How to know the maximum number of concurrent requests that I can send?

Good afternoon.
I must say: I understand that my question may sound silly to maximally knowledgeable people. Background my curiosity on this subject: recently abdasa with a colleague, talking the audience about the parallel sending n queries to a certain server. It used the famous library async.js or rather, a function of parallelLimit(), which takes a collection, the limit of parallel operations, and a function-iterator. In this context, the function of the iterator doing requests to a server. A colleague said that the maximum limit that can be set equal to the number of processor cores, and if we have 4 cores, then put the limit at least 10 to run are all equal to 4. I doubted it, but as I don't know the topic deeply, I want to ask, is it?
4 answers
April 3rd 20 at 18:30
And rightly questioned. ( different browsers support different number of concurrent requests, which has nothing to do with the number of cores.
April 3rd 20 at 18:32
tell your friend
"for you, goats, pedestrian crossings built"

April 3rd 20 at 18:34
Advise a colleague to read on the subject of threads and processes. Then let them open a dozen Windows in the browser and then in the task Manager wondering what processes are executed more than cores on the machine.
April 3rd 20 at 18:36
if you need more, then,, ....
so solved the problem of fotohosting in 00h

crutch from a specific visitor - go to the settings of the browser and rotate only (Max.
requests for one domain)

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