[cks]

"I’d even argue that the main reason kernel code tends to be efficient is not because it’s written in C but because it’s written with parallelism and reentrancy in mind, by people who understand those issues."

With this arguing, isn't it reasonable to assume that a project Foo written in C or C++ is faster than an equivalent written in Java simply because the author writing project Foo in C/C++ likely understands performance by choosing C/C++ in the first place? (I am not saying anything about the performance of a certain language implementation)

The author also argues from a performance critical application perspective. What about desktop applications where perceived performance rather acts like a quality property? I know many people that shy away from using desktop Java and even .NET applications simply because they feel sluggish and waste memory. I don't care if the Java application is as fast in pure algorithmic performance.

If I can choose between using two equivalent C/C++ or Java/.NET applications I will choose the C/C++ application. I still think this is a good assumption.

[j_baker]

"With this arguing, isn't it reasonable to assume that a project Foo written in C or C++ is faster than an equivalent written in Java simply because the author writing project Foo in C/C++ likely understands performance by choosing C/C++ in the first place?"

No, not at all. First of all, don't assume that someone knows what they're doing just by choosing C or C++ over Java. There are plenty of dumb C/C++ programmers out there, and a well-written Java program is always going to outperform a poorly written C/C++ one.

Secondly, remember that Java programs may actually be faster than C/C++ programs. Programs written in C/C++ require more time and knowledge to performance tune. Writing something in Java (or other high-level language) allows the author to spend more time focusing on the big picture issues rather than having to deal with a lot of lower-level issues.

[btmorex]

"Secondly, remember that Java programs may actually be faster than C/C++ programs. Programs written in C/C++ require more time and knowledge to performance tune. Writing something in Java (or other high-level language) allows the author to spend more time focusing on the big picture issues rather than having to deal with a lot of lower-level issues."

I'm not against Java and I'll even admit that theoretically I could imagine a situation where a Java program ended up being faster, but in reality, that never happens.

In reality, we always end up in situations like utorrent vs. azureus (for those that don't know, utorrent is written in c++ and pretty much better than azureus in every way). In fact, I can't really think of one instance where a piece of java software is better than an equivalent written in c or c++ (outside of developer tools, because those aren't really directly comparable anyway)

[_cbsz]

> for those that don't know, utorrent is written in c++ and pretty much better than azureus in every way

The Azureus/Vuze DHT is a lot nicer than the Mainline DHT (which uTorrent supports), it's just not documented, there are no other implementations, and this statement probably does not apply to code quality.

[tbrownaw]

Secondly, remember that Java programs may actually be faster than C/C++ programs. Programs written in C/C++ require more time and knowledge to performance tune. Writing something in Java (or other high-level language) allows the author to spend more time focusing on the big picture issues rather than having to deal with a lot of lower-level issues.

No. C++ may permit more extensive performance tuning, but the same level of tuning shouldn't take any longer in C++ than in Java. And really I'd say C++ as a language is at least as high-level as Java (especially considering templates), just more of the libraries you'll want to build on are shipped separately.

[cageface]

Except Java has a GC. In fact I'd say bringing GC into the mainstream may have been Java's major contribution to the art of software development.

[gryan]

"I’d even argue that the main reason kernel code tends to be efficient is not because it’s written in C but because it’s written with parallelism and reentrancy in mind, by people who understand those issues."

It's used to build kernels because it doesn't require multiples of the needed RAM in order for the memory management to be timely.

[ldh]

isn't it reasonable to assume that a project Foo written in C or C++ is faster than an equivalent written in Java simply because the author writing project Foo in C/C++ likely understands performance by choosing C/C++ in the first place?

I think that's kind of a stretch.

[kunley]

"With this arguing, isn't it reasonable to assume that a project Foo written in C or C++ is faster than an equivalent written in Java simply because the author writing project Foo in C/C++ likely understands performance by choosing C/C++ in the first place? (I am not saying anything about the performance of a certain language implementation)"

The point is that if someone is able to choose C/C++ means that he's much more smarter than many existing Java programmers.

Sad but true.

[rv77ax]

Agree.

Plus, C/C++ programmer can do a refactoring or optimizing more in their code, even in low level, with the limit is only their time and skills, but in high level languages like Java/.NET optimizing level is stuck in VM.