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From: "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com>
Newsgroups: comp.arch
Subject: Re: Memory ordering
Date: Tue, 30 Jul 2024 13:00:17 -0700
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On 7/30/2024 12:56 PM, Chris M. Thomasson wrote:
> communication between cores _should_ be rare, rare as can be. The 
> software "should" design things to strive to reduce this down to the 
> embarrassingly parallel level. However, misusing, say wrt a bug in the 
> core mapping wrt affinity masks and such can increase core to core 
> communication/traffic... Not good. Terrible case, the traffic is for a 
> remote core, not all that close (physically) to the current core: The 
> core running the code that wants it to deal with another node so to 
> speak. NUMA...
> 
> If a core/node _must_ communicate with another core/node, the locality 
> in the graph should allow the core/node to "converse" with a "local" 
> core/node as in "gain the closest core/node to the source"!

Embarrassingly parallel workloads "ideally" should have everything 
working independently...