[Interest] Qtcontainerbench std::vector vs QVector

Allan Sandfeld Jensen kde at carewolf.com
Tue Jul 28 10:15:39 CEST 2015

On Monday 27 July 2015, Gunnar Roth wrote:
> Hi Constantin.
> Thank you for looking at my benchmark.
> > Am 24.07.2015 um 08:57 schrieb Constantin Makshin <cmakshin at gmail.com>:
> > 
> > Well, after looking at the code I can say that the was you wrote this
> > benchmark "abuses" the QVector's copy-on-write semantic, making it
> > somewhat biased towards std::vector — you use only non-const versions of
> > QVector::begin(), QVector::end() and indexing methods. That leads to a
> > lot of [obviously non-free] checks for sharing and possible detachment.
> Actually imo this is the most important case. Why should i iterate	over a
> vector and not change the values? If i search in a vector it should be
> sorted. The sorted case was tested in the other tests together with map,
> but not the const case, so i added that now, but there is not much of a
> difference here.
To process the values? This in my opinion the most common case, which is why 
we have things such as foreach and recommend people to use const references 


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