Re: [boost] [xint] Third release is ready, requesting preliminary review

Subject: Re: [boost] [xint] Third release is ready, requesting preliminary review
From: DE (satan66613_at_[hidden])
Date: 2010-05-03 13:16:01

on 03.05.2010 at 20:39
 Stewart, Robert wrote :

> DE wrote:
>>  Stewart, Robert wrote :
>> > DE wrote:
>> >> i believe that mutating operations are so expensive that the cow
>> >> overhead becomes negligible
>> >> and one can live with it unless he is very pedantic
>>
>> > Once again, allow me to point out that the copy was being made in
>> > order to mutate the copy.  The COW operations are
>> > superfluous in that case.
>>
>> i understand this point
>> but i see no conflict between those two statements

> There is no conflict other than that your response was directed to
> my statement that the COW overhead was superfluous in the context I
> addressed.  Thus, using COW to satisfy the stated example pessimized the code.

it does indeed
but the pessimization is negligible compared to the cost of an
operation itself

i suddenly have remebered a rule on optimization: measure, then optimize
in other words: find a bottleneck and only then optimize the
code causing it
in this thread things look the other way around
you guys make a guess and ask to change/optimize the code using that
guess as the basis
sorry, i consider it wrong
in fact it must be like this:
- i use it in a <usecase>, i profiled it and found a bottleneck in the
following piece of code...

otherwise there is a big chance we are wasting each others time making
guesses and arguing about implementation details
because optimizations born from that may be worthless

-- 
Pavel
P.S.
if you notice a grammar mistake or weird phrasing in my message
please point it out