Slashdot Mirror
Does C# Measure Up?
An anonymous reader queries: "Windows::Developer is offering a detailed, quantitative examination [free login required] of C#'s performance versus Java, C, C++ and D. 'Overall the results were surprising, although perhaps unexciting, in showing that C# (and to a less extent Java) is, to a good degree, on a par in efficiency terms with its older and (presumed to be) more efficient counterparts C and C++ at least as far as the basic language features compared in this analysis are concerned,' writes the author, Matthew Wilson. I'm only an amateur coder, and confess to not understanding most of the two-part article. I'd love to hear how true programmers view his results, which are too wide-ranging to summarize easily here. How about it Slashdot, as this special edition asks, 'Can C# keep up with compiled languages like C, C++, and D or byte-code based Java?'"
While we're on the topic of C#, rnd() queries: "It's been a while now, since Mono and DotGnu have begun eroding the market power of Microsoft by creating open source implementations of C# and the Common Language Runtime. Over the weekend I loaded Mono and did some informal benchmarking of object creation, intensive message passing, massive iteration, etc., and the results show that Mono is about 90% as fast as Microsoft's implementation after a very short time. I now want to switch my .NET development over to Linux/Mono exclusively, but I want to first settle on a free alternative to Visual Studio .NET 2003. Any suggestions?"
to add....
GUI development isn't that bad in Visual Studio. In fact, it is easy as hell. With emulators like Wine available, it makes sense to develop the software with Visual Studio and its amazing debugging tools for WINDOWS and then use Wine to run it on Linux.
One could use the GTK and GNU-C to develop multi-platform software in the first place, but then you are dealing with the parent poster's problem of debugging on multi-platforms, not to mention that GTK sucks under Windows (Anyone else use GAIM?)
More than enough BS
OK lets get a few things settled.
Given: two identical applications; A, written in low level language like machine assembly, C, or C++; B, written in high level language like Java, Python, VB, hgluahalguha.
If the application is high in CPU burn (lets call it X), like oh, for (i = 0; i
If the application is copying a very large file using basic read/write system calls and large enough buffers (lets call this Y), A and B will have very similar performance.
If the application is printing hello world, they will have similar performance, although the startup costs for B may be higher, and A will probably finish executing faster.
MOST applications written today are written to solve for Y. The code that most programmers write today is NOT the CPU intensive portion. Usually the CPU intensive portion is in the library called by the programmer: rendering a box, moving things around on a storage device, making something appear on a network.
In these cases, a high or low level language makes no freaking difference on execution speed. However, your choice WILL make a huge difference on time to develop, maintainability, resultant bugginess, SECURITY, etc.
OF COURSE THERE ARE EXCEPTIONS. Maybe you're writing a routine that needs to draw lines fast, or move bytes through a network filter at 100MB/sec, or you're compressing a file, whatever. In these cases you tend to write the performance critical code in a more low level language so you have greater control over the physical machine. Sometimes you write the entire application in the low level language.
Many high level languages provide mechanisms for calling low-level code when it's necessary for performance. It's often pretty easy.
The performance argument is a red herring.
I recommend that any programmers out there try using it before discounting it. It might be especially interesting for those C++ programmers out there who don't like Java for one reason or another.
Moreover, languages like C and C++ can be used in very different ways, depending on the circumstances. You can code the "safe convenient" way using tools like STL or glib to manage strings, containers, etc. I've found that the overall performance of such an application often is in the same ballpark of a Java implementation (other than Java's obnoxious startup time).
However, C and C++ also allow you to write in a "masochistic balls-to-the-wall" mode that gives you much higher performance in exchange for 10X the programming effort. To do this, you often have to analyze your algorithms over and over until you can implement them using only stack and static structures. You avoid malloc() at all costs, avoid copying any data unless absolutely necessary, etc. You might disassemble the compiler output, run profilers and arrange data in cache-friendly patterns to squeeze out even more performance. The implementation will be much more brittle and prone to bugs, but you can often get a 10X or more speed improvement over the "natural" C or C++ implementation. Obviously, very few problems warrant this kind of attention, but making blanket statements about "comparing" other languages to C/C++ really should acknowlege the large range of performance that these languages can cover.
And this is where the .NET Framework shines, because the CLR is a generic virtual machine to which any number of languages can be compiled. Currently there are C#, C++, VB, and even Java (under the moniker J#). There has been talk of writing a Python compiler and even possibly a Perl compiler. So you can choose your language of choice, and your resulting binaries or objects will fully interoperate with the other .NET languages and class libraries.
And as far as this article is concerned, I think the interesting point is not that they're comparing apples to oranges, but just that the performance numbers for CLR-compiled C# aren't so horrible that they should scare off the majority of developers.
I really can't believe this thread. Why do people always come up with this worn out line whenever someone suggests that C++ templates are an advantage? And how come so many people have done so in replying to the same post? All but the first are (-1, Redundant), and the first is (-1, Ill-informed).
OK, please, read this carefully, for I shall write it only once (in this thread):
Java's generics are not even close to the power of C++ templates. They are glorified macros to fix a bug in the type system that should never have been there.
C++ templates were at that level around a decade ago. Today, they're used not only to create generic containers (for which they are, no doubt, very useful) but also, via metaprogramming techniques, as the tool underlying most of the really powerful developments in C++ for the past few years: expression templates, high performance maths libraries, etc.
If you didn't already know that, please read it again and understand it before proceeding.
Java's generics don't even come close to the same power. They're a cheap knock-off, aimed at just one of the uses of C++ templates, which fixes a glaring flaw in the previous Java language. For that, they serve their purpose well, but please don't pretend they're anything more.
If you disagree, post your argument. (-1, Overrated) isn't your personal censorship tool for views you don't like.
Give or take a few quirks, most recent (last five years, say) C++ compilers support all the major features acceptably well for most purposes. There are only a few issues that cause significant problems: the infamous export, Koenig look-up and partial specialisation of templates come to mind. None of these features is used very often anyway, though.
Coding standards that forbid the use of templates, exceptions and half the standard library in C++ are common, but way out of date.
By the way, I write code for a living that gets shipped on more than a dozen different C++ platforms. Alas, some of them are well pre-standard, and so don't support even basic template or exception mechanics properly, which sucks. But this is an issue we've looked into in some detail, so I'm pretty confident in my statements above.
If you disagree, post your argument. (-1, Overrated) isn't your personal censorship tool for views you don't like.
Try this:
Write a backend app in Java, and one with the same functionality in C or C++. Make sure they both read and write data to an Oracle database. Now, with stopwatch in hand, make them both run on Win2K, Cygwin, Solaris, and Linux.
Guess which language will allow you to finish first.
but you have to remember that C++ is designed to open up the power of the machine to you, not make you think a particular way or be magical for you.
The onus is on the "our language does it for you" crowd because you were not supposed to say "oh, you have to understand how the VM is working"... right?
Of course, in the end, all languages will have to tell us this "oh, yes, well, you have to know something". Of course you do! It will always be this way.
So choose the most efficient and effective language for you and learn it well, learn a different one if called for, etc.
At least, I take this to be apparent.
PS: "pyrrhonist"... right on!
-pyrrho
I posted this already... go see how blitz++ works.
It doesn't make the language butchered in the least, quite the opposite, the end result is very clear to use and the confusing part is hidden inside the classes, where it cannot cause trouble.
the thing about C++ is, sometimes things are hard, but the reason you do them anyway is because they are worth it, and you can get high levels of abstraction (arbitrarilly high) without taking runtime hits. You have the ability to control your overhead, templates are a great example, especially the examples the parent poster mentions, expression templates, and high performance math libraries.
Blitz++ uses templates in an elegant, mind blowingly cool way. It might not be clear how it works to many, but that doesn't change how it works. Truly beautiful. And it makes the code easier to read, not harder.
-pyrrho
Start up time should be a lot better in the 1.4.2 release. Last JavaOne they specifically said work was being done on that. Further improvements are in 1.5 (when it comes out).
I guess any language ends up indirectly making you think in a different way. Maybe that's the magical part.
The onus is on the "our language does it for you" crowd because you were not supposed to say "oh, you have to understand how the VM is working"... right?
Well, my point was that the languages are different in more ways than many C++ programmers (or Java programmers) realize. For instance, many C++ programmers think that finalize methods are destructors, and many of them use finalize incorrectly because of this. Then some of these programmers choose to complain loudly about Java, when the problem lies with them. They need to learn a new paradigm or their programs will continue to function incorrectly. There are definitely best practices in C++ that are bad ideas in Java.
Obviously, this works in reverse, too. You can't go from Java to C++ without changing your thinking as well. Many Java programmers have made this mistake.
Of course, in the end, all languages will have to tell us this "oh, yes, well, you have to know something". Of course you do! It will always be this way.
So choose the most efficient and effective language for you and learn it well, learn a different one if called for, etc.
Yeah, I agree. I use languages as a tool, not a crutch. If I see a problem that is better represented by Perl than Java, I'll use Perl. Or Python, or 6502 assembly...
PS: "pyrrhonist"... right on!
I like yours too. Pyrrho was cool.
Show me on the doll where his noodly appendage touched you.
Currently there are C#, C++, VB, and even Java
.NET framework correctly, there is no way to support either multiple inheritance or templates--in which case C++ cannot be accurately modeled in .NET. Nor will Java be .NETtable after 1.5, which will introduce pale imitations of templates (but imitation enough to give the CLR a hissyfit).
.NET CLR does not support multiple languages. It supports one language--C#. Its "multiple language support" comes from being able to compile down many functionally-identical languages with different syntaxes down to the same bytecodes.
.NET supports are those which are subsets of C#. And once you realize that, .NET becomes much less interesting.
.NET much in the last few months. Last I checked these things were true, but after being very unimpressed with .NET I haven't kept up with things.)
If I understand the
The
But truly different languages are not representable in the CLR. Show me how to do a Scheme continuation in the CLR, please, or export a C++ template, or a LISP macro.
The only languages
(Warning: haven't used
First, I'll ask you to please see my comments in the other response to you...
.NET claims it will support all programming languages. It doesn't. It doesn't even come close. Once you realize .NET is just another VM that can be more easily targeted by compilers, you realize that "hey, this is ... really ... not all that interesting or useful," as I said in the post which kicked all this off.
.NET or am I talking about Java? In this case, Java. (I can't confirm the 60+ languages bit, but that's the number I see. Last I heard, Java supported more languages than .NET, but this gap was rapidly closing and the numbers are a couple of months old.)
.NET interesting? It was interesting the first time Sun did it with Java. (Or, for us dinosaurs, it was interesting the first time I saw UCSD Pascal do it with their VM.) It's not interesting this second time around.
.NET useful? If you're married to the Microsoft platform, then I guess it's useful. But really, where's the huge win for .NET over Java? There isn't one. It's an alternative to Java, not really something new and innovative, not something which allows you to solve more problems than Java or even allows you to solve them all that much differently.
Done.
In fact, even his "brilliant" graph algorithms may have been top-class during his time.
As far as I can see, remember, or am concerned, Dijkstra's contributions to computational graph theory are fundamental to the field. If you think they're brilliant-in-quotation-marks, all I can ask is what you've discovered that's comparable.
That's not meant as an insult or a challenge, incidentally. It's meant to say that in hindsight many things become obvious which required real genius to see them in the first place. Dijkstra's graph algorithms are simple and straightforward, and in hindsight they're obvious--but let's not forget that the only reason they're obvious to us is because Dijkstra had the insight to see, in foresight, what's obvious in hindsight.
If in your academic mind you truly believe this,
You keep on calling me that, an "academic". The reality is I'm nothing of the sort except in the sense that I'm a graduate student. I'm a hacker, not an ivory-tower academic. I believe in solving problems and sharing those solutions with the world.
It's axiomatic that if you're faced with a problem, one of the worst things you can do is stubbornly insist that it be solved with X technique. You have to show some flexibility. You have to be able to approach the problem from different angles. For GUIs, I've found object orientation is almost always best. For scientific programming, I've found template metaprogramming best. For using computers in math theory courses, I use LISP or ML. For writing system-level software, I use C++. Etcetera.
My insistence on multiple paradigms is unequivocally not born out of "academia", a word which it seems you're using as an insult. My insistence on multiple paradigms is born out of my demand that I use the right tool for the job.
Why is it not all that interesting or useful? Because we already have that with Java. We've got a virtual machine which provides managed services and is targeted by over 60 different languages, all of which can use all the facilities of the other languages once their code has been reduced down to bytecodes. We've got a VM which allows you to interface with the native hardware to get a massive speed boost.
Am I talking about
So where is
Where is
That said, is it useful for Company A, which prefers VB, and Company B, which uses Java, to be able to collaborate on software, each using their preferred language, with their results able to be executed on a shared VM?
Sure it is. That's not what I mean when I say ".NET is neither useful nor intere