Code bloat

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Code bloat is the production of code that is perceived as unnecessarily long, slow, or otherwise wasteful of resources.

Some techniques for reducing code bloat include:

refactoring commonly-used code sequence into a subroutine, and calling that subroutine from several locations, rather than copy and pasting that sequence at each of those locations,
re-using subroutines that have already been written, rather than re-writing them again from scratch.

Code bloat can also be caused by inadequacies in the language in which the code is written, or inadequacies in the compiler used to compile the language. An example of this is the template system employed in C++. A naive compiler implementing this feature can introduce versions of a templated function for every type it is used with. This in turns leads to compiled functions that may never be used, thus resulting in code bloat. More sophisticated compilers and linkers detect the superfluous copies and discard them, reducing the bloat.

The difference in code density between various languages is so great that often less memory is needed to hold both a program written in a "compact" language (such as Microsoft P-Code or threaded code), plus an interpreter for that compact language (written in native code), than to hold that program written directly in native code.

There are a few cases where there is a space-time tradeoff -- in those cases, a larger program runs faster than a smaller program. But in most cases, making a program larger will also make it run slower.

Code bloat

See also