- Erlang - Web Programming
- Erlang - Drivers
- Erlang - Performance
- Erlang - Concurrency
- Erlang - OTP
- Erlang - Distributed Programming
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- Erlang - Databases
- Erlang - Emails
- Erlang - Processes
- Erlang - Funs
- Erlang - Binaries
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- Erlang - Pattern Matching
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- Erlang - Exceptions
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- Erlang - Tuples
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- Erlang - File I/O
- Erlang - Lists
- Erlang - Strings
- Erlang - Numbers
- Erlang - Recursion
- Erlang - Modules
- Erlang - Functions
- Erlang - Decision Making
- Erlang - Loops
- Erlang - Operators
- Erlang - Variables
- Erlang - Data Types
- Erlang - Shell
- Erlang - Basic Syntax
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Erlang - Performance
When talking about performance the following points need to be noted about Erlang.
Funs are very fast − Funs was given its own data type in R6B and was further optimized in R7B.
Using the ++ operator − This operator needs to be used in the proper way. The following example is the wrong way to do a ++ operation.
Example
-module(helloworld). -export([start/0]). start()-> fun_reverse([H|T]) -> fun_reverse(T)++[H]; fun_reverse([]) -> [].
As the ++ operator copies its left operand, the result is copied repeatedly, leading to quadratic complexity.
Using Strings − String handpng can be slow if done improperly. In Erlang, you need to think a pttle more about how the strings are used and choose an appropriate representation. If you use regular expressions, use the re-module in STDLIB instead of the obsolete regexp module.
BEAM is a Stack-Based Byte-Code Virtual Machine − BEAM is a register-based virtual machine. It has 1024 virtual registers that are used for holding temporary values and for passing arguments when calpng functions. Variables that need to survive a function call are saved to the stack. BEAM is a threaded-code interpreter. Each instruction is word pointing directly to executable C-code, making instruction dispatching very fast.