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Questions tagged [multiple-processes]

the execution of multiple concurrent processes in a system

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How to read a large file once, and share it with other processes?

I have a bunch of processes forked from the same parent processes. And they need to read the same large file during initialization. Unfortunately, I do not have any control over the parent process. Is it possible that one process open the file, read…
tianyapiaozi
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Sending 2D Int Array with MPI_Send and Recv

I am trying to send a 2D integer array of arbitrary length from slave processes to the master but I keep getting a segmentation fault. As MPI is quite difficult to debug, I'm not certain that the issue has to do with the send/recv but if it's not…
Jarrod Cabalzar
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Multiple processes pushing elements to list STL C++

I have multiple preforked server processes which accept requests to modify a shared STL C++ list on a server. Each process simply pushes a new element at the end of the list and returns the iterator. I'm not sure how should each process attempt to…
studying algorithms
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Robotium Unit Testing on an application having multiple processes

I have written an application running activities in multiple processes. I tried Robotium by creating a new test project set target package to my application. When I executed it, the test stopped with the following error message: Error in…
warenix
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How to store result to dataframe from multiple processes with multiple parameter in python

The original code is as follows: result_m2 = pd.DataFrame(columns = colnames,index = main_dict.keys()) for r in range(rand): for s in [0.5,0.6,0.7,0.8]: for n in num: for k,t in main_dict.items(): colname =…
user4672728
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multiple task management in python3

Here I need to run many sub-tasks in 2 steps: run multiple programs at the same time. These programs are some external executable programs. Wait for all programs in step 1 to end before running the next function I known the multipleprocessing…
Lex
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Append to empty list with multiprocessing pool

From a broader level, this is what I am trying to do - append to an empty list an item it reads from the elements list with multiprocessing pool, but this is printing an empty list. Any idea where I am going wrong, or any alternative to achieve the…
user106742
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how to split a large csv writing to several files by multiple processing in python?

I have a very large csv file (40G), and I want to split it into 10 df by column and then write each to csv file (about 4G each). To save time, I choose multiple processing to process it. But I found the mp doesn't work, it still processes one by…
roy_wang
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TCL - trying to execute proc in parallel but getting an odd Java error

I'm following the example from here https://wiki.tcl-lang.org/page/Execute+in+Parallel+and+Wait But when I run a simple code like this I get an error: child process exited abnormally and the error is "Error: Could not find or load main class Caused…
James Dean
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How do I write to a socket that I created in another file in C?

I have two c files, server and client. The server listens for and accepts a connection request from a client, and then it waits to print out a message given to it by the client. The connection process works perfectly, but I don't know how to get it…
Brandon O
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Want to generate multiple pdf in single file using mpdf

I am generating multiple files using mpdf lib, I don't want to generate all files separately, I want to generate files in one pdf separated by pages. I added the addpage method to generate a single file but having an issue, my first-page printing as…
Hadayat Niazi
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Are processes the same as concurrency in django-post_office?

I am using django-post_office to send c.10,000 emails in a single task each morning. It's possible to do this via the function send_queued(processes=1, log_level=None) in a celery task. I understand it's best practice to run celery with concurrency,…
alias51
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fork() does not run parallel

I am new to programming processes and my basic program doesn't really work as I expected. I am running this code on Ubuntu 18.04 on a Oracle VM. Here is the code: #include #include #include #include int…
hltbyr
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How to catch all signals from child processes, while using poll for multiple file descriptors?

So I have this assignment and they tell me that I have to create a process tree (with number_of_children forks), send some messages from bottom level workers to the root of the process tree and finally before the workers exit, they must send a…
Vissarion Moutafis
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Cassandra: Is it normal to have so many gc.log processes

I am quite new to cassandra, so if someone can explain me what I see here. I have a cassandra ring with 16 nodes(simple strategy) and if I use htop on the nodes I see too many gc.log processes taking place which also I think occupy a lot of memory!…
Des0lat0r
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