Difference between revisions of "Computer task switching from an analogy perspective"

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And rightly so. No one wants to think about all that.
 
And rightly so. No one wants to think about all that.
 
Just to generally do the right thing.
 
Just to generally do the right thing.
 
  
  
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More specific terms
  
 
'''MPI''' is a scheduler that can be told to be aware of the size of hallways,  
 
'''MPI''' is a scheduler that can be told to be aware of the size of hallways,  
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The idea of having a person capable of this planning is nice,
 
The idea of having a person capable of this planning is nice,
 
though only really has value when there is a lot of stuff ''to'' be carted around in nontrivial ways.
 
though only really has value when there is a lot of stuff ''to'' be carted around in nontrivial ways.
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SMP is like putting all the cupboards (memory) in the center to be shared.
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NUMA is like having the cupboards distributed between people/desks.
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This means you can get to your own a little faster (no management to its use),
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but to most other memory a little slower.
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Shared memory is sharing information multiple people need in a cupboard.
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You better have some conventions or protocols to when you change things,
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or will make mistakes, unknowingly.
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* you need habits like typically going via an organizer (and not directly to a random person) in the other group
 
* you need habits like typically going via an organizer (and not directly to a random person) in the other group
 
* varying group size can mean you may have to work around stragglers
 
* varying group size can mean you may have to work around stragglers
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Revision as of 15:23, 14 January 2019

This article/section is a stub — probably a pile of half-sorted notes, is not well-checked so may have incorrect bits. (Feel free to ignore, fix, or tell me)

a.k.a. "but how many cores do I make this program use?"

...or "what's this about MPIs and threads?"


Analogies