Why is C so fast, and why aren't other languages as fast or faster? [closed]

Answer 1

With modern optimizing compilers, it's highly unlikely that a pure C program is going to be all that much faster than compiled .net code, if at all. With the productivity enhancement that frameworks like .net provide the developer, you can do things in a day that used to take weeks or months in regular C. Coupled with the cheap cost of hardware compared to a developer's salary, it's just WAY cheaper to write the stuff in a high-level language and throw hardware at any slowness.

The reason Jeff and Joel talk about C being the "real programmer" language is because there is no hand-holding in C. You must allocate your own memory, deallocate that memory, do your own bounds-checking, etc. There's no such thing as new object(); There's no garbage collection, classes, OOP, entity frameworks, LINQ, properties, attributes, fields, or anything like that. You have to know things like pointer arithmetic and how to dereference a pointer. And, for that matter, know and understand what a pointer is. You have to know what a stack frame is and what the instruction pointer is. You have to know the memory model of the CPU architecture you're working on. There is a lot of implicit understanding of the architecture of a microcomputer (usually the microcomputer you're working on) when programming in C that simply is not present nor necessary when programming in something like C# or Java. All of that information has been off-loaded to the compiler (or VM) programmer.

Answer 2

C++ is faster on average (as it was initially, largely a superset of C, though there are some differences). However, for specific benchmarks, there is often another language which is faster.

https://benchmarksgame-team.pages.debian.net/benchmarksgame/

fannjuch-redux was fastest in Scala

n-body and fasta were faster in Ada.

spectral-norm was fastest in Fortran.

reverse-complement, mandelbrot and pidigits were fastest in ATS.

regex-dna was fastest in JavaScript.

chameneou-redux was fastest is Java 7.

thread-ring was fastest in Haskell.

The rest of the benchmarks were fastest in C or C++.

Answer 3

It's the difference between automatic and manual, higher level languages are abstractions thus automated. C/C++ are manually controlled and handled, even error checking code is sometimes a manual labor.

C and C++ are also compiled languages which means none of that run everywhere business, these languages have to be fine tuned for the hardware you work with thus adding an extra layer of gotcha. Though this is slightly fazing out now as C/C++ compilers are becoming more common across all platforms. You can do cross compilations between platforms. It's still not a run everywhere situation, your basically instructing compiler A to compile against compiler B same code different architecture.

Bottom line C languages are not meant to be easy to understand or reason, this is also why their referred to as systems languages. They came out before all this high level abstraction nonsense. This is also why they are not used for front end web programming. Their just not suited to the task, their mean to solve complex problems that can't be resolved with conventional language tooling.

This is why you get crazy stuff like (micro-architectures, drivers, quantum physics, AAA Games, operating systems) there are things C and C++ are just well suited for. Speed and number crunching being the chief areas.

Answer 4

It is not so much that C is fast as that C's cost model is transparent. If a C program is slow, it is slow in an obvious way: by executing a lot of statements. Compared with the cost of operations in C, high-level operations on objects (especially reflection) or strings can have costs that are not obvious.

Two languages that generally compile to binaries which are just as fast as C are Standard ML (using the MLton compiler) and Objective Caml. If you check out the benchmarks game you'll find that for some benchmarks, like binary trees, the OCaml version is faster than C. (I didn't find any MLton entries.) But don't take the shootout too seriously; it is, as it says, a game, the the results often reflect how much effort people have put in tuning the code.

Answer 5

There are a many reasons, including:

• It compiles into assembly language.
• It is statically typed.
• No garbage collection.
• No exception mechanism.
• Compiler optimizations
• Part of the philosophy of C is to keep things simple and maintain backwards compatibility, instead of adding more features.

Answer 6

There isn't much that's special about C. That's one of the reasons why it's fast.

Newer languages which have support for garbage collection, dynamic typing and other facilities which make it easier for the programmer to write programs.

The catch is, there is additional processing overhead which will degrade the performance of the application. C doesn't have any of that, which means that there is no overhead, but that means that the programmer needs to be able to allocate memory and free them to prevent memory leaks, and must deal with static typing of variables.

That said, many languages and platforms, such as Java (with its Java Virtual Machine) and .NET (with its Common Language Runtime) have improved performance over the years with advents such as just-in-time compilation which produces native machine code from bytecode to achieve higher performance.