So I am making some parallel code using OpenMP (but this question should be reasonably applicable to other frameworks), in which I have an array of objects:
std::vector<Body> bodies;
And then I do a little parallel loop to do some things to the bodies. At the start of this parallel section, a team of threads is set up to execute the loop individually. The loop basically uses the values of foo on every Body (apart from the one in question) to update the value of bar on the body in question. So essentially no writes are being done to the values of foo on each body, and the only reads being done on bar are localised to the thread controlling that particular body; in pseudocode, it looks like this:
//create team of threads, and then this section is executed by each thread separately
for each Body i
for each Body j =/= i
i.bar += (j.foo * 2);
end for
end for
My question is whether this will, as I think it should, maintain the coherency of the cache? Because as far as I see it, none of the threads are reaching for things that are being edited by the other threads, so it should be safe, I feel. But This is quite an important point in the report that I need to write on this, so I want to be sure.
Thank you.
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