Here is a simple GNU parallel command that creates a file called “example_i.txt” inside an existing directory called “example_i”. It does this four times, for i from 1 to 4, with one job per core: Not very exciting, I know. The problem appears when I try to run this via python (v3.9) u…
Tag: multiprocessing
Why did multiprocessing giving me EOFError : Ran out of Input Error?
videoPlayerThreading is my own made library to basically making 2 class with each using threading to get and show frames. objDect is also my own library to basically return frame after object detection. I got EOFError : Ran out of Input error and from the traceback I think it is caused by the multiprocessing …
patch object spawned in sub-processs
I am using multiprocessing package for crating sub-processes. I need to handle exceptions from sub-process. catch, report, terminate and re-spawn sub-process. I struggle to create test for it. I would like to patch object which represent my sub-process and raise exception to see if handling is correct. But it…
Using multiprocessing on Image processing
I’m trying to speed up my processing of a PIL.Image, where I divide the image into small parts, search for the most similar image inside a database and then replace the original small part of the image with this found image. This is the described function: Now I wanted to parallelize this function, sinc…
Convert a normal python code to an MPI code
I have this code that I would like to edit and run it as an MPI code. The array in the code mass_array1 is a multi-dimensional array with total ‘iterations’ i*j around 80 million. I mean if I flatten the array into 1 dimensional array, there are 80 million elements. The code takes almost 2 days to…
what is the underlying process of python multiprocess queue?
Does anyone explain the python multiprocessing queue communication in detail? What’s happening when the parameter been put into the queue? I have a snippet of code, which is confusing me. and the output is: why do I have this inconsistency? I see the doc saying ” When an object is put on a queue, …
Plotting the pool map for multi processing Python
How can I run multiple processes pool where I process run1-3 asynchronously, with a multi processing tool in python. I am trying to pass the values (10,2,4),(55,6,8),(9,8,7) for run1,run2,run3 respectively? Answer You just need to use method starmap instead of map, which, according to the documentation: Like …
Am I parallelizing this right?
I basically have to obtain a certain probability distribution by sampling from a sample of 5000 matrices. So I just need to count how many times element X occurs in the position (i,j) of these 5000 matrices. Then, I save these [values and counts] in a dictionary. That said, I thought it could be a good idea t…
how do POST API requests use parallel processing in python? requests.exceptions.ConnectionError:
I have code like this: in file data.json contains 500 records, for example: in BASE_URL there is data like this: expected output after POST API: with my code above, the data that enters the url is only 420 records, even though my data.json is 500 records. how do I solve this so that I post 500 records to url.…
Packages that are imported are not recognized during parallel computing?
I’m running the function get_content in parallel setting with multiprocess.Pool. Then it throws out an error NameError: name ‘session’ is not defined. Clearly, I defined it with session = requests.Session() . Could you please elaborate on this issue? Answer First of all, your import statemen…