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Why is BIND 10 written in C++ and Python?

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Re: Why is BIND 10 written in C++ and Python?

#21

Post by buster »

stefantalpalaru wrote: post #11
misnome wrote: post #5

Earlier quoted context omitted.

Why doesn't it look good for python? As far as I'm aware, Python has never been advertised as a top-performance language, and part of the advantage has always been that you can rewrite performance-critical paths in c. Adding to this, the fact that BIND is something pretty performance-intensive, I don't think this makes it look bad at all.

Because the stated goal was to use Python "whenever possible" and judging by the python2 bashing at the end of the article, the author is a true believer yet the best he could do was 17% of the total code. This also clashes with the belief in the Python community that performance is not an issue because you just rewrite those few critical sections in C/C++. How's 75% as one possible definition of "few"?

What stupid comparison is this? Of course there will be more lines of code in C++, but i bet you that 10 lines of python do more then 10 lines of C++.

As another comment puts it: How much more C++ would there be without python?

Re: Why is BIND 10 written in C++ and Python?

#22

Post by coldtea »

stefantalpalaru wrote: post #11
misnome wrote: post #5

Earlier quoted context omitted.

Why doesn't it look good for python? As far as I'm aware, Python has never been advertised as a top-performance language, and part of the advantage has always been that you can rewrite performance-critical paths in c. Adding to this, the fact that BIND is something pretty performance-intensive, I don't think this makes it look bad at all.

Because the stated goal was to use Python "whenever possible" and judging by the python2 bashing at the end of the article, the author is a true believer yet the best he could do was 17% of the total code. This also clashes with the belief in the Python community that performance is not an issue because you just rewrite those few critical sections in C/C++. How's 75% as one possible definition of "few"?

>Because the stated goal was to use Python "whenever possible" and judging by the python2 bashing at the end of the article, the author is a true believer yet the best he could do was 17% of the total code.

Of the total code of a very specific application, with very specific performance needs.

For others applications, including servers, the ratio could vary widely.

Re: Why is BIND 10 written in C++ and Python?

#23

Post by buster »

markwong wrote: post #20

based on the given criteria, wondering why Java wasn't considered.

Probably because of memory usage and garbage collection and the fact that java needs to be installed on most systems whereas C++ needs no dependencies and python comes preinstalled on the usual linux server (probably not python3 but i assume it will be some years before bind10 sees adoption for such critical infrastructure). Also he mentions specialized data structures and memory management.

Atleast i wouldn't sleep well if i know that the heart of the internet was running Java :P

Re: Why is BIND 10 written in C++ and Python?

#24

Post by alpatters »

justin66 wrote: post #9
stefantalpalaru wrote: post #3

This doesn't look good for Python: "Whenever possible, we use Python" "When necessary, we use C++" "As of right now, it ends up that about 75% of our code is C++ and 17% is Python (link) since it turns out that a lot of BIND 10 is performance-critical."

I can see what you're saying but it's worth contemplating what percentage of the total codebase that Python code would represent if it were replaced by C++ code.

I often convert python code to C++ and you'd be surprised how often the difference in loc is not that much. Certainly no hassle to do so. Not that I'm suggesting that one always should.

Several boost libraries are inspired by python and C++11 features all help to write C++ code that is surprisingly similar to python, with a bit of extra type sepcification. If you think otherwise I'd suggest you're probably thinking of the C++ of the 90s - a more C with classes, and not modern C++.

I often find it useful to develop and prototype in python and convert to C++. Most often I'm doing this because my python simulations can take days and the C++ versions hours. Often I find it is not just the performance critical areas, but it is easy enough just to wholesale convert the lot.

Re: Why is BIND 10 written in C++ and Python?

#25

Post by eksith »

denysonique wrote: post #12

Why isn't it written in Node.js?

After careful consideration, as the article mentions, ISC decided a combination of C++ and Python as being more appropriate to the goals of the project. That being safety, stability, established familiarity, speed and of course a level of guaranteed future-proof platform availability.

Read: "This is one of the cornerstones of the internet that we didn't want to piss away on novelty".

That sounded rude, and I'm sorry for that, but I don't know how else to make that point cogent.

Re: Why is BIND 10 written in C++ and Python?

#28

Post by alpatters »

jejones3141 wrote: post #19

Here's what I take from this: "C++ is by no means an easy language to work with, so the idea is that we will avoid its complexity when possible."

Avoiding its complexity does not mean avoiding it. E.g. you could avoid template metaprogramming due to its complexity whilst keeping to simpler areas of the language.

C++ is a large, multi-paradigm language. It gives you choices and one is free to abuse those choices. But having more options gives you more power to express.

I think with modern C++ style, boost and C++11 its "difficult-to-work-with" reputation is massively overstated. It is possible to write succinct code with good design and get massive performance benefits.

Re: Why is BIND 10 written in C++ and Python?

#29

Post by microtonal »

alpatters wrote: post #24
justin66 wrote: post #9

Earlier quoted context omitted.

I can see what you're saying but it's worth contemplating what percentage of the total codebase that Python code would represent if it were replaced by C++ code.

I often convert python code to C++ and you'd be surprised how often the difference in loc is not that much. Certainly no hassle to do so. Not that I'm suggesting that one always should. Several boost libraries are inspired by python and C++11 features all help to write C++ code that is surprisingly similar to python, with a bit of extra type sepcification. If you think otherwise I'd suggest you're probably thinking o…

I often convert python code to C++ and you'd be surprised how often the difference in loc is not that much.

I agree, especially with C++11 and (besides Boost) Qt. It's often the header/code separation that makes things a bit tedious, having to keep function and method signatures in-sync. Of course, if you are template-land that is not that much of a problem.

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