c++ - does .so size affect virtual function performance -


recently, met performance problem. in vtune result, virtual function cost no.1 cost, when reduce size 48m 37m, performance seems better, raise 3.9%.

i wanna know, .so size realy affect virtual function performance, if so, why? thanks!

it not purely size (though of course affects paging after program loaded), number of adjustments loader must make when loading program. can see measured setting environment variable

ld_debug=statistics

virtual functions in particular require lot of adjustments during loading. discussion on this,


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