How can I release memory after creating matplotlib figures

I have several matlpotlib functions rolled into some django-celery tasks.

Every time the tasks are called more RAM is dedicated to python. Before too long, python is taking up all of the RAM.

QUESTION: How can I release this memory?

UPDATE 2 – A Second Solution:

I asked a similar question specifically about the memory locked up when matplotlib errors, but I got a good answer to this question .clf(), .close(), and gc.collect() aren’t needed if you use multiprocess to run the plotting function in a separate process whose memory will automatically be freed once the process ends.

Matplotlib errors result in a memory leak. How can I free up that memory?

UPDATE – The Solution:

These stackoverflow posts suggested that I can release the memory used by matplotlib objects with the following commands:

.clf(): Matplotlib runs out of memory when plotting in a loop

.close(): Python matplotlib: memory not being released when specifying figure size

import gc
gc.collect()

Here is the example I used to test the solution:

import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
from pylab import import figure, savefig
import numpy as np
import gc      

a = np.arange(1000000)
b = np.random.randn(1000000)

fig = plt.figure(num=1, dpi=100, facecolor='w', edgecolor='w')
fig.set_size_inches(10,7)
ax = fig.add_subplot(111)
ax.plot(a, b)

fig.clf()
plt.close()
del a, b
gc.collect()

Answers:

Thank you for visiting the Q&A section on Magenaut. Please note that all the answers may not help you solve the issue immediately. So please treat them as advisements. If you found the post helpful (or not), leave a comment & I’ll get back to you as soon as possible.

Method 1

Did you try to run you task function several times (in a for) to be sure that not your function is leaking no matter of celery?
Make sure that django.settings.DEBUG is set False( The connection object holds all queries in memmory when DEBUG=True).

Method 2

import matplotlib.pyplot as plt
from datetime import datetime
import gc

class MyClass:
    def plotmanytimesandsave(self):
        plt.plot([1, 2, 3])
        ro2 = datetime.now()
        f =ro2.second
        name =str(f)+".jpg"
        plt.savefig(name)
        plt.draw()
        plt.clf()
        plt.close("all")


for y in range(1, 10):
    k = MyClass()
    k.plotmanytimesandsave()
    del k
    k = "now our class object is a string"
    print(k)
    del k
    gc.collect

with this program you will save directly as many times you want without the plt.show() command. And the memory consumption will be low.

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0