Is concurrency hard?

[Lyn Headley]

> We are used to handling data where everybody has their own private
> copy of a data structure.
> If I say "think of the number 2007" - then I send a sound message
> to my listeners - each one
> of them who hears the message forms their own private mental image
> of "2007" - there is no shared
> data structure.
> 

I'm not sure about this.  In fact I think we are constantly working
on both a sequential and concurrent level with both shared data
structures and parallelism.  Take an academic lecture.  We are all in
the same room and more importantly share the same atmosphere which
transmits our messages.  Only one of us can use this atmosphere at a
time and we have to negotiate access to it by raising our hands and
having a scheduled speaker. Furthermore there is a shared sense that
what is going on is a lecture.  coughs and throat clearing are
defined as peripheral.

But maybe that was actually your point.  The only thing that is
shared is the channel.  I suppose that's not a data structure.  But
it's a resource.  Is that right?

Lyn Headley
UCSD Communication and Science Studies



	
		
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