nco_bool /* O [flg] File obeys CCM/CCSM/CF conventions */
nco_cnv_ccm_ccsm_cf_inq /* O [fnc] Check if file obeys CCM/CCSM/CF conventions */
(const int nc_id) /* I [id] netCDF file ID */
{
/* Purpose: Check if file adheres to CCM/CCSM/CF history tape format */
nco_bool CNV_CCM_CCSM_CF=False;
char *att_val;
char *cnv_sng=NULL_CEWI;
/* netCDF standard is uppercase Conventions, though some models user lowercase */
char cnv_sng_UC[]="Conventions"; /* Unidata standard string (uppercase) */
char cnv_sng_LC[]="conventions"; /* Unidata non-standard string (lowercase) */
int rcd; /* [rcd] Return code */
long att_sz;
nc_type att_typ;
/* Look for signature of a CCM/CCSM/CF-format file */
cnv_sng=cnv_sng_UC;
rcd=nco_inq_att_flg(nc_id,NC_GLOBAL,cnv_sng,&att_typ,&att_sz);
if(rcd != NC_NOERR){
/* Re-try with lowercase string because some models, e.g., CLM, user lowercase "conventions" */
cnv_sng=cnv_sng_LC;
rcd=nco_inq_att_flg(nc_id,NC_GLOBAL,cnv_sng,&att_typ,&att_sz);
} /* endif lowercase */
if(rcd == NC_NOERR && att_typ == NC_CHAR){
/* Add one for NUL byte */
att_val=(char *)nco_malloc(att_sz*nco_typ_lng(att_typ)+1L);
(void)nco_get_att(nc_id,NC_GLOBAL,cnv_sng,att_val,att_typ);
/* NUL-terminate convention attribute before using strcmp() */
att_val[att_sz]='\0';
/* CCM3, CCSM1 conventions */
if(strstr(att_val,"NCAR-CSM")) CNV_CCM_CCSM_CF=True; /* Backwards compatibility */
/* Climate-Forecast conventions */
if(strstr(att_val,"CF-1.")) CNV_CCM_CCSM_CF=True; /* NB: Not fully implemented TODO nco145 */
/* As of 20060514, CLM 3.0 uses CF1.0 not CF-1.0 (CAM gets it right) */
if(strstr(att_val,"CF1.")) CNV_CCM_CCSM_CF=True; /* NB: Not fully implemented TODO nco145 */
if(CNV_CCM_CCSM_CF && nco_dbg_lvl_get() >= nco_dbg_std){
(void)fprintf(stderr,"%s: CONVENTION File \"%s\" attribute is \"%s\"\n",nco_prg_nm_get(),cnv_sng,att_val);
if(cnv_sng == cnv_sng_LC) (void)fprintf(stderr,"%s: WARNING: This file uses a non-standard attribute (\"%s\") to indicate the netCDF convention. The correct attribute is \"%s\".\n",nco_prg_nm_get(),cnv_sng_LC,cnv_sng_UC);
/* Only warn in arithmetic operators where conventions change behavior */
if(nco_dbg_lvl_get() >= nco_dbg_fl && nco_dbg_lvl_get() != nco_dbg_dev && nco_is_rth_opr(nco_prg_id_get())) (void)fprintf(stderr,"%s: INFO NCO attempts to abide by many official and unofficial metadata conventions including ARM, CCM, CCSM, and CF. To adhere to these conventions, NCO implements variable-specific exceptions in certain operators, e.g., ncbo will not subtract variables named \"date\" or \"gw\", and many operators will always leave coordinate variables unchanged. The full list of exceptions is in the manual http://nco.sf.net/nco.html#CF\n",nco_prg_nm_get());
} /* endif dbg */
att_val=(char *)nco_free(att_val);
} /* endif */
return CNV_CCM_CCSM_CF;
} /* end nco_cnv_ccm_ccsm_cf_inq */
int /* O [nbr] Thread number */
nco_openmp_ini /* [fnc] Initialize OpenMP threading environment */
(const int thr_nbr) /* I [nbr] User-requested thread number */
{
/* Purpose: Initialize OpenMP multi-threading environment
Honor user-requested thread number, balance against known code efficiency,
print diagnostics
Returns thr_nbr=1 in three situations:
1. UP codes (not threaded)
2. SMP codes compiled with compilers which lack OpenMP support
3. SMP codes where single thread requested/advised
Otherwise returns system-dependent thr_nbr */
/* Using naked stdin/stdout/stderr in parallel region generates warning
Copy appropriate filehandle to variable scoped shared in parallel clause */
char *nvr_OMP_NUM_THREADS; /* [sng] Environment variable OMP_NUM_THREADS */
char *sng_cnv_rcd=NULL_CEWI; /* [sng] strtol()/strtoul() return code */
FILE * const fp_stderr=stderr; /* [fl] stderr filehandle CEWI */
nco_bool USR_SPC_THR_RQS=False;
int dyn_thr=1; /* [flg] Allow system to dynamically set number of threads */
int ntg_OMP_NUM_THREADS=int_CEWI; // [nbr] OMP_NUM_THREADS environment variable
int prc_nbr_max; /* [nbr] Maximum number of processors available */
int thr_nbr_act; /* O [nbr] Number of threads NCO uses */
int thr_nbr_max_fsh=4; /* [nbr] Maximum number of threads program can use efficiently */
int thr_nbr_max=int_CEWI; /* [nbr] Maximum number of threads system allows */
int thr_nbr_rqs=int_CEWI; /* [nbr] Number of threads to request */
#ifndef _OPENMP
if(nco_dbg_lvl_get() >= nco_dbg_std) (void)fprintf(fp_stderr,"%s: INFO Build compiler lacked (or user turned off) OpenMP support. Code will execute with single thread in Uni-Processor (UP) mode.\n",nco_prg_nm_get());
return (int)1;
#endif /* !_OPENMP */
/* Strategy:
0. Determine maximum number of threads system will allocate (thr_nbr_max)
1. Command-line thread request, if any, overrides automatic algorithm
2. If no command-line request then system allocates OMP_NUM_THREADS if possible
3. Reduce maximum number of threads available to system to thr_nbr_max_fsh
Many operators cannot use more than thr_nbr_max_fsh ~ 2--4 threads efficiently
Play nice: Set dynamic threading so that system can make efficiency decisions
When dynamic threads are set, system never allocates more than thr_nbr_max_fsh */
if(thr_nbr < 0){
(void)fprintf(fp_stderr,"%s: ERROR User-requested thread number = %d is less than zero\n",nco_prg_nm_get(),thr_nbr);
nco_exit(EXIT_FAILURE);
} /* endif err */
if(thr_nbr == 0)
if(nco_dbg_lvl_get() >= nco_dbg_scl && nco_dbg_lvl_get() != nco_dbg_dev )
(void)fprintf(fp_stderr,"%s: INFO User did not specify thread request > 0 on command line. NCO will automatically assign threads based on OMP_NUM_THREADS environment and machine capabilities.\nHINT: Not specifiying any --thr_nbr (or specifying --thr_nbr=0) causes NCO to try to pick the optimal thread number. Specifying --thr_nbr=1 tells NCO to execute in Uni-Processor (UP) (i.e., single-threaded) mode.\n",nco_prg_nm_get());
if(thr_nbr > 0) USR_SPC_THR_RQS=True;
prc_nbr_max=omp_get_num_procs(); /* [nbr] Maximum number of processors available */
if(omp_in_parallel()){
(void)fprintf(fp_stderr,"%s: ERROR Attempted to get maximum thread number from within parallel region\n",nco_prg_nm_get());
nco_exit(EXIT_FAILURE);
}else{
thr_nbr_max=omp_get_max_threads(); /* [nbr] Maximum number of threads system allows */
} /* end error */
if(nco_dbg_lvl_get() >= nco_dbg_scl && nco_dbg_lvl_get() != nco_dbg_dev){
if((nvr_OMP_NUM_THREADS=getenv("OMP_NUM_THREADS"))) ntg_OMP_NUM_THREADS=(int)strtol(nvr_OMP_NUM_THREADS,&sng_cnv_rcd,NCO_SNG_CNV_BASE10); /* [sng] Environment variable OMP_NUM_THREADS */
if(nvr_OMP_NUM_THREADS && *sng_cnv_rcd) nco_sng_cnv_err(nvr_OMP_NUM_THREADS,"strtol",sng_cnv_rcd);
(void)fprintf(fp_stderr,"%s: INFO Environment variable OMP_NUM_THREADS ",nco_prg_nm_get());
if(ntg_OMP_NUM_THREADS > 0) (void)fprintf(fp_stderr,"= %d\n",ntg_OMP_NUM_THREADS); else (void)fprintf(fp_stderr,"does not exist\n");
(void)fprintf(fp_stderr,"%s: INFO omp_get_num_procs() reports number of processors available is %d\n",nco_prg_nm_get(),prc_nbr_max);
(void)fprintf(fp_stderr,"%s: INFO omp_get_max_threads() reports maximum number of threads system allows is %d\n",nco_prg_nm_get(),thr_nbr_max);
} /* endif dbg */
if(USR_SPC_THR_RQS){
/* Try to honor user-specified thread request... */
thr_nbr_rqs=thr_nbr; /* [nbr] Number of threads to request */
/* ...if possible... */
if(nco_dbg_lvl_get() >= nco_dbg_scl) (void)fprintf(fp_stderr,"%s: INFO Command-line requests %d thread%s\n",nco_prg_nm_get(),thr_nbr,(thr_nbr > 1) ? "s" : "");
if(thr_nbr > thr_nbr_max){
(void)fprintf(fp_stderr,"%s: WARNING Reducing user-requested thread number = %d to maximum thread number allowed = %d\n",nco_prg_nm_get(),thr_nbr,thr_nbr_max);
thr_nbr_rqs=thr_nbr_max; /* [nbr] Number of threads to request */
} /* endif */
}else{ /* !USR_SPC_THR_RQS */
/* Otherwise use automatic thread allocation algorithm */
/* Request maximum number of threads permitted */
thr_nbr_rqs=thr_nbr_max; /* [nbr] Number of threads to request */
/* Restrict threading on per-program basis to play nicely with others */
switch(nco_prg_id_get()){
/* Operators with pre-set thread limit
NB: All operators currently have default restrictions
2007: Only ncwa and ncap2 have a chance to scale on non-parallel filesystems
ncap2 may, one day, see a big performance boost from threading
However, as of 20090327, ncap2 threading may be buggy due to ANTLR
Moreover, we want to prevent hogging processes on 32-way nodes
until/unless clear benefits of threading are demonstrated.
2015: Threads improve ncks regridding performance by 2-3x on ACME ~1-20 GB netCDF3 files */
case ncap:
/* 20090327: Restrict ncap2 to one thread until ANTLR threading resolved */
thr_nbr_max_fsh=1;
break;
case ncecat:
case ncrcat:
/* ncecat and ncrcat are extremely I/O intensive
Maximum efficiency when one thread reads from input file while other writes to output file */
// 20140219: Turn-off OpenMP until thoroughly tested
// thr_nbr_max_fsh=2;
thr_nbr_max_fsh=1;
break;
case ncks:
// 20150529: Turn-on OpenMP for regridder
thr_nbr_max_fsh=16;
break;
case ncwa:
// 20150530: Turn-on OpenMP for debugging
// 20150610: Eight threads with ncwa seemed to work for a little while, then it got flaky. Turned-off for 4.5.0 release
// 20150622: Allowing eight threads again for debugging with -D 3
// 20150701: Firmly established that netCDF4 involvement hoses threading because HDF5 is not threadsafe by default
// 20150710: Turned-off for 4.5.1 release
// Symptoms of bugs, if any, show up with
// cd ~/nco/bm;nco_bm.pl --regress ncwa;cd -
thr_nbr_max_fsh=1;
if(nco_dbg_lvl_get() >= nco_dbg_scl) thr_nbr_max_fsh=1;
break;
/* Operators with higher maximum pre-set thread limit (NB: not all of these are threaded!) */
case ncra:
thr_nbr_max_fsh=1;
if(nco_dbg_lvl_get() >= nco_dbg_scl) thr_nbr_max_fsh=1;
break;
case ncbo:
case ncatted:
case ncfe:
case ncflint:
case ncpdq:
case ncrename:
case ncge:
// 20140219: Turn-off OpenMP until thoroughly tested
// thr_nbr_max_fsh=4;
thr_nbr_max_fsh=1;
break;
default: nco_dfl_case_prg_id_err(); break;
} /* end case */
/* Automatic algorithm tries to play nice with others */
(void)omp_set_dynamic(dyn_thr); /* [flg] Allow system to dynamically set number of threads */
if(nco_dbg_lvl_get() >= nco_dbg_std) (void)fprintf(fp_stderr,"%s: INFO omp_set_dynamic() used to %s OS to dynamically set threads\n",nco_prg_nm_get(),(dyn_thr ? "ALLOW" : "DISALLOW"));
dyn_thr=omp_get_dynamic(); /* [flg] Allow system to dynamically set number of threads */
if(nco_dbg_lvl_get() >= nco_dbg_std) (void)fprintf(fp_stderr,"%s: INFO omp_get_dynamic() reports system will%s utilize dynamic threading\n",nco_prg_nm_get(),(dyn_thr ? "" : " NOT"));
/* Apply program/system limitations */
if(thr_nbr_max > thr_nbr_max_fsh){
if(nco_dbg_lvl_get() >= nco_dbg_std) (void)fprintf(fp_stderr,"%s: INFO Reducing default thread number from %d to %d, an operator-dependent \"play-nice\" number set in nco_openmp_ini()\n",nco_prg_nm_get(),thr_nbr_max,thr_nbr_max_fsh);
thr_nbr_rqs=thr_nbr_max_fsh; /* [nbr] Number of threads to request */
} /* endif */
} /* !USR_SPC_THR_RQS */
#ifdef ENABLE_NETCDF4
if(nco_prg_id_get() != ncks && nco_prg_id_get() != ncwa && nco_prg_id_get() != ncra && thr_nbr_rqs > 1){
if(USR_SPC_THR_RQS && nco_dbg_lvl_get() >= nco_dbg_fl) (void)fprintf(stdout,"%s: WARNING This is TODO nco939. Requested threading with netCDF4 (HDF5) support. The NCO thread request algorithm considers user-input, environment variables, and software and hardware limitations in determining the number of threads to request, thr_nbr_rqs. At this point NCO would request result %d threads from a netCDF3-based library. However, this NCO was built with netCDF4, which relies on HDF5. netCDF4 is not thread-safe unless HDF5 is configured with the (non-default) --enable-threadsafe option. NCO currently has no way to know whether HDF5 was built thread-safe. Hence, all netCDF4-based operators are currently restricted to a single thread. The program will now automatically set thr_nbr_rqs = 1.\nThis unfortunate limitation is necessary to keep the NCO developers sane. If you want/need threading in netCDF4-based NCO, please politely yet firmly request of the Unidata netCDF developers that better thread support be built into netCDF4, and request of the HDF5 developers that they make the --enable-threadsafe option compatible with all HDF5 libraries and APIs, including Fortran (which, as of HDF5 1.8.0 in 2008, is incompatible with --enable-threadsafe).\n",nco_prg_nm_get(),thr_nbr_rqs);
thr_nbr_rqs=1;
} /* endif */
#endif /* !ENABLE_NETCDF4 */
/* Set thread number */
if(omp_in_parallel()){
(void)fprintf(fp_stderr,"%s: ERROR Attempted to set thread number from within parallel region\n",nco_prg_nm_get());
nco_exit(EXIT_FAILURE);
}else{
(void)omp_set_num_threads(thr_nbr_rqs);
if(nco_dbg_lvl_get() >= nco_dbg_std) (void)fprintf(fp_stderr,"%s: INFO omp_set_num_threads() used to set execution environment to spawn teams of %d thread(s)\n",nco_prg_nm_get(),thr_nbr_rqs);
} /* end error */
thr_nbr_act=omp_get_max_threads();
if(nco_dbg_lvl_get() >= nco_dbg_scl) (void)fprintf(fp_stderr,"%s: INFO After using omp_set_num_threads() to adjust for any user requests/NCO optimizations, omp_get_max_threads() reports that a parallel construct here/now would spawn %d thread(s)\n",nco_prg_nm_get(),thr_nbr_act);
#ifdef _OPENMP
if(nco_dbg_lvl_get() >= nco_dbg_scl){
# pragma omp parallel default(none) shared(thr_nbr_act)
{ /* begin OpenMP parallel */
# pragma omp single nowait
{ /* begin OpenMP single */
thr_nbr_act=omp_get_num_threads(); /* [nbr] Number of threads NCO uses */
if(nco_dbg_lvl_get() >= nco_dbg_std) (void)fprintf(fp_stderr,"%s: INFO Small parallel test region spawned team of %d thread(s)\n",nco_prg_nm_get(),thr_nbr_act);
} /* end OpenMP single */
} /* end OpenMP parallel */
} /* end dbg */
#endif /* !_OPENMP */
/* Issue any warnings about OpenMP credibility during debugging phase */
if(True)
if((nco_prg_id_get() == ncwa || nco_prg_id_get() == ncra) && thr_nbr_act > 1)
if(nco_dbg_lvl_get() >= nco_dbg_std) (void)fprintf(fp_stderr,"%s: WARNING OpenMP threading active with %d threads but not guaranteed to work on this operator. If strange behavior (e.g., NaN results) ensues, manually turn-off multi-threading by specifying \"-t 1\" option.\n",nco_prg_nm_get(),thr_nbr_act);
return thr_nbr_act; /* O [nbr] Number of threads NCO uses */
} /* end nco_openmp_ini() */
