Re: [boost] [review] The review of Boost.DoubleEnded starts today: September 21 - September 30

Subject: Re: [boost] [review] The review of Boost.DoubleEnded starts today: September 21 - September 30
From: Thorsten Ottosen (tottosen_at_[hidden])
Date: 2017-10-13 17:13:50

Den 03-10-2017 kl. 00:02 skrev Benedek Thaler via Boost:

> Re-run results in very similar results.
> I think the numbers are convincing in favor of devector::unsafe_push_back.

There is not a huge difference between devector and vector. If I take my 
test where I try to confuse the branch predictor and alter just 1 flag: 
"favor small code" instead of "favor fast code", then I get:

32 bit:

10E3    63.8728 42.2238
10E4    62.2564 40.5588
10E5    62.0731 40.2956
10E6    62.2532 40.2451
10E7    62.3553 43.5931

64 bit:

10E3    29.2422 24.6654
10E4    28.3354 24.246
10E5    28.2262 23.7662
10E6    28.2777 23.8788
10E7    28.3777 23.8641

I think that is a good example of how the compiler can play tricks on 
you. And this is major reason we should always strive after providing 
abstractions with zero overhead.

kind regards

Thorsten