Some control over the launched threads in scatsystem.

Former-commit-id: a67102dcb367b8fe577f9d8896c9a477571c7d6f

misc/201903_finiterectlat_AaroBEC_Mie.py

@@ -1,12 +1,17 @@
 #!/usr/bin/env python3
 # coding: utf-8
-from qpms import Particle, CTMatrix, BaseSpec, FinitePointGroup, ScatteringSystem, TMatrixInterpolator, eV, hbar, c, MaterialInterpolator
+from qpms import Particle, CTMatrix, BaseSpec, FinitePointGroup, ScatteringSystem, TMatrixInterpolator, eV, hbar, c, MaterialInterpolator, scatsystem_set_nthreads
 from qpms.symmetries import point_group_info
 import numpy as np
 import os
 import sys
 nm = 1e-9
 
+
+if 'SLURM_CPUS_PER_TASK' in os.environ:
+        scatsystem_set_nthreads(os.environ['SLURM_CPUS_PER_TASK'])
+
+
 rewrite_output = '--rewrite-output' in sys.argv
 
 cyr_part_height = 50*nm

misc/201903_finiterectlat_AaroBEC_fatMie.py

@@ -1,10 +1,14 @@
 #!/usr/bin/env python3
 # coding: utf-8
-from qpms import Particle, CTMatrix, BaseSpec, FinitePointGroup, ScatteringSystem, TMatrixInterpolator, eV, hbar, c, MaterialInterpolator
+from qpms import Particle, CTMatrix, BaseSpec, FinitePointGroup, ScatteringSystem, TMatrixInterpolator, eV, hbar, c, MaterialInterpolator, scatsystem_set_nthreads
 from qpms.symmetries import point_group_info
 import numpy as np
 import os
 import sys
+
+if 'SLURM_CPUS_PER_TASK' in os.environ:
+    scatsystem_set_nthreads(os.environ['SLURM_CPUS_PER_TASK'])
+
 nm = 1e-9
 
 rewrite_output = '--rewrite-output' in sys.argv

qpms/qpms_c.pyx

@@ -1398,6 +1398,10 @@ cdef class Particle:
             else:
                 raise ValueError("Position argument has to contain 3 or 2 cartesian coordinates")
 
+cpdef void scatsystem_set_nthreads(long n):
+    qpms_scatsystem_set_nthreads(n)
+    return
+
 cdef class ScatteringSystem:
     '''
     Wrapper over the C qpms_scatsys_t structure.

qpms/qpms_cdefs.pxd

@@ -290,6 +290,7 @@ cdef extern from "tmatrices.h":
 
 
 cdef extern from "scatsystem.h":
+    void qpms_scatsystem_set_nthreads(long n)
     struct qpms_particle_t:
         cart3_t pos
         const qpms_tmatrix_t *tmatrix

qpms/scatsystem.c

@@ -22,6 +22,11 @@
 #define QPMS_SCATSYS_TMATRIX_RTOL 1e-12
 
 long qpms_scatsystem_nthreads_default = 4;
+long qpms_scatsystem_nthreads_override = 0;
+
+void qpms_scatsystem_set_nthreads(long n) {
+  qpms_scatsystem_nthreads_override = n;
+}
 
 // ------------ Stupid implementation of qpms_scatsys_apply_symmetry() -------------
 
@@ -1419,7 +1424,13 @@ complex double *qpms_scatsys_build_modeproblem_matrix_irrep_packed_parallelR(
     arg = {ss, &opistartR, &opistartR_mutex, iri, target_packed, k};
 
   // FIXME THIS IS NOT PORTABLE:
-  long nthreads = sysconf(_SC_NPROCESSORS_ONLN);
+  long nthreads;
+  if (qpms_scatsystem_nthreads_override > 0) {
+    nthreads = qpms_scatsystem_nthreads_override;
+    QPMS_WARN("Using overriding value of %ld thread(s).", 
+        nthreads);
+  } else {
+    nthreads = sysconf(_SC_NPROCESSORS_ONLN);
     if (nthreads < 1) {
       QPMS_WARN("_SC_NPROCESSORS_ONLN returned %ld, using %ld thread(s) instead.",
          nthreads, qpms_scatsystem_nthreads_default);
@@ -1427,6 +1438,7 @@ complex double *qpms_scatsys_build_modeproblem_matrix_irrep_packed_parallelR(
     } else {
       QPMS_DEBUG("_SC_NRPOCESSORS_ONLN returned %ld.", nthreads);
     }
+  }
   pthread_t thread_ids[nthreads];
   for(long thi = 0; thi < nthreads; ++thi)
     QPMS_ENSURE_SUCCESS(pthread_create(thread_ids + thi, NULL,

qpms/scatsystem.h

@@ -13,6 +13,11 @@
 #include "qpms_types.h"
 #include <stdbool.h>
 
+
+/// Overrides the number of threads spawned by the paralellized functions.
+/** TODO MORE DOC which are those? */
+void qpms_scatsystem_set_nthreads(long n);
+
 /// A particle, defined by its T-matrix and position.
 typedef struct qpms_particle_t {
 	// Does it make sense to ever use other than cartesian coords for this?