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From: Stefan Monnier <monnier@iro.umontreal.ca>
Newsgroups: comp.arch
Subject: Re: Is Parallel Programming Hard, And, If So, What Can You Do About It?
Date: Wed, 21 May 2025 08:23:49 -0400
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>>> Personally, I rarely use multi-threading, and when I do, it is usually
>>> in
>>> the form of using mutex locks over shared buffers.
>>> You lock the mutex if needed to copy data from one thread to another; or
>>> when doing a task that depends on the data being consistent.
>>
>> FWIW, I think these kinds of things usually fall in the scope of
>> concurrency rather than parallelism.
>
> When I run 20-copies of a FEM CFD application, each uni-process::
> am I running concurrently ?? or in parallel ?? or both ??

Both: AFAIK the choice of how to divide&spread the data and the work is
in the parallelism camp, while the choice of how to synchronize them is
in the concurrency camp.


        Stefan