c++ - is it necessary to explicitly limit the number of threads -

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when running multithreaded application, necessary explicitly specify maximum number of threads used application, or linux administrate itself? if linux handles itself, expect "social", in sense cpu divided between users. maybe wrong this?

some systems have maximum number of threads system can cope with, systems run out of memory [of kind] before happens.

if threads "not doing much", can have many (although handling several thousand threads may cause things run slower because every , again, system have "walk" every thread in system). if threads heavy in calculations , such, it's "nice" other processes in system leave spare cpu capacity processes.

so, isn't set in stone, depends on trying achieve. , of course, overall system intended - if task model aerodynamics of new car bmw, using 99.999% of cpu aerodynamics calculation fine. if machine dedicated web-server, using 99.99% of cpu serve web-pages perectly fine. if it's someone's desktop machine use browse web, write emails , compile code on, using 99.99% of available cpu fourier transform music collection check duplicate songs not ideal solution.


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