On January 19, 2016 09:39:17 Knoll Lars <lars.kn...@theqtcompany.com> wrote:
> On 15/01/16 23:20, "Development on behalf of Thiago Macieira" > <development-boun...@qt-project.org on behalf of thiago.macie...@intel.com> > wrote: > >>On Friday 15 January 2016 18:42:43 Marc Mutz wrote: >>> And you will see it over and over again until enough people are fixing >>> premature pessimisations in existing Qt code. There's a notable increase >>> already. But it takes a long time to turn a supertanker around... >> >>Some of us call them "trade-offs". Every trade-off is a pessimisation >>somewhere for an optimisation somewhere else. Often, they're not measured in >>the same units or not quantifiable at all. >> >>API quality and consistency fall under those definitions. > > Exactly this. > >> >>> And no, I cannot believe that using the Qt containers leads to faster >>> applications. It may lead to applications faster, but not to faster >>> applications. >> >>Exactly. TTM is a significant factor and we all know Paretto's Law (80-20 >>rule). > > And this. Let’s not forget to ask ourselves the question why many developers > use Qt in C++ development, often even in the case where they don’t need a UI. > For the past 20 years a lot of our focus has been on making development easy, > and creating APIs that serve that goal. This means that we are in many case > optimising for TTM more than for ultimate speed. > > I think we agree that std containers are in many cases faster than the Qt > containers. But they are harder to use and especially developers that come > from other languages often appreciate the ease of use of the Qt containers. > > The main question IMO is how we can bring these two worlds closer together > for Qt 6 (or maybe even to some extent in Qt 5.x). I think we should start minimal and try to layer QVector over std::vector. If you want performance you use in many cases a vector. The second important item would be IMHO benchmarks, maybe we use google benchmark which has some nice threading feature. Without benchmarking discussions get IMHO easily non substantial. > Cheers, > Lars > > _______________________________________________ > Development mailing list > Development@qt-project.org > http://lists.qt-project.org/mailman/listinfo/development -- Sent from cellphone, sorry for the typos _______________________________________________ Development mailing list Development@qt-project.org http://lists.qt-project.org/mailman/listinfo/development
