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43 #include "types/enums.h"
44 #include "types/hw_info.h"
45 #include "types/commrec.h"
46 #include "gmx_fatal.h"
47 #include "gmx_fatal_collective.h"
49 #include "gpu_utils.h"
51 #include "gmx_detect_hardware.h"
53 #include "md_logging.h"
55 #include "thread_mpi/threads.h"
57 #if ((defined(WIN32) || defined( _WIN32 ) || defined(WIN64) || defined( _WIN64 )) && !(defined (__CYGWIN__) || defined (__CYGWIN32__)))
62 const gmx_bool bGPUBinary = TRUE;
64 const gmx_bool bGPUBinary = FALSE;
67 static const char * invalid_gpuid_hint =
68 "A delimiter-free sequence of valid numeric IDs of available GPUs is expected.";
70 /* The globally shared hwinfo structure. */
71 static gmx_hw_info_t *hwinfo_g;
72 /* A reference counter for the hwinfo structure */
73 static int n_hwinfo = 0;
74 /* A lock to protect the hwinfo structure */
75 static tMPI_Thread_mutex_t hw_info_lock = TMPI_THREAD_MUTEX_INITIALIZER;
79 static void limit_num_gpus_used(gmx_gpu_opt_t *gpu_opt, int count);
80 static int gmx_count_gpu_dev_unique(const gmx_gpu_info_t *gpu_info,
81 const gmx_gpu_opt_t *gpu_opt);
83 static void sprint_gpus(char *sbuf, const gmx_gpu_info_t *gpu_info, gmx_bool bPrintAll)
88 ndev = gpu_info->ncuda_dev;
91 for (i = 0; i < ndev; i++)
93 get_gpu_device_info_string(stmp, gpu_info, i);
103 static void print_gpu_detection_stats(FILE *fplog,
104 const gmx_gpu_info_t *gpu_info,
107 char onhost[266], stmp[STRLEN];
110 if (!gpu_info->bDetectGPUs)
112 /* We skipped the detection, so don't print detection stats */
116 ngpu = gpu_info->ncuda_dev;
118 #if defined GMX_MPI && !defined GMX_THREAD_MPI
119 /* We only print the detection on one, of possibly multiple, nodes */
120 strncpy(onhost, " on host ", 10);
121 gmx_gethostname(onhost+9, 256);
123 /* We detect all relevant GPUs */
124 strncpy(onhost, "", 1);
129 sprint_gpus(stmp, gpu_info, TRUE);
130 md_print_warn(cr, fplog, "%d GPU%s detected%s:\n%s\n",
131 ngpu, (ngpu > 1) ? "s" : "", onhost, stmp);
135 md_print_warn(cr, fplog, "No GPUs detected%s\n", onhost);
139 static void print_gpu_use_stats(FILE *fplog,
140 const gmx_gpu_info_t *gpu_info,
141 const gmx_gpu_opt_t *gpu_opt,
144 char sbuf[STRLEN], stmp[STRLEN];
145 int i, ngpu_comp, ngpu_use;
147 ngpu_comp = gpu_info->ncuda_dev_compatible;
148 ngpu_use = gpu_opt->ncuda_dev_use;
150 /* Issue a note if GPUs are available but not used */
151 if (ngpu_comp > 0 && ngpu_use < 1)
154 "%d compatible GPU%s detected in the system, but none will be used.\n"
155 "Consider trying GPU acceleration with the Verlet scheme!",
156 ngpu_comp, (ngpu_comp > 1) ? "s" : "");
162 ngpu_use_uniq = gmx_count_gpu_dev_unique(gpu_info, gpu_opt);
164 sprintf(sbuf, "%d GPU%s %sselected for this run.\n"
165 "Mapping of GPU%s to the %d PP rank%s in this node: ",
166 ngpu_use_uniq, (ngpu_use_uniq > 1) ? "s" : "",
167 gpu_opt->bUserSet ? "user-" : "auto-",
168 (ngpu_use > 1) ? "s" : "",
169 cr->nrank_pp_intranode,
170 (cr->nrank_pp_intranode > 1) ? "s" : "");
172 for (i = 0; i < ngpu_use; i++)
174 sprintf(stmp, "#%d", get_gpu_device_id(gpu_info, gpu_opt, i));
175 if (i < ngpu_use - 1)
182 md_print_info(cr, fplog, "%s\n\n", sbuf);
185 /* Parse a "plain" GPU ID string which contains a sequence of digits corresponding
186 * to GPU IDs; the order will indicate the process/tMPI thread - GPU assignment. */
187 static void parse_gpu_id_plain_string(const char *idstr, int *nid, int **idlist)
191 *nid = strlen(idstr);
195 for (i = 0; i < *nid; i++)
197 if (idstr[i] < '0' || idstr[i] > '9')
199 gmx_fatal(FARGS, "Invalid character in GPU ID string: '%c'\n%s\n",
200 idstr[i], invalid_gpuid_hint);
202 (*idlist)[i] = idstr[i] - '0';
206 static void parse_gpu_id_csv_string(const char *idstr, int *nid, int *idlist)
208 /* XXX implement cvs format to support more than 10 different GPUs in a box. */
209 gmx_incons("Not implemented yet");
212 void gmx_check_hw_runconf_consistency(FILE *fplog,
213 const gmx_hw_info_t *hwinfo,
215 const gmx_hw_opt_t *hw_opt,
219 char sbuf[STRLEN], th_or_proc[STRLEN], th_or_proc_plural[STRLEN], pernode[STRLEN];
220 gmx_bool btMPI, bMPI, bMaxMpiThreadsSet, bNthreadsAuto, bEmulateGPU;
225 /* Below we only do consistency checks for PP and GPUs,
226 * this is irrelevant for PME only nodes, so in that case we return
229 if (!(cr->duty & DUTY_PP))
234 btMPI = bMPI = FALSE;
235 bNthreadsAuto = FALSE;
236 #if defined(GMX_THREAD_MPI)
238 bNthreadsAuto = (hw_opt->nthreads_tmpi < 1);
239 #elif defined(GMX_LIB_MPI)
243 /* GPU emulation detection is done later, but we need here as well
244 * -- uncool, but there's no elegant workaround */
245 bEmulateGPU = (getenv("GMX_EMULATE_GPU") != NULL);
246 bMaxMpiThreadsSet = (getenv("GMX_MAX_MPI_THREADS") != NULL);
248 /* check the acceleration mdrun is compiled with against hardware
250 /* TODO: Here we assume homogeneous hardware which is not necessarily
251 the case! Might not hurt to add an extra check over MPI. */
252 gmx_cpuid_acceleration_check(hwinfo->cpuid_info, fplog, SIMMASTER(cr));
254 /* NOTE: this print is only for and on one physical node */
255 print_gpu_detection_stats(fplog, &hwinfo->gpu_info, cr);
257 if (hwinfo->gpu_info.ncuda_dev_compatible > 0)
259 /* NOTE: this print is only for and on one physical node */
260 print_gpu_use_stats(fplog, &hwinfo->gpu_info, &hw_opt->gpu_opt, cr);
263 /* Need to ensure that we have enough GPUs:
264 * - need one GPU per PP node
265 * - no GPU oversubscription with tMPI
267 /* number of PP processes per node */
268 npppn = cr->nrank_pp_intranode;
271 th_or_proc_plural[0] = '\0';
274 sprintf(th_or_proc, "thread-MPI thread");
277 sprintf(th_or_proc_plural, "s");
282 sprintf(th_or_proc, "MPI process");
285 sprintf(th_or_proc_plural, "es");
287 sprintf(pernode, " per node");
291 /* neither MPI nor tMPI */
292 sprintf(th_or_proc, "process");
295 if (bUseGPU && hwinfo->gpu_info.ncuda_dev_compatible > 0 &&
298 int ngpu_comp, ngpu_use;
299 char gpu_comp_plural[2], gpu_use_plural[2];
301 ngpu_comp = hwinfo->gpu_info.ncuda_dev_compatible;
302 ngpu_use = hw_opt->gpu_opt.ncuda_dev_use;
304 sprintf(gpu_comp_plural, "%s", (ngpu_comp> 1) ? "s" : "");
305 sprintf(gpu_use_plural, "%s", (ngpu_use > 1) ? "s" : "");
307 /* number of tMPI threads auto-adjusted */
308 if (btMPI && bNthreadsAuto)
310 if (hw_opt->gpu_opt.bUserSet && npppn < ngpu_use)
312 /* The user manually provided more GPUs than threads we
313 could automatically start. */
315 "%d GPU%s provided, but only %d PP thread-MPI thread%s coud be started.\n"
316 "%s requires one PP tread-MPI thread per GPU; use fewer GPUs%s.",
317 ngpu_use, gpu_use_plural,
318 npppn, th_or_proc_plural,
319 ShortProgram(), bMaxMpiThreadsSet ? "\nor allow more threads to be used" : "");
322 if (!hw_opt->gpu_opt.bUserSet && npppn < ngpu_comp)
324 /* There are more GPUs than tMPI threads; we have
325 limited the number GPUs used. */
326 md_print_warn(cr, fplog,
327 "NOTE: %d GPU%s were detected, but only %d PP thread-MPI thread%s can be started.\n"
328 " %s can use one GPU per PP tread-MPI thread, so only %d GPU%s will be used.%s\n",
329 ngpu_comp, gpu_comp_plural,
330 npppn, th_or_proc_plural,
331 ShortProgram(), npppn,
332 npppn > 1 ? "s" : "",
333 bMaxMpiThreadsSet ? "\n Also, you can allow more threads to be used by increasing GMX_MAX_MPI_THREADS" : "");
337 if (hw_opt->gpu_opt.bUserSet)
339 if (ngpu_use != npppn)
342 "Incorrect launch configuration: mismatching number of PP %s%s and GPUs%s.\n"
343 "%s was started with %d PP %s%s%s, but you provided %d GPU%s.",
344 th_or_proc, btMPI ? "s" : "es", pernode,
345 ShortProgram(), npppn, th_or_proc,
346 th_or_proc_plural, pernode,
347 ngpu_use, gpu_use_plural);
352 if (ngpu_comp > npppn)
354 md_print_warn(cr, fplog,
355 "NOTE: potentially sub-optimal launch configuration, %s started with less\n"
356 " PP %s%s%s than GPU%s available.\n"
357 " Each PP %s can use only one GPU, %d GPU%s%s will be used.\n",
358 ShortProgram(), th_or_proc,
359 th_or_proc_plural, pernode, gpu_comp_plural,
360 th_or_proc, npppn, gpu_use_plural, pernode);
363 if (ngpu_use != npppn)
365 /* Avoid duplicate error messages.
366 * Unfortunately we can only do this at the physical node
367 * level, since the hardware setup and MPI process count
368 * might differ between physical nodes.
370 if (cr->rank_pp_intranode == 0)
373 "Incorrect launch configuration: mismatching number of PP %s%s and GPUs%s.\n"
374 "%s was started with %d PP %s%s%s, but only %d GPU%s were detected.",
375 th_or_proc, btMPI ? "s" : "es", pernode,
376 ShortProgram(), npppn, th_or_proc,
377 th_or_proc_plural, pernode,
378 ngpu_use, gpu_use_plural);
386 same_count = gmx_count_gpu_dev_shared(&hw_opt->gpu_opt);
390 md_print_info(cr, fplog,
391 "NOTE: You assigned %s to multiple %s%s.\n",
392 same_count > 1 ? "GPUs" : "a GPU", th_or_proc, btMPI ? "s" : "es");
400 /* Avoid other ranks to continue after
402 MPI_Barrier(cr->mpi_comm_mygroup);
408 /* Return 0 if none of the GPU (per node) are shared among PP ranks.
410 * Sharing GPUs among multiple PP ranks is possible when the user passes
411 * GPU IDs. Here we check for sharing and return a non-zero value when
412 * this is detected. Note that the return value represents the number of
413 * PP rank pairs that share a device.
415 int gmx_count_gpu_dev_shared(const gmx_gpu_opt_t *gpu_opt)
418 int ngpu = gpu_opt->ncuda_dev_use;
420 if (gpu_opt->bUserSet)
424 for (i = 0; i < ngpu - 1; i++)
426 for (j = i + 1; j < ngpu; j++)
428 same_count += (gpu_opt->cuda_dev_use[i] ==
429 gpu_opt->cuda_dev_use[j]);
437 /* Count and return the number of unique GPUs (per node) selected.
439 * As sharing GPUs among multiple PP ranks is possible when the user passes
440 * GPU IDs, the number of GPUs user (per node) can be different from the
441 * number of GPU IDs selected.
443 static int gmx_count_gpu_dev_unique(const gmx_gpu_info_t *gpu_info,
444 const gmx_gpu_opt_t *gpu_opt)
446 int i, uniq_count, ngpu;
452 ngpu = gpu_info->ncuda_dev;
455 snew(uniq_ids, ngpu);
457 /* Each element in uniq_ids will be set to 0 or 1. The n-th element set
458 * to 1 indicates that the respective GPU was selected to be used. */
459 for (i = 0; i < gpu_opt->ncuda_dev_use; i++)
461 uniq_ids[get_gpu_device_id(gpu_info, gpu_opt, i)] = 1;
463 /* Count the devices used. */
464 for (i = 0; i < ngpu; i++)
466 uniq_count += uniq_ids[i];
475 /* Return the number of hardware threads supported by the current CPU.
476 * We assume that this is equal with the number of CPUs reported to be
477 * online by the OS at the time of the call.
479 static int get_nthreads_hw_avail(FILE *fplog, const t_commrec *cr)
483 #if ((defined(WIN32) || defined( _WIN32 ) || defined(WIN64) || defined( _WIN64 )) && !(defined (__CYGWIN__) || defined (__CYGWIN32__)))
486 GetSystemInfo( &sysinfo );
487 ret = sysinfo.dwNumberOfProcessors;
488 #elif defined HAVE_SYSCONF
489 /* We are probably on Unix.
490 * Now check if we have the argument to use before executing the call
492 #if defined(_SC_NPROCESSORS_ONLN)
493 ret = sysconf(_SC_NPROCESSORS_ONLN);
494 #elif defined(_SC_NPROC_ONLN)
495 ret = sysconf(_SC_NPROC_ONLN);
496 #elif defined(_SC_NPROCESSORS_CONF)
497 ret = sysconf(_SC_NPROCESSORS_CONF);
498 #elif defined(_SC_NPROC_CONF)
499 ret = sysconf(_SC_NPROC_CONF);
500 #endif /* End of check for sysconf argument values */
503 /* Neither windows nor Unix. No fscking idea how many CPUs we have! */
509 fprintf(debug, "Detected %d processors, will use this as the number "
510 "of supported hardware threads.\n", ret);
514 if (ret != gmx_omp_get_num_procs())
516 md_print_warn(cr, fplog,
517 "Number of CPUs detected (%d) does not match the number reported by OpenMP (%d).\n"
518 "Consider setting the launch configuration manually!",
519 ret, gmx_omp_get_num_procs());
526 static void gmx_detect_gpus(FILE *fplog, const t_commrec *cr,
527 gmx_gpu_info_t *gpu_info)
531 MPI_Comm physicalnode_comm;
535 /* Under certain circumstances MPI ranks on the same physical node
536 * can not simultaneously access the same GPU(s). Therefore we run
537 * the detection only on one MPI rank per node and broadcast the info.
538 * Note that with thread-MPI only a single thread runs this code.
540 * TODO: We should also do CPU hardware detection only once on each
541 * physical node and broadcast it, instead of do it on every MPI rank.
544 /* A split of MPI_COMM_WORLD over physical nodes is only required here,
545 * so we create and destroy it locally.
547 MPI_Comm_rank(MPI_COMM_WORLD, &rank_world);
548 MPI_Comm_split(MPI_COMM_WORLD, gmx_physicalnode_id_hash(),
549 rank_world, &physicalnode_comm);
550 MPI_Comm_rank(physicalnode_comm, &rank_local);
552 /* Here there should be only one process, check this */
553 assert(cr->nnodes == 1 && cr->sim_nodeid == 0);
560 char detection_error[STRLEN], sbuf[STRLEN];
562 if (detect_cuda_gpus(&hwinfo_g->gpu_info, detection_error) != 0)
564 if (detection_error != NULL && detection_error[0] != '\0')
566 sprintf(sbuf, ":\n %s\n", detection_error);
572 md_print_warn(cr, fplog,
573 "NOTE: Error occurred during GPU detection%s"
574 " Can not use GPU acceleration, will fall back to CPU kernels.\n",
580 /* Broadcast the GPU info to the other ranks within this node */
581 MPI_Bcast(&hwinfo_g->gpu_info.ncuda_dev, 1, MPI_INT, 0, physicalnode_comm);
583 if (hwinfo_g->gpu_info.ncuda_dev > 0)
587 cuda_dev_size = hwinfo_g->gpu_info.ncuda_dev*sizeof_cuda_dev_info();
591 hwinfo_g->gpu_info.cuda_dev =
592 (cuda_dev_info_ptr_t)malloc(cuda_dev_size);
594 MPI_Bcast(hwinfo_g->gpu_info.cuda_dev, cuda_dev_size, MPI_BYTE,
595 0, physicalnode_comm);
596 MPI_Bcast(&hwinfo_g->gpu_info.ncuda_dev_compatible, 1, MPI_INT,
597 0, physicalnode_comm);
600 MPI_Comm_free(&physicalnode_comm);
604 gmx_hw_info_t *gmx_detect_hardware(FILE *fplog, const t_commrec *cr,
605 gmx_bool bDetectGPUs)
610 /* make sure no one else is doing the same thing */
611 ret = tMPI_Thread_mutex_lock(&hw_info_lock);
614 gmx_fatal(FARGS, "Error locking hwinfo mutex: %s", strerror(errno));
617 /* only initialize the hwinfo structure if it is not already initalized */
622 /* detect CPUID info; no fuss, we don't detect system-wide
623 * -- sloppy, but that's it for now */
624 if (gmx_cpuid_init(&hwinfo_g->cpuid_info) != 0)
626 gmx_fatal_collective(FARGS, cr, NULL, "CPUID detection failed!");
629 /* detect number of hardware threads */
630 hwinfo_g->nthreads_hw_avail = get_nthreads_hw_avail(fplog, cr);
633 hwinfo_g->gpu_info.ncuda_dev = 0;
634 hwinfo_g->gpu_info.cuda_dev = NULL;
635 hwinfo_g->gpu_info.ncuda_dev_compatible = 0;
637 /* Run the detection if the binary was compiled with GPU support
638 * and we requested detection.
640 hwinfo_g->gpu_info.bDetectGPUs =
641 (bGPUBinary && bDetectGPUs &&
642 getenv("GMX_DISABLE_GPU_DETECTION") == NULL);
643 if (hwinfo_g->gpu_info.bDetectGPUs)
645 gmx_detect_gpus(fplog, cr, &hwinfo_g->gpu_info);
648 /* increase the reference counter */
651 ret = tMPI_Thread_mutex_unlock(&hw_info_lock);
654 gmx_fatal(FARGS, "Error unlocking hwinfo mutex: %s", strerror(errno));
660 void gmx_parse_gpu_ids(gmx_gpu_opt_t *gpu_opt)
664 if (gpu_opt->gpu_id != NULL && !bGPUBinary)
666 gmx_fatal(FARGS, "GPU ID string set, but %s was compiled without GPU support!", ShortProgram());
669 env = getenv("GMX_GPU_ID");
670 if (env != NULL && gpu_opt->gpu_id != NULL)
672 gmx_fatal(FARGS, "GMX_GPU_ID and -gpu_id can not be used at the same time");
676 env = gpu_opt->gpu_id;
679 /* parse GPU IDs if the user passed any */
682 parse_gpu_id_plain_string(env,
683 &gpu_opt->ncuda_dev_use,
684 &gpu_opt->cuda_dev_use);
686 if (gpu_opt->ncuda_dev_use == 0)
688 gmx_fatal(FARGS, "Empty GPU ID string encountered.\n%s\n",
692 gpu_opt->bUserSet = TRUE;
696 void gmx_select_gpu_ids(FILE *fplog, const t_commrec *cr,
697 const gmx_gpu_info_t *gpu_info,
698 gmx_bool bForceUseGPU,
699 gmx_gpu_opt_t *gpu_opt)
703 char sbuf[STRLEN], stmp[STRLEN];
705 /* Bail if binary is not compiled with GPU acceleration, but this is either
706 * explicitly (-nb gpu) or implicitly (gpu ID passed) requested. */
707 if (bForceUseGPU && !bGPUBinary)
709 gmx_fatal(FARGS, "GPU acceleration requested, but %s was compiled without GPU support!", ShortProgram());
712 if (gpu_opt->bUserSet)
714 /* Check the GPU IDs passed by the user.
715 * (GPU IDs have been parsed by gmx_parse_gpu_ids before)
720 snew(checkres, gpu_opt->ncuda_dev_use);
722 res = check_selected_cuda_gpus(checkres, gpu_info, gpu_opt);
726 print_gpu_detection_stats(fplog, gpu_info, cr);
728 sprintf(sbuf, "Some of the requested GPUs do not exist, behave strangely, or are not compatible:\n");
729 for (i = 0; i < gpu_opt->ncuda_dev_use; i++)
731 if (checkres[i] != egpuCompatible)
733 sprintf(stmp, " GPU #%d: %s\n",
734 gpu_opt->cuda_dev_use[i],
735 gpu_detect_res_str[checkres[i]]);
739 gmx_fatal(FARGS, "%s", sbuf);
746 pick_compatible_gpus(&hwinfo_g->gpu_info, gpu_opt);
748 if (gpu_opt->ncuda_dev_use > cr->nrank_pp_intranode)
750 /* We picked more GPUs than we can use: limit the number.
751 * We print detailed messages about this later in
752 * gmx_check_hw_runconf_consistency.
754 limit_num_gpus_used(gpu_opt, cr->nrank_pp_intranode);
757 gpu_opt->bUserSet = FALSE;
760 /* If the user asked for a GPU, check whether we have a GPU */
761 if (bForceUseGPU && gpu_info->ncuda_dev_compatible == 0)
763 gmx_fatal(FARGS, "GPU acceleration requested, but no compatible GPUs were detected.");
767 static void limit_num_gpus_used(gmx_gpu_opt_t *gpu_opt, int count)
773 ndev_use = gpu_opt->ncuda_dev_use;
775 if (count > ndev_use)
777 /* won't increase the # of GPUs */
784 sprintf(sbuf, "Limiting the number of GPUs to <1 doesn't make sense (detected %d, %d requested)!",
789 /* TODO: improve this implementation: either sort GPUs or remove the weakest here */
790 gpu_opt->ncuda_dev_use = count;
793 void gmx_hardware_info_free(gmx_hw_info_t *hwinfo)
797 ret = tMPI_Thread_mutex_lock(&hw_info_lock);
800 gmx_fatal(FARGS, "Error locking hwinfo mutex: %s", strerror(errno));
803 /* decrease the reference counter */
807 if (hwinfo != hwinfo_g)
809 gmx_incons("hwinfo < hwinfo_g");
814 gmx_incons("n_hwinfo < 0");
819 gmx_cpuid_done(hwinfo_g->cpuid_info);
820 free_gpu_info(&hwinfo_g->gpu_info);
824 ret = tMPI_Thread_mutex_unlock(&hw_info_lock);
827 gmx_fatal(FARGS, "Error unlocking hwinfo mutex: %s", strerror(errno));