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From: mitchalsup@aol.com (MitchAlsup1)
Newsgroups: comp.arch
Subject: Re: Is Parallel Programming Hard, And, If So, What Can You Do About
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Date: Tue, 20 May 2025 22:11:41 +0000
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On Tue, 20 May 2025 20:06:13 +0000, Stefan Monnier wrote:

>> 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 ??

Also note: I need to use the "affinity" service under taskMangler
so that only 4 processes share a core, performance goes up by roughly
20%.

The CFD simulations typically run for 10 hours (each, wall clock time),
and every second; dump out a dozen KB of compressed data (each). The
disk load is low enough I can do other "stuff" on the computer as
long as I affinitize the heavy loads to 5 of the 6 cores.

>
>
>         Stefan