Hello Chi-Tuan,
Thanks for following up on this. I was running the example of using genop optimizer in \v8p3r1\notebooks\optim\telemac2d_optim_genop.ipynb. The only thing I changed was in cell 9, the number of processors used by the optimizer.
# run optimization in parallel mode
# ...comments: change parameter nproc depending on your machine
fcost, xopt = mypb.optimize(nproc=2)
I used 2 and it worked fine, but if I use 4 or 8, I got the following errors.
~> Checking keyword/rubrique coherence
~> Checking keyword/rubrique coherence
~> Checking keyword/rubrique coherence
~> Checking keyword/rubrique coherence
~> Checking keyword/rubrique coherence
~> Checking keyword/rubrique coherence
~> Checking keyword/rubrique coherence
~> Checking keyword/rubrique coherence
---------------------------------------------------------------------------
RemoteTraceback Traceback (most recent call last)
RemoteTraceback:
"""
Traceback (most recent call last):
File "/usr/lib/python3.8/multiprocessing/pool.py", line 125, in worker
result = (True, func(*args, **kwds))
File "/usr/lib/python3.8/multiprocessing/pool.py", line 48, in mapstar
return list(map(*args))
File "<ipython-input-4-7e435a25630a>", line 6, in estimation
Fx = study.h_x(CHESTR[0]) # Telemac computation with new friction coefficient
File "/home/qilong/Telemac/v8p3r1/scripts/python3/telapy/tools/study_t2d.py", line 19, in h_x
h, _, _ = self.run_telemac2d(k, finalize=True)
File "/home/qilong/Telemac/v8p3r1/scripts/python3/telapy/tools/study_t2d.py", line 25, in run_telemac2d
self.t2d = Telemac2d(self.studyFiles['t2d.cas'],
File "/home/qilong/Telemac/v8p3r1/scripts/python3/telapy/api/t2d.py", line 58, in __init__
super(Telemac2d, self).__init__("t2d", casfile, user_fortran,
File "/home/qilong/Telemac/v8p3r1/scripts/python3/telapy/api/api_module.py", line 166, in __init__
ctypes.cdll.LoadLibrary(user_fortran_lib_path)
File "/usr/lib/python3.8/ctypes/__init__.py", line 451, in LoadLibrary
return self._dlltype(name)
File "/usr/lib/python3.8/ctypes/__init__.py", line 373, in __init__
self._handle = _dlopen(self._name, mode)
OSError: /home/qilong/Telemac/v8p3r1/examples/telemac2d/estimation/libuser_fortran.so: file too short
"""
The above exception was the direct cause of the following exception:
OSError Traceback (most recent call last)
<ipython-input-9-6e8281fa46e5> in <module>
17 # run optimization in parallel mode
18 # ...comments: change parameter nproc depending on your machine
---> 19 fcost, xopt = mypb.optimize(nproc=8)
~/Telemac/v8p3r1/scripts/python3/telapy/tools/genop/genop.py in optimize(self, nbgen, nproc)
115 self._pop = genpop(self.bounds, self.nvar, self.popsize)
116 # Compute the initial score for the population
--> 117 self._fvalpop, ncalls = cost(self._pop, self.popsize, self.nvar,
118 self.function, nproc)
119 self.nsimul = self.nsimul + ncalls
~/Telemac/v8p3r1/scripts/python3/telapy/tools/genop/costfunction.py in cost(pop, npop, nvar, fname, nproc)
48 else:
49 pool = mp.Pool(processes=nproc)
---> 50 feval = pool.map(fname, pop)
51 pool.close()
52 pool.join()
/usr/lib/python3.8/multiprocessing/pool.py in map(self, func, iterable, chunksize)
362 in a list that is returned.
363 '''
--> 364 return self._map_async(func, iterable, mapstar, chunksize).get()
365
366 def starmap(self, func, iterable, chunksize=None):
/usr/lib/python3.8/multiprocessing/pool.py in get(self, timeout)
769 return self._value
770 else:
--> 771 raise self._value
772
773 def _set(self, i, obj):
OSError: /home/qilong/Telemac/v8p3r1/examples/telemac2d/estimation/libuser_fortran.so: file too short
It seems that libuser_fortran.so was corrupted somehow but I don't know if it's due to the testing environment I was using (gfortran, openmpi and python on Ubuntu 20.04 LTS on WSL2, VS Code as IDE), or it's because multiple processes were trying to overwrite this file.
But if I use 2 processors, it worked as expected.
Kind regards,
Qilong
Assistance 
