Some confusion about the example "Simulated BBH example"

[SDYZZY]

Hi, I am new to PyCBC and I'm trying to learn how to use PyCBC from the tutorials. Everything went well until I encountered a problem while running the example called "Simulated BBH example" from the PyCBC inference documentation (pycbc.inference). Here are the steps I followed:

Firstly, I downloaded the file injection.ini and executed the script make_injection.sh from the webpage mentioned above. After completing these steps, I obtained the file injection.hdf.

Secondly, I downloaded the files gw150914_like.ini, data.ini, emcee_pt-gw150914_like.ini and run.sh in turn.

Then, I executed the script run.sh on a cluster with 1 node and 10 cores, as described in the example. The documentation mentioned that:

In the example, we have set the parallelization to use 10 cores. With these settings, it should checkpoint approximately every hour or two. The run should complete in a few hours.

It seems easy to repeat this example. However, after running for 48 hours, I didn't receive any output except for the files inference.hdf.bkup and inference.hdf.checkpoint. According to my understanding, I will get a file named inference.hdf if the script ran successfully, just like when I ran another example called "GW150914 example with gaussian noise model" in my environment before attempting this one.

I have been troubled by this problem for almost a month, and I even reinstalled PyCBC last week using the method described in "Full Virtualenv for Development and Production", but nothing changed (I used pip install pycbc and conda install -c conde-forge pycbc before). I don't know if there are something wrong in my steps, or if I forget some configuration, or this example needs more time to finish?

Any assistance or guidance would be extremely appreciated!

[SDYZZY]

Here are the packages installed after I reinstalled PyCBC using the method described in "Full Virtualenv for Development and Production"

(pycbc_tutorial) [sdyzzy@login02 ~]$ pip list
Package                            Version   Editable project location
---------------------------------- --------- ------------------------------------------
addict                             2.4.0
alabaster                          0.7.12
anaconda-client                    1.7.2
anaconda-navigator                 1.9.7
anaconda-project                   0.8.3
appdirs                            1.4.4
archspec                           0.1.1
ase                                3.20.1
asn1crypto                         1.0.1
astroid                            2.3.1
astroplan                          0.9.1
astropy                            4.3.1
astropy-healpix                    0.7
astunparse                         1.6.3
atomicwrites                       1.3.0
attrs                              19.2.0
awkde                              0.1
Babel                              2.12.1
backcall                           0.1.0
backports.functools-lru-cache      1.5
backports.os                       0.1.1
backports.shutil-get-terminal-size 1.0.0
backports.tempfile                 1.0
backports.weakref                  1.0.post1
bcrypt                             4.0.1
beartype                           0.10.0
beautifulsoup4                     4.8.0
bitarray                           1.0.1
bkcharts                           0.2
bleach                             3.1.0
blessings                          1.7
bokeh                              1.3.4
boto                               2.49.0
Bottleneck                         1.2.1
bracex                             2.3.post1
certifi                            2019.9.11
cffi                               1.12.3
cftime                             1.6.2
chardet                            3.0.4
charset-normalizer                 2.1.1
Click                              7.0
cloudpickle                        1.2.2
clyent                             1.2.2
colorama                           0.4.1
colored                            1.4.3
conda                              4.8.5
conda-build                        3.18.9
conda-package-handling             1.6.0
conda-verify                       3.4.2
contextlib2                        0.6.0
corner                             2.2.1
cpnest                             0.11.5
cryptography                       2.7
cupy                               6.0.0
custodian                          2022.5.26
cycler                             0.10.0
Cython                             0.29.13
cytoolz                            0.10.0
dargs                              0.3.3
dask                               2.5.2
decorator                          4.4.0
defusedxml                         0.6.0
distributed                        2.5.2
docutils                           0.15.2
dpdata                             0.2.10
dpdispatcher                       0.4.19
dpgen                              0.10.6
dqsegdb2                           1.2.1
dynesty                            2.1.2
emcee                              2.2.1
entrypoints                        0.3
epsie                              1.0.0
et-xmlfile                         1.0.1
fastcache                          1.1.0
fastrlock                          0.5
filelock                           3.0.12
Flask                              1.1.1
fonttools                          4.38.0
fsspec                             0.5.2
future                             0.17.1
gevent                             1.4.0
gitdb                              4.0.10
GitPython                          3.1.36
Glances                            3.2.5
glob2                              0.7
gmpy2                              2.0.8
gpaw                               20.10.0   /opt/anaconda3/lib/python3.7/site-packages
gpustat                            0.6.0
greenlet                           0.4.15
GromacsWrapper                     0.8.2
gwdatafind                         1.1.3
gwosc                              0.7.1
gwpy                               3.0.5
h5py                               3.8.0
healpy                             1.16.2
HeapDict                           1.0.1
html5lib                           1.0.1
humanfriendly                      10.0
humanize                           4.0.0
idna                               2.8
igwn-auth-utils                    1.0.2
imageio                            2.6.0
imagesize                          1.4.1
importlib-metadata                 5.0.0
ipykernel                          5.1.2
ipython                            7.8.0
ipython_genutils                   0.2.0
ipywidgets                         7.5.1
isort                              4.3.21
itsdangerous                       1.1.0
jdcal                              1.4.1
jedi                               0.15.1
jeepney                            0.4.1
Jinja2                             3.1.2
joblib                             0.13.2
json5                              0.8.5
jsonschema                         3.0.2
jupyter                            1.0.0
jupyter-client                     5.3.3
jupyter-console                    6.0.0
jupyter-core                       4.5.0
jupyterlab                         1.1.4
jupyterlab-server                  1.0.6
jupyterlab-widgets                 3.0.3
kaleido                            0.2.1
keyring                            18.0.0
kiwisolver                         1.1.0
lalsuite                           7.5
lazy-object-proxy                  1.4.2
libarchive-c                       2.8
lief                               0.9.0
ligo-gracedb                       2.12.0
ligo-segments                      1.4.0
ligo.skymap                        0.5.3
ligotimegps                        2.0.1
llvmlite                           0.29.0
locket                             0.2.0
lscsoft-glue                       3.0.1
lxml                               4.4.1
Mako                               1.1.3
MarkupSafe                         2.0.1
matplotlib                         3.5.3
mccabe                             0.6.1
mdtraj                             1.9.7
mistune                            0.8.4
mkl-fft                            1.0.14
mkl-random                         1.1.0
mkl-service                        2.3.0
mock                               3.0.5
monty                              2022.9.9
more-itertools                     7.2.0
mpi4py                             3.0.3
mpld3                              0.5.9
mpmath                             1.1.0
mrcfile                            1.4.3
msgpack                            0.6.1
multipledispatch                   0.6.0
navigator-updater                  0.2.1
nbconvert                          5.6.0
nbformat                           4.4.0
netCDF4                            1.6.1
networkx                           2.3
nglview                            3.0.3
nltk                               3.4.5
nose                               1.3.7
notebook                           6.0.1
numba                              0.45.1
numexpr                            2.7.0
numkit                             1.2.2
numpy                              1.21.6
numpydoc                           0.9.1
nvidia-ml-py3                      7.352.0
olefile                            0.46
openpyxl                           3.0.0
packaging                          23.1
palettable                         3.3.0
pandas                             1.3.5
pandocfilters                      1.4.2
paramiko                           2.12.0
parse                              1.19.0
parso                              0.5.1
partd                              1.0.0
path.py                            12.0.1
pathlib2                           2.3.5
patsy                              0.5.1
pegasus-wms.api                    5.0.6
pegasus-wms.common                 5.0.6
pep8                               1.7.1
pexpect                            4.7.0
phonopy                            2.5.0
pickleshare                        0.7.5
Pillow                             6.2.0
pip                                23.2.1
pkginfo                            1.5.0.1
plotly                             5.10.0
pluggy                             0.13.0
ply                                3.11
prometheus-client                  0.7.1
prompt-toolkit                     2.0.10
psutil                             5.6.3
ptemcee                            1.0.0
ptyprocess                         0.6.0
py                                 1.8.0
py3nvml                            0.2.7
py4vasp                            0.4.0
pybind11                           2.11.1
PyCBC                              0.0a8707
pycodestyle                        2.5.0
pycosat                            0.6.3
pycparser                          2.19
pycrypto                           2.6.1
pycuda                             2019.1.2
pycurl                             7.43.0.3
pyerfa                             2.0.0.3
pyflakes                           2.1.1
Pygments                           2.16.1
PyJWT                              2.8.0
pykerr                             0.1.0
pylint                             2.4.2
pymatgen                           2022.0.17
pymultinest                        2.12
PyNaCl                             1.5.0
pyodbc                             4.0.27
pyOpenSSL                          19.0.0
pyparsing                          2.4.2
PyQt5                              5.12.3
PyQt5-sip                          12.12.2
PyQtWebEngine                      5.12.1
pyrsistent                         0.15.4
pyRXP                              3.0.1
PySocks                            1.7.1
pytest                             5.2.1
pytest-arraydiff                   0.3
pytest-astropy                     0.5.0
pytest-doctestplus                 0.4.0
pytest-openfiles                   0.4.0
pytest-remotedata                  0.3.2
python-dateutil                    2.8.0
python-ligo-lw                     1.8.3
pytools                            2020.3
pytz                               2019.3
PyWavelets                         1.0.3
PyYAML                             6.0.1
pyzmq                              18.1.0
QtAwesome                          0.6.0
qtconsole                          4.5.5
QtPy                               1.9.0
reproject                          0.8
requests                           2.28.1
rope                               0.14.0
ruamel_yaml                        0.15.46
safe-netrc                         1.0.1
scikit-image                       0.15.0
scikit-learn                       0.21.3
scipy                              1.7.3
scitokens                          1.8.1
seaborn                            0.9.0
SecretStorage                      3.1.1
Send2Trash                         1.5.0
sentry-sdk                         1.10.1
setproctitle                       1.3.2
setuptools                         68.0.0
simplegeneric                      0.8.1
singledispatch                     3.4.0.3
six                                1.12.0
slurm-gpustat                      0.0.12
smmap                              5.0.1
snowballstemmer                    2.0.0
sortedcollections                  1.1.2
sortedcontainers                   2.1.0
soupsieve                          1.9.3
spglib                             1.16.0
Sphinx                             5.3.0
sphinx-carousel                    1.2.0
sphinx_design                      0.4.1
sphinx-rtd-theme                   1.3.0
sphinxcontrib-applehelp            1.0.1
sphinxcontrib-devhelp              1.0.1
sphinxcontrib-htmlhelp             2.0.0
sphinxcontrib-jquery               4.1
sphinxcontrib-jsmath               1.0.1
sphinxcontrib-programoutput        0.17
sphinxcontrib-qthelp               1.0.2
sphinxcontrib-serializinghtml      1.1.5
sphinxcontrib-websupport           1.1.2
spyder                             3.3.6
spyder-kernels                     0.5.2
SQLAlchemy                         1.3.9
statsmodels                        0.10.1
sympy                              1.10.1
tables                             3.5.2
tabulate                           0.9.0
tblib                              1.4.0
tenacity                           8.1.0
terminado                          0.8.2
testpath                           0.4.2
toolz                              0.10.0
torch                              1.3.1
tornado                            6.0.3
tqdm                               4.36.1
traitlets                          4.3.3
typing_extensions                  4.4.0
ultranest                          3.6.2
uncertainties                      3.1.7
unicodecsv                         0.14.1
urllib3                            1.26.12
wcmatch                            8.4.1
wcwidth                            0.1.7
webencodings                       0.5.1
Werkzeug                           0.16.0
wheel                              0.33.6
widgetsnbextension                 3.5.1
wrapt                              1.11.2
wurlitzer                          1.0.3
xlrd                               1.2.0
XlsxWriter                         1.2.1
xlwt                               1.3.0
xmltodict                          0.13.0
yt                                 3.4.1
zict                               1.0.0
zipp                               0.6.0

And here is the output I got after 36 hours' running.

Directory is /gpfs/home/phys/sdyzzy/2023autumn/pycbc_tutorial/Simulated_BBH_example
This job runs on the following nodes:
cnode266
This job has allocated 10 cpu cores.
Loading config file
Reading configuration file
Reading distributions
Drawing samples
Writing results
Using seed 12
Running with CPU support: 1 threads
Reading configuration file
Setting up model
Setting up priors for each parameter
Sampling in mchirp, q in place of mass1, mass2
Loading waveform transforms
Determining analysis times to use
Padding H1 analysis start and end times by 4 (= psd-inverse-length/2) seconds to account for PSD wrap around effects.
Padding L1 analysis start and end times by 4 (= psd-inverse-length/2) seconds to account for PSD wrap around effects.
Generating Fake Strain
Making PSD for strain
Making colored noise
Highpass Filtering
Resampling data
Applying injections
Injecting at 1126259462.42, method is lal
Converting to float64
Highpass Filtering
Remove Padding
Generating Fake Strain
Making PSD for strain
Making colored noise
Highpass Filtering
Resampling data
Applying injections
Injecting at 1126259462.42, method is lal
Converting to float64
Highpass Filtering
Remove Padding
Will generate a different time series for PSD estimation
Generating Fake Strain
Making PSD for strain
Making colored noise
Highpass Filtering
Resampling data
Applying injections
Injecting at 1126259462.42, method is lal
Converting to float64
Highpass Filtering
Remove Padding
Generating Fake Strain
Making PSD for strain
Making colored noise
Highpass Filtering
Resampling data
Applying injections
Injecting at 1126259462.42, method is lal
Converting to float64
Highpass Filtering
Remove Padding
Applying gates to PSD data
WARNING: The following parameters are generally not used by CBC waveform generators: spin1_polar, spin1_a, spin2_a, spin1_azimuthal, delta_tc, trigger_time, spin2_azimuthal, spin2_polar. If you have provided a transform that converted these into known parameters (e.g., mchirp, q to mass1, mass2) or you are using a custom model that uses these parameters, you can safely ignore this message.
Setting up sampler
Setting max samples per chain to 1000
Looking for checkpoint file
Checkpoint not found or not valid
Creating file inference.hdf.checkpoint
Writing injection file to output
Running sampler for 0 to 2000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 4
Writing samples to inference.hdf.bkup with thin interval 4
Updating burn in
Evaluating nacl burn-in test
ACT: 148.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 2000 to 4000 iterations
Thinning samples in inference.hdf.checkpoint by a factor of 8
Writing samples to inference.hdf.checkpoint with thin interval 8
Thinning samples in inference.hdf.bkup by a factor of 8
Writing samples to inference.hdf.bkup with thin interval 8
Updating burn in
Evaluating nacl burn-in test
ACT: 296.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 4000 to 6000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 8
Writing samples to inference.hdf.bkup with thin interval 8
Updating burn in
Evaluating nacl burn-in test
ACT: 448.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 6000 to 8000 iterations
Thinning samples in inference.hdf.checkpoint by a factor of 16
Writing samples to inference.hdf.checkpoint with thin interval 16
Thinning samples in inference.hdf.bkup by a factor of 16
Writing samples to inference.hdf.bkup with thin interval 16
Updating burn in
Evaluating nacl burn-in test
ACT: 592.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 8000 to 10000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 16
Writing samples to inference.hdf.bkup with thin interval 16
Updating burn in
Evaluating nacl burn-in test
ACT: 736.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 10000 to 12000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 16
Writing samples to inference.hdf.bkup with thin interval 16
Updating burn in
Evaluating nacl burn-in test
ACT: 880.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 12000 to 14000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 16
Writing samples to inference.hdf.bkup with thin interval 16
Updating burn in
Evaluating nacl burn-in test
ACT: 1040.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 14000 to 16000 iterations
Thinning samples in inference.hdf.checkpoint by a factor of 32
Writing samples to inference.hdf.checkpoint with thin interval 32
Thinning samples in inference.hdf.bkup by a factor of 32
Writing samples to inference.hdf.bkup with thin interval 32
Updating burn in
Evaluating nacl burn-in test
ACT: 1184.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 16000 to 18000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 32
Writing samples to inference.hdf.bkup with thin interval 32
Updating burn in
Evaluating nacl burn-in test
ACT: 1344.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 18000 to 20000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 32
Writing samples to inference.hdf.bkup with thin interval 32
Updating burn in
Evaluating nacl burn-in test
ACT: 1472.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 20000 to 22000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 32
Writing samples to inference.hdf.bkup with thin interval 32
Updating burn in
Evaluating nacl burn-in test
ACT: 1632.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 22000 to 24000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 32
Writing samples to inference.hdf.bkup with thin interval 32
Updating burn in
Evaluating nacl burn-in test
ACT: 1760.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 24000 to 26000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 32
Writing samples to inference.hdf.bkup with thin interval 32
Updating burn in
Evaluating nacl burn-in test
ACT: 1952.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 26000 to 28000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 32
Writing samples to inference.hdf.bkup with thin interval 32
Updating burn in
Evaluating nacl burn-in test
ACT: 2080.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 28000 to 30000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 32
Writing samples to inference.hdf.bkup with thin interval 32
Updating burn in
Evaluating nacl burn-in test
ACT: 2208.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 30000 to 32000 iterations
Thinning samples in inference.hdf.checkpoint by a factor of 64
Writing samples to inference.hdf.checkpoint with thin interval 64
Thinning samples in inference.hdf.bkup by a factor of 64
Writing samples to inference.hdf.bkup with thin interval 64
Updating burn in
Evaluating nacl burn-in test
ACT: 2368.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 32000 to 34000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 64
Writing samples to inference.hdf.bkup with thin interval 64
Updating burn in
Evaluating nacl burn-in test
ACT: 2560.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 34000 to 36000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 64
Writing samples to inference.hdf.bkup with thin interval 64
Updating burn in
Evaluating nacl burn-in test
ACT: 2688.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 36000 to 38000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 64
Writing samples to inference.hdf.bkup with thin interval 64
Updating burn in
Evaluating nacl burn-in test
ACT: 2816.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 38000 to 40000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 64
Writing samples to inference.hdf.bkup with thin interval 64
Updating burn in
Evaluating nacl burn-in test
ACT: 2944.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 40000 to 42000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 64
Writing samples to inference.hdf.bkup with thin interval 64
Updating burn in
Evaluating nacl burn-in test
ACT: 3136.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 42000 to 44000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 64
Writing samples to inference.hdf.bkup with thin interval 64
Updating burn in
Evaluating nacl burn-in test
ACT: 3264.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 44000 to 46000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 64
Writing samples to inference.hdf.bkup with thin interval 64
Updating burn in
Evaluating nacl burn-in test
ACT: 3392.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 46000 to 48000 iterations
Writing samples to inference.hdf.checkpoint with thin interval 64
Writing samples to inference.hdf.bkup with thin interval 64
Updating burn in
Evaluating nacl burn-in test
ACT: 3520.0
Evaluating max_posterior burn-in test
Is burned in: False
Computing autocorrelation time
ACT: inf
Validating checkpoint and backup files
Clearing samples from memory
Have 0 effective samples post burn in
Running sampler for 48000 to 50000 iterations