm_get_pm(msg_vm_t vm)
853 return static_cast<simgrid::s4u::VirtualMachine*>(vm)->pm();
856 /** @brief Set a CPU bound for a given VM.
859 * 1. Note that in some cases MSG_task_set_bound() may not intuitively work for VMs.
862 * On PM0, there are Task1 and VM0.
863 * On VM0, there is Task2.
864 * Now we bound 75% to Task1\@PM0 and bound 25% to Task2\@VM0.
866 * Task1\@PM0 gets 50%.
867 * Task2\@VM0 gets 25%.
868 * This is NOT 75% for Task1\@PM0 and 25% for Task2\@VM0, respectively.
870 * This is because a VM has the dummy CPU action in the PM layer. Putting a task on the VM does not affect the bound of
871 * the dummy CPU action. The bound of the dummy CPU action is unlimited.
873 * There are some solutions for this problem. One option is to update the bound of the dummy CPU action automatically.
874 * It should be the sum of all tasks on the VM. But, this solution might be costly, because we have to scan all tasks
875 * on the VM in share_resource() or we have to trap both the start and end of task execution.
877 * The current solution is to use MSG_vm_set_bound(), which allows us to directly set the bound of the dummy CPU action.
879 * 2. Note that bound == 0 means no bound (i.e., unlimited). But, if a host has multiple CPU cores, the CPU share of a
880 * computation task (or a VM) never exceeds the capacity of a CPU core.
882 void MSG_vm_set_bound(msg_vm_t vm, double bound)
884 simgrid::simix::kernelImmediate(
885 [vm, bound]() { static_cast<simgrid::s4u::VirtualMachine*>(vm)->pimpl_vm_->setBound(bound); });