Author pitrou
Recipients alecsandru.patrascu, benjamin.peterson, brett.cannon, pitrou, serhiy.storchaka, skrah, vstinner, yselivanov
Date 2016-02-04.21:35:27
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Le 04/02/2016 21:42, Alecsandru Patrascu a écrit :
> 
> To compress all of the above, the main reason for this speedup is the
> reduction of the code path length and having the useful function
> close together, so that the CPU will be able to prefetch them in
> advance and use them instead of trowing them away because they are
> not used.

I'm expecting this patch to have an impact on executable or library
size, but not really on runtime performance, as the CPU instruction
cache only fetches whichever pieces of code are actually called.  In
other words, unused sections of code should remain cold wrt. the CPU
caches.  Apart from more or less random aliasing effects (and perhaps
TLB effects, but those should be very minor) I'm surprised that it has
positive performance effects.  But since you work at Intel, perhaps you
know things that I don't ;-)

Also any name starting with Py_ or _Py_ is an API that may be called by
third-party code, so it shouldn't be removed at all...
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2016-02-04 21:35:27pitrousetrecipients: + pitrou, brett.cannon, vstinner, benjamin.peterson, skrah, serhiy.storchaka, yselivanov, alecsandru.patrascu
2016-02-04 21:35:27pitroulinkissue26285 messages
2016-02-04 21:35:27pitroucreate