How to Solve the Python Memory Error

In this article, I want to share how I solved python memory errors when I get started building an application.

What is Memory Error?

Python Memory Error or, in layman’s terms, you’ve run out of memory in your RAM to run your code.

When you get this error, it means you’ve loaded all of the data into memory. Batch processing is recommended for big datasets. Rather than loading the complete dataset into memory, save it to your hard disc and access it in batches.

Your program has run out of memory, resulting in a memory error. This indicates that your software generates an excessive number of items. In your case, you’ll need to look for areas of your algorithm that are taking a significant amount of RAM.

A memory error occurs when an operation runs out of memory.

Types of Python Memory Error

Following are the types of Python Memory Error

1. Unexpected Memory Error in Python
2. Python Memory Error Due to Dataset
3. Python Memory Error Due to Improper Installation of Python
4. Out of Memory Error in Python
5. Memory error in Python when 50+GB is free and using 64bit python?

1 - Unexpected Memory Error in Python

If you receive an unexpected Python Memory Error while having plenty of RAM, it’s possible that you’re running a 32-bit Python installation.

A Simple Solution to Unexpected Python Memory Error: Your software has used up all of the virtual address space available to it. It’s most likely because you’re using a 32-bit Python version. Because 32-bit applications are limited to 2 GB of user-mode address space in Windows (and most other operating systems).

We Python Poolers advocate installing a 64-bit version of Python (if possible, upgrade to Python 3 for other reasons); it will consume more memory, but it will also have access to a lot more memory space (and more physical RAM as well).

The problem is that 32-bit Python has only 4GB of RAM. Because of the operating system overhead, this can decrease even more if your operating system is 32-bit.

2 - Python Memory Error Due to Dataset

Another choice, if you’re working with a huge dataset, is dataset size, which has previously been mentioned in relation to 32-bit and 64-bit versions. Loading a huge dataset into memory and running calculations on it, as well as preserving intermediate results of such computations, can quickly consume memory. If this is the case, generator functions can be quite useful. Many prominent Python libraries, such as Keras and TensorFlow, include dedicated generator methods and classes.

3 - Python Memory Error Due to Improper Installation of Python

Memory Errors can also be caused by improper Python package installation. In reality, before resolving the issue, we had manually installed python 2.7 and the packages that I need on Windows. After wasting nearly two days trying to figure out what was wrong, we reloads everything using Conda and the issue was resolved.

Conda is probably installing improved memory management packages, which is the major cause. So you might try installing Python Packages using Conda to see if it fixes the Memory Error.

4 - Out of Memory Error in Python

If an attempt to allocate a block of memory fails on most systems, an “Out of Memory error” is returned, however, the core cause of the problem almost never has anything to do with being “out of memory.” That’s because the memory manager on almost every modern operating system will happily use your available hard disc space to store pages of memory that don’t fit in RAM; your computer can usually allocate memory until the disc fills up, which may result in a Python Out of Memory Error (or a swap limit is reached; in Windows, see System Properties > Performance Options > Advanced > Virtual memory).

To make matters worse, every current allocation in the program’s address space might result in “fragmentation,” which prevents further allocations by dividing available memory into chunks that are individually too tiny to satisfy a fresh allocation with a single contiguous block.

• When operating on a 64bit version of Windows, a 32bit application with the LARGEADDRESSAWARE flag enabled has to access to the whole 4GB of address space.
• Four readers have contacted in to say that the gcAllowVeryLargeObjects setting eliminates the .NET restriction. No, it doesn’t. This setting permits objects to take up more than 2GB of memory, but it limits the number of elements in a single-dimensional array to 231 entries.

How can I explicitly free memory in Python?

If you’ve written a Python program that uses a huge input file to generate a few million objects, and it’s using up a lot of memory, what’s the best approach to inform Python that part of the data is no longer needed and may be freed?

This problem has a simple solution:

With gc.collect, you may force the garbage collector to release an unreferenced memory ().

As illustrated in the example below:

import gc

gc.collect()

Memory error in Python when 50+GB is free and using 64bit python?

On some operating systems, the amount of RAM that a single CPU can manage is limited. So, even if there is sufficient RAM available, your single thread (=running on one core)  will not be able to handle it anymore. But I’m not sure if this applies to your Windows version.

How to put limits on Memory and CPU Usage

To limit a program’s memory or CPU use while it is executing. So that we don’t have any memory problems. To accomplish so, the Resource module may be utilized, and both tasks can be completed successfully, as demonstrated in the code below:

Code1: Restrict CPU time

# importing libraries 
import signal 
import resource 
import os 
 
# checking time limit exceed 
def time_exceeded(signo, frame): 
    print("Time's up !") 
    raise SystemExit(1) 
 
def set_max_runtime(seconds): 
    # setting up the resource limit 
    soft, hard = resource.getrlimit(resource.RLIMIT_CPU) 
    resource.setrlimit(resource.RLIMIT_CPU, (seconds, hard)) 
    signal.signal(signal.SIGXCPU, time_exceeded) 
 
# max run time of 15 millisecond 
if __name__ == '__main__': 
    set_max_runtime(15) 
    while True: 
        pass

Code 02: In order to restrict memory use, the code puts a limit on the total address space

# using resource 
import resource 
 
def limit_memory(maxsize): 
    soft, hard = resource.getrlimit(resource.RLIMIT_AS) 
    resource.setrlimit(resource.RLIMIT_AS, (maxsize, hard)) 

Ways to Handle Python Memory Error and Large Data Files

• Allocate More Memory
• Work with a Smaller Sample
• Use a Computer with More Memory
• Use a Relational Database
• Use a Big Data Platform

Conclusion

So this is all about this story, in this story we covered many ways to handle python memory errors.

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