Memory usage is growing with the iterations

Describe the bug

Memory usage is growing with iterations.

To Reproduce

It should work with any kind of audio file but I can send the considered file if needed.

import librosa
import matplotlib.pyplot as plt
import os
import psutil

def foo():
    y, sr = librosa.load("clip_04.wav", sr=22050, offset=600, duration=60)
    spec_mag = abs(librosa.stft(y, n_fft=2048, hop_length=1024))
    spec_db = librosa.amplitude_to_db(spec_mag)
    return 42

def main():

    process = psutil.Process(os.getpid())

    array = []

    for i in range(100):
        print(i)
        foo()
        m = int(process.memory_info().rss / 1024**2)
        array.append(m)

    plt.figure()
    plt.plot(array)
    plt.xlabel('iterations')
    plt.ylabel('MB')
    plt.show()

if __name__ == '__main__':
    main()

Expected behavior

Memory usage should be constant.

Screenshots

Software versions

Darwin-19.6.0-x86_64-i386-64bit
Python 3.7.9 (default, Aug 31 2020, 07:22:35) 
[Clang 10.0.0 ]
NumPy 1.19.5
SciPy 1.5.2
librosa 0.8.0
INSTALLED VERSIONS
------------------
python: 3.7.9 (default, Aug 31 2020, 07:22:35) 
[Clang 10.0.0 ]

librosa: 0.8.0

audioread: 2.1.8
numpy: 1.19.5
scipy: 1.5.2
sklearn: 0.23.2
joblib: 0.17.0
decorator: 4.4.2
soundfile: 0.10.2
resampy: 0.2.2
numba: 0.51.2

numpydoc: None
sphinx: None
sphinx_rtd_theme: None
sphinxcontrib.versioning: None
sphinx-gallery: None
pytest: None
pytest-mpl: None
pytest-cov: None
matplotlib: 3.2.2
presets: None

[vincent-powder]

I’ll try to use soundfile.read() with offset and duration constraints. I’ll post here the results of my findings. Thanks again for helping me on this.

[vincent-powder]

Hello @bmcfee, I’ve used the code you’ve sent to read the wav file and here are my findings:

• If I read the entire wav file, the memory usage is constant
• If I use an offset, the memory usage is constant
• If I use a custom duration, the memory usage increases As you pointed out, the problem is probably not related to Librosa. Thanks again for investigating.