问题
python: 2.7
Ubuntu: 18.04
matpltolib: 2.2.2
I have a client GUI that get information from a server and displays it. I see memory leak and change in CPU consumption with time. The picture below shows a change in CPU and memory utilization after restarting the client with GUI (~25 seconds from the right, aligned with a spice in network traffic).
The CPU graph has a dip in the CPU utilization showing that CPU usage is different before and after the restart of program.
The Memory graph shows a large drop in the memory utilization and then slight increase due to initialization of the same program.
The Network graph has a spike because the client requests all data from the server for visualization.
I suspect it is something to do with matplotlib. I have 7 figures that I rechart every 3 seconds.
I have added the image of my GUI. The middle 4 graphs are the history charts. However, I am binning all data points in 300 bins since I have ~ 300 pixels in that area. The binning is done in a separate thread. The data arrays( 2x1 000 000 points, time and value) that store the information are created from the very beginning to ensure that I don't have any memory runaway problem when my datasets grow. I do not expect the datasets to grow beyond that since the typical experiment runs at 0.1-0.01 Hz which will take several million seconds to reach the end.
Question: If it is Matplotlib, what can I do? If it is not, what else could it be?
added Sept 6 2018: I thought of adding another example. Here is the screenshot of CPU and memory usage after I closed the GUI. The code ran for ~ 3 days. Python 2.7, Ubuntu 18.04.1.
回答1:
Thank you, everyone, for helpful comments. After some struggle, I have figure out the way to solve the problem. Unfortunately, I have made several changes in my code, so I cannot say definitively what actually helped.
Here what was done:
all charting is done in a separate thread. The image is saved in a buffer as a byte stream with io.Bytes() and later passed to the GUI. This was important for me to solve another problem(GUI freezes while charting with matplotlib).
create a new figure(figure = Figure(figsize=(7,8),dpi=80)) each time you generate the plot. previously I have been reusing the same figure (self.figure = Figure(figsize=(7,8),dpi=80)).
来源：https://stackoverflow.com/questions/52040720/matplotlib-memory-and-cpu-leak