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48 #include "types/enums.h"
49 #include "types/hw_info.h"
50 #include "types/commrec.h"
51 #include "gmx_fatal.h"
52 #include "gmx_fatal_collective.h"
53 #include "md_logging.h"
54 #include "gmx_cpuid.h"
55 #include "gromacs/utility/smalloc.h"
56 #include "gpu_utils.h"
58 #include "gmx_detect_hardware.h"
60 #include "md_logging.h"
61 #include "gromacs/utility/gmxomp.h"
63 #include "thread_mpi/threads.h"
65 #ifdef GMX_NATIVE_WINDOWS
70 const gmx_bool bGPUBinary = TRUE;
72 const gmx_bool bGPUBinary = FALSE;
75 static const char * invalid_gpuid_hint =
76 "A delimiter-free sequence of valid numeric IDs of available GPUs is expected.";
78 /* The globally shared hwinfo structure. */
79 static gmx_hw_info_t *hwinfo_g;
80 /* A reference counter for the hwinfo structure */
81 static int n_hwinfo = 0;
82 /* A lock to protect the hwinfo structure */
83 static tMPI_Thread_mutex_t hw_info_lock = TMPI_THREAD_MUTEX_INITIALIZER;
87 static void limit_num_gpus_used(gmx_gpu_opt_t *gpu_opt, int count);
88 static int gmx_count_gpu_dev_unique(const gmx_gpu_info_t *gpu_info,
89 const gmx_gpu_opt_t *gpu_opt);
91 static void sprint_gpus(char *sbuf, const gmx_gpu_info_t *gpu_info)
96 ndev = gpu_info->ncuda_dev;
99 for (i = 0; i < ndev; i++)
101 get_gpu_device_info_string(stmp, gpu_info, i);
111 static void print_gpu_detection_stats(FILE *fplog,
112 const gmx_gpu_info_t *gpu_info,
115 char onhost[266], stmp[STRLEN];
118 if (!gpu_info->bDetectGPUs)
120 /* We skipped the detection, so don't print detection stats */
124 ngpu = gpu_info->ncuda_dev;
126 #if defined GMX_MPI && !defined GMX_THREAD_MPI
127 /* We only print the detection on one, of possibly multiple, nodes */
128 strncpy(onhost, " on host ", 10);
129 gmx_gethostname(onhost+9, 256);
131 /* We detect all relevant GPUs */
132 strncpy(onhost, "", 1);
137 sprint_gpus(stmp, gpu_info);
138 md_print_warn(cr, fplog, "%d GPU%s detected%s:\n%s\n",
139 ngpu, (ngpu > 1) ? "s" : "", onhost, stmp);
143 md_print_warn(cr, fplog, "No GPUs detected%s\n", onhost);
147 static void print_gpu_use_stats(FILE *fplog,
148 const gmx_gpu_info_t *gpu_info,
149 const gmx_gpu_opt_t *gpu_opt,
152 char sbuf[STRLEN], stmp[STRLEN];
153 int i, ngpu_comp, ngpu_use;
155 ngpu_comp = gpu_info->ncuda_dev_compatible;
156 ngpu_use = gpu_opt->ncuda_dev_use;
158 /* Issue a note if GPUs are available but not used */
159 if (ngpu_comp > 0 && ngpu_use < 1)
162 "%d compatible GPU%s detected in the system, but none will be used.\n"
163 "Consider trying GPU acceleration with the Verlet scheme!",
164 ngpu_comp, (ngpu_comp > 1) ? "s" : "");
170 ngpu_use_uniq = gmx_count_gpu_dev_unique(gpu_info, gpu_opt);
172 sprintf(sbuf, "%d GPU%s %sselected for this run.\n"
173 "Mapping of GPU%s to the %d PP rank%s in this node: ",
174 ngpu_use_uniq, (ngpu_use_uniq > 1) ? "s" : "",
175 gpu_opt->bUserSet ? "user-" : "auto-",
176 (ngpu_use > 1) ? "s" : "",
177 cr->nrank_pp_intranode,
178 (cr->nrank_pp_intranode > 1) ? "s" : "");
180 for (i = 0; i < ngpu_use; i++)
182 sprintf(stmp, "#%d", get_gpu_device_id(gpu_info, gpu_opt, i));
183 if (i < ngpu_use - 1)
190 md_print_info(cr, fplog, "%s\n\n", sbuf);
193 /* Parse a "plain" GPU ID string which contains a sequence of digits corresponding
194 * to GPU IDs; the order will indicate the process/tMPI thread - GPU assignment. */
195 static void parse_gpu_id_plain_string(const char *idstr, int *nid, int **idlist)
199 *nid = strlen(idstr);
203 for (i = 0; i < *nid; i++)
205 if (idstr[i] < '0' || idstr[i] > '9')
207 gmx_fatal(FARGS, "Invalid character in GPU ID string: '%c'\n%s\n",
208 idstr[i], invalid_gpuid_hint);
210 (*idlist)[i] = idstr[i] - '0';
214 static void parse_gpu_id_csv_string(const char gmx_unused *idstr, int gmx_unused *nid, int gmx_unused *idlist)
216 /* XXX implement cvs format to support more than 10 different GPUs in a box. */
217 gmx_incons("Not implemented yet");
220 /* Give a suitable fatal error or warning if the build configuration
221 and runtime CPU do not match. */
223 check_use_of_rdtscp_on_this_cpu(FILE *fplog,
225 const gmx_hw_info_t *hwinfo)
227 gmx_bool bCpuHasRdtscp, bBinaryUsesRdtscp;
229 bBinaryUsesRdtscp = TRUE;
231 bBinaryUsesRdtscp = FALSE;
234 bCpuHasRdtscp = gmx_cpuid_feature(hwinfo->cpuid_info, GMX_CPUID_FEATURE_X86_RDTSCP);
236 if (!bCpuHasRdtscp && bBinaryUsesRdtscp)
238 gmx_fatal(FARGS, "The %s executable was compiled to use the rdtscp CPU instruction. "
239 "However, this is not supported by the current hardware and continuing would lead to a crash. "
240 "Please rebuild GROMACS with the GMX_USE_RDTSCP=OFF CMake option.",
244 if (bCpuHasRdtscp && !bBinaryUsesRdtscp)
246 md_print_warn(cr, fplog, "The current CPU can measure timings more accurately than the code in\n"
247 "%s was configured to use. This might affect your simulation\n"
248 "speed as accurate timings are needed for load-balancing.\n"
249 "Please consider rebuilding %s with the GMX_USE_RDTSCP=OFF CMake option.\n",
250 ShortProgram(), ShortProgram());
254 void gmx_check_hw_runconf_consistency(FILE *fplog,
255 const gmx_hw_info_t *hwinfo,
257 const gmx_hw_opt_t *hw_opt,
261 char sbuf[STRLEN], th_or_proc[STRLEN], th_or_proc_plural[STRLEN], pernode[STRLEN];
262 gmx_bool btMPI, bMPI, bMaxMpiThreadsSet, bNthreadsAuto, bEmulateGPU;
267 /* Below we only do consistency checks for PP and GPUs,
268 * this is irrelevant for PME only nodes, so in that case we return
271 if (!(cr->duty & DUTY_PP))
276 btMPI = bMPI = FALSE;
277 bNthreadsAuto = FALSE;
278 #if defined(GMX_THREAD_MPI)
280 bNthreadsAuto = (hw_opt->nthreads_tmpi < 1);
281 #elif defined(GMX_LIB_MPI)
285 /* GPU emulation detection is done later, but we need here as well
286 * -- uncool, but there's no elegant workaround */
287 bEmulateGPU = (getenv("GMX_EMULATE_GPU") != NULL);
288 bMaxMpiThreadsSet = (getenv("GMX_MAX_MPI_THREADS") != NULL);
290 /* check the SIMD level mdrun is compiled with against hardware
292 /* TODO: Here we assume homogeneous hardware which is not necessarily
293 the case! Might not hurt to add an extra check over MPI. */
294 gmx_cpuid_simd_check(hwinfo->cpuid_info, fplog, SIMMASTER(cr));
296 check_use_of_rdtscp_on_this_cpu(fplog, cr, hwinfo);
298 /* NOTE: this print is only for and on one physical node */
299 print_gpu_detection_stats(fplog, &hwinfo->gpu_info, cr);
301 if (hwinfo->gpu_info.ncuda_dev_compatible > 0)
303 /* NOTE: this print is only for and on one physical node */
304 print_gpu_use_stats(fplog, &hwinfo->gpu_info, &hw_opt->gpu_opt, cr);
307 /* Need to ensure that we have enough GPUs:
308 * - need one GPU per PP node
309 * - no GPU oversubscription with tMPI
311 /* number of PP processes per node */
312 npppn = cr->nrank_pp_intranode;
315 th_or_proc_plural[0] = '\0';
318 sprintf(th_or_proc, "thread-MPI thread");
321 sprintf(th_or_proc_plural, "s");
326 sprintf(th_or_proc, "MPI process");
329 sprintf(th_or_proc_plural, "es");
331 sprintf(pernode, " per node");
335 /* neither MPI nor tMPI */
336 sprintf(th_or_proc, "process");
339 if (bUseGPU && hwinfo->gpu_info.ncuda_dev_compatible > 0 &&
342 int ngpu_comp, ngpu_use;
343 char gpu_comp_plural[2], gpu_use_plural[2];
345 ngpu_comp = hwinfo->gpu_info.ncuda_dev_compatible;
346 ngpu_use = hw_opt->gpu_opt.ncuda_dev_use;
348 sprintf(gpu_comp_plural, "%s", (ngpu_comp > 1) ? "s" : "");
349 sprintf(gpu_use_plural, "%s", (ngpu_use > 1) ? "s" : "");
351 /* number of tMPI threads auto-adjusted */
352 if (btMPI && bNthreadsAuto)
354 if (hw_opt->gpu_opt.bUserSet && npppn < ngpu_use)
356 /* The user manually provided more GPUs than threads we
357 could automatically start. */
359 "%d GPU%s provided, but only %d PP thread-MPI thread%s coud be started.\n"
360 "%s requires one PP tread-MPI thread per GPU; use fewer GPUs%s.",
361 ngpu_use, gpu_use_plural,
362 npppn, th_or_proc_plural,
363 ShortProgram(), bMaxMpiThreadsSet ? "\nor allow more threads to be used" : "");
366 if (!hw_opt->gpu_opt.bUserSet && npppn < ngpu_comp)
368 /* There are more GPUs than tMPI threads; we have
369 limited the number GPUs used. */
370 md_print_warn(cr, fplog,
371 "NOTE: %d GPU%s were detected, but only %d PP thread-MPI thread%s can be started.\n"
372 " %s can use one GPU per PP tread-MPI thread, so only %d GPU%s will be used.%s\n",
373 ngpu_comp, gpu_comp_plural,
374 npppn, th_or_proc_plural,
375 ShortProgram(), npppn,
376 npppn > 1 ? "s" : "",
377 bMaxMpiThreadsSet ? "\n Also, you can allow more threads to be used by increasing GMX_MAX_MPI_THREADS" : "");
381 if (hw_opt->gpu_opt.bUserSet)
383 if (ngpu_use != npppn)
386 "Incorrect launch configuration: mismatching number of PP %s%s and GPUs%s.\n"
387 "%s was started with %d PP %s%s%s, but you provided %d GPU%s.",
388 th_or_proc, btMPI ? "s" : "es", pernode,
389 ShortProgram(), npppn, th_or_proc,
390 th_or_proc_plural, pernode,
391 ngpu_use, gpu_use_plural);
396 if (ngpu_comp > npppn)
398 md_print_warn(cr, fplog,
399 "NOTE: potentially sub-optimal launch configuration, %s started with less\n"
400 " PP %s%s%s than GPU%s available.\n"
401 " Each PP %s can use only one GPU, %d GPU%s%s will be used.\n",
402 ShortProgram(), th_or_proc,
403 th_or_proc_plural, pernode, gpu_comp_plural,
404 th_or_proc, npppn, gpu_use_plural, pernode);
407 if (ngpu_use != npppn)
409 /* Avoid duplicate error messages.
410 * Unfortunately we can only do this at the physical node
411 * level, since the hardware setup and MPI process count
412 * might differ between physical nodes.
414 if (cr->rank_pp_intranode == 0)
417 "Incorrect launch configuration: mismatching number of PP %s%s and GPUs%s.\n"
418 "%s was started with %d PP %s%s%s, but only %d GPU%s were detected.",
419 th_or_proc, btMPI ? "s" : "es", pernode,
420 ShortProgram(), npppn, th_or_proc,
421 th_or_proc_plural, pernode,
422 ngpu_use, gpu_use_plural);
430 same_count = gmx_count_gpu_dev_shared(&hw_opt->gpu_opt);
434 md_print_info(cr, fplog,
435 "NOTE: You assigned %s to multiple %s%s.\n",
436 same_count > 1 ? "GPUs" : "a GPU", th_or_proc, btMPI ? "s" : "es");
444 /* Avoid other ranks to continue after
446 MPI_Barrier(cr->mpi_comm_mygroup);
452 /* Return 0 if none of the GPU (per node) are shared among PP ranks.
454 * Sharing GPUs among multiple PP ranks is possible when the user passes
455 * GPU IDs. Here we check for sharing and return a non-zero value when
456 * this is detected. Note that the return value represents the number of
457 * PP rank pairs that share a device.
459 int gmx_count_gpu_dev_shared(const gmx_gpu_opt_t *gpu_opt)
462 int ngpu = gpu_opt->ncuda_dev_use;
464 if (gpu_opt->bUserSet)
468 for (i = 0; i < ngpu - 1; i++)
470 for (j = i + 1; j < ngpu; j++)
472 same_count += (gpu_opt->cuda_dev_use[i] ==
473 gpu_opt->cuda_dev_use[j]);
481 /* Count and return the number of unique GPUs (per node) selected.
483 * As sharing GPUs among multiple PP ranks is possible when the user passes
484 * GPU IDs, the number of GPUs user (per node) can be different from the
485 * number of GPU IDs selected.
487 static int gmx_count_gpu_dev_unique(const gmx_gpu_info_t *gpu_info,
488 const gmx_gpu_opt_t *gpu_opt)
490 int i, uniq_count, ngpu;
496 ngpu = gpu_info->ncuda_dev;
499 snew(uniq_ids, ngpu);
501 /* Each element in uniq_ids will be set to 0 or 1. The n-th element set
502 * to 1 indicates that the respective GPU was selected to be used. */
503 for (i = 0; i < gpu_opt->ncuda_dev_use; i++)
505 uniq_ids[get_gpu_device_id(gpu_info, gpu_opt, i)] = 1;
507 /* Count the devices used. */
508 for (i = 0; i < ngpu; i++)
510 uniq_count += uniq_ids[i];
519 /* Return the number of hardware threads supported by the current CPU.
520 * We assume that this is equal with the number of CPUs reported to be
521 * online by the OS at the time of the call.
523 static int get_nthreads_hw_avail(FILE gmx_unused *fplog, const t_commrec gmx_unused *cr)
527 #if ((defined(WIN32) || defined( _WIN32 ) || defined(WIN64) || defined( _WIN64 )) && !(defined (__CYGWIN__) || defined (__CYGWIN32__)))
530 GetSystemInfo( &sysinfo );
531 ret = sysinfo.dwNumberOfProcessors;
532 #elif defined HAVE_SYSCONF
533 /* We are probably on Unix.
534 * Now check if we have the argument to use before executing the call
536 #if defined(_SC_NPROCESSORS_ONLN)
537 ret = sysconf(_SC_NPROCESSORS_ONLN);
538 #elif defined(_SC_NPROC_ONLN)
539 ret = sysconf(_SC_NPROC_ONLN);
540 #elif defined(_SC_NPROCESSORS_CONF)
541 ret = sysconf(_SC_NPROCESSORS_CONF);
542 #elif defined(_SC_NPROC_CONF)
543 ret = sysconf(_SC_NPROC_CONF);
545 #warning "No valid sysconf argument value found. Executables will not be able to determine the number of hardware threads: mdrun will use 1 thread by default!"
546 #endif /* End of check for sysconf argument values */
549 /* Neither windows nor Unix. No fscking idea how many CPUs we have! */
555 fprintf(debug, "Detected %d processors, will use this as the number "
556 "of supported hardware threads.\n", ret);
560 if (ret != gmx_omp_get_num_procs())
562 md_print_warn(cr, fplog,
563 "Number of CPUs detected (%d) does not match the number reported by OpenMP (%d).\n"
564 "Consider setting the launch configuration manually!",
565 ret, gmx_omp_get_num_procs());
572 static void gmx_detect_gpus(FILE *fplog, const t_commrec *cr)
576 MPI_Comm physicalnode_comm;
580 /* Under certain circumstances MPI ranks on the same physical node
581 * can not simultaneously access the same GPU(s). Therefore we run
582 * the detection only on one MPI rank per node and broadcast the info.
583 * Note that with thread-MPI only a single thread runs this code.
585 * TODO: We should also do CPU hardware detection only once on each
586 * physical node and broadcast it, instead of do it on every MPI rank.
589 /* A split of MPI_COMM_WORLD over physical nodes is only required here,
590 * so we create and destroy it locally.
592 MPI_Comm_rank(MPI_COMM_WORLD, &rank_world);
593 MPI_Comm_split(MPI_COMM_WORLD, gmx_physicalnode_id_hash(),
594 rank_world, &physicalnode_comm);
595 MPI_Comm_rank(physicalnode_comm, &rank_local);
597 /* Here there should be only one process, check this */
598 assert(cr->nnodes == 1 && cr->sim_nodeid == 0);
605 char detection_error[STRLEN] = "", sbuf[STRLEN];
607 if (detect_cuda_gpus(&hwinfo_g->gpu_info, detection_error) != 0)
609 if (detection_error != NULL && detection_error[0] != '\0')
611 sprintf(sbuf, ":\n %s\n", detection_error);
617 md_print_warn(cr, fplog,
618 "NOTE: Error occurred during GPU detection%s"
619 " Can not use GPU acceleration, will fall back to CPU kernels.\n",
625 /* Broadcast the GPU info to the other ranks within this node */
626 MPI_Bcast(&hwinfo_g->gpu_info.ncuda_dev, 1, MPI_INT, 0, physicalnode_comm);
628 if (hwinfo_g->gpu_info.ncuda_dev > 0)
632 cuda_dev_size = hwinfo_g->gpu_info.ncuda_dev*sizeof_cuda_dev_info();
636 hwinfo_g->gpu_info.cuda_dev =
637 (cuda_dev_info_ptr_t)malloc(cuda_dev_size);
639 MPI_Bcast(hwinfo_g->gpu_info.cuda_dev, cuda_dev_size, MPI_BYTE,
640 0, physicalnode_comm);
641 MPI_Bcast(&hwinfo_g->gpu_info.ncuda_dev_compatible, 1, MPI_INT,
642 0, physicalnode_comm);
645 MPI_Comm_free(&physicalnode_comm);
649 gmx_hw_info_t *gmx_detect_hardware(FILE *fplog, const t_commrec *cr,
650 gmx_bool bDetectGPUs)
655 /* make sure no one else is doing the same thing */
656 ret = tMPI_Thread_mutex_lock(&hw_info_lock);
659 gmx_fatal(FARGS, "Error locking hwinfo mutex: %s", strerror(errno));
662 /* only initialize the hwinfo structure if it is not already initalized */
667 /* detect CPUID info; no fuss, we don't detect system-wide
668 * -- sloppy, but that's it for now */
669 if (gmx_cpuid_init(&hwinfo_g->cpuid_info) != 0)
671 gmx_fatal_collective(FARGS, cr, NULL, "CPUID detection failed!");
674 /* detect number of hardware threads */
675 hwinfo_g->nthreads_hw_avail = get_nthreads_hw_avail(fplog, cr);
678 hwinfo_g->gpu_info.ncuda_dev = 0;
679 hwinfo_g->gpu_info.cuda_dev = NULL;
680 hwinfo_g->gpu_info.ncuda_dev_compatible = 0;
682 /* Run the detection if the binary was compiled with GPU support
683 * and we requested detection.
685 hwinfo_g->gpu_info.bDetectGPUs =
686 (bGPUBinary && bDetectGPUs &&
687 getenv("GMX_DISABLE_GPU_DETECTION") == NULL);
688 if (hwinfo_g->gpu_info.bDetectGPUs)
690 gmx_detect_gpus(fplog, cr);
693 /* increase the reference counter */
696 ret = tMPI_Thread_mutex_unlock(&hw_info_lock);
699 gmx_fatal(FARGS, "Error unlocking hwinfo mutex: %s", strerror(errno));
705 void gmx_parse_gpu_ids(gmx_gpu_opt_t *gpu_opt)
709 if (gpu_opt->gpu_id != NULL && !bGPUBinary)
711 gmx_fatal(FARGS, "GPU ID string set, but %s was compiled without GPU support!", ShortProgram());
714 env = getenv("GMX_GPU_ID");
715 if (env != NULL && gpu_opt->gpu_id != NULL)
717 gmx_fatal(FARGS, "GMX_GPU_ID and -gpu_id can not be used at the same time");
721 env = gpu_opt->gpu_id;
724 /* parse GPU IDs if the user passed any */
727 parse_gpu_id_plain_string(env,
728 &gpu_opt->ncuda_dev_use,
729 &gpu_opt->cuda_dev_use);
731 if (gpu_opt->ncuda_dev_use == 0)
733 gmx_fatal(FARGS, "Empty GPU ID string encountered.\n%s\n",
737 gpu_opt->bUserSet = TRUE;
741 void gmx_select_gpu_ids(FILE *fplog, const t_commrec *cr,
742 const gmx_gpu_info_t *gpu_info,
743 gmx_bool bForceUseGPU,
744 gmx_gpu_opt_t *gpu_opt)
748 char sbuf[STRLEN], stmp[STRLEN];
750 /* Bail if binary is not compiled with GPU acceleration, but this is either
751 * explicitly (-nb gpu) or implicitly (gpu ID passed) requested. */
752 if (bForceUseGPU && !bGPUBinary)
754 gmx_fatal(FARGS, "GPU acceleration requested, but %s was compiled without GPU support!", ShortProgram());
757 if (gpu_opt->bUserSet)
759 /* Check the GPU IDs passed by the user.
760 * (GPU IDs have been parsed by gmx_parse_gpu_ids before)
765 snew(checkres, gpu_opt->ncuda_dev_use);
767 res = check_selected_cuda_gpus(checkres, gpu_info, gpu_opt);
771 print_gpu_detection_stats(fplog, gpu_info, cr);
773 sprintf(sbuf, "Some of the requested GPUs do not exist, behave strangely, or are not compatible:\n");
774 for (i = 0; i < gpu_opt->ncuda_dev_use; i++)
776 if (checkres[i] != egpuCompatible)
778 sprintf(stmp, " GPU #%d: %s\n",
779 gpu_opt->cuda_dev_use[i],
780 gpu_detect_res_str[checkres[i]]);
784 gmx_fatal(FARGS, "%s", sbuf);
791 pick_compatible_gpus(&hwinfo_g->gpu_info, gpu_opt);
793 if (gpu_opt->ncuda_dev_use > cr->nrank_pp_intranode)
795 /* We picked more GPUs than we can use: limit the number.
796 * We print detailed messages about this later in
797 * gmx_check_hw_runconf_consistency.
799 limit_num_gpus_used(gpu_opt, cr->nrank_pp_intranode);
802 gpu_opt->bUserSet = FALSE;
805 /* If the user asked for a GPU, check whether we have a GPU */
806 if (bForceUseGPU && gpu_info->ncuda_dev_compatible == 0)
808 gmx_fatal(FARGS, "GPU acceleration requested, but no compatible GPUs were detected.");
812 static void limit_num_gpus_used(gmx_gpu_opt_t *gpu_opt, int count)
818 ndev_use = gpu_opt->ncuda_dev_use;
820 if (count > ndev_use)
822 /* won't increase the # of GPUs */
829 sprintf(sbuf, "Limiting the number of GPUs to <1 doesn't make sense (detected %d, %d requested)!",
834 /* TODO: improve this implementation: either sort GPUs or remove the weakest here */
835 gpu_opt->ncuda_dev_use = count;
838 void gmx_hardware_info_free(gmx_hw_info_t *hwinfo)
842 ret = tMPI_Thread_mutex_lock(&hw_info_lock);
845 gmx_fatal(FARGS, "Error locking hwinfo mutex: %s", strerror(errno));
848 /* decrease the reference counter */
852 if (hwinfo != hwinfo_g)
854 gmx_incons("hwinfo < hwinfo_g");
859 gmx_incons("n_hwinfo < 0");
864 gmx_cpuid_done(hwinfo_g->cpuid_info);
865 free_gpu_info(&hwinfo_g->gpu_info);
869 ret = tMPI_Thread_mutex_unlock(&hw_info_lock);
872 gmx_fatal(FARGS, "Error unlocking hwinfo mutex: %s", strerror(errno));