Why in functional programming languages recursion is faster compare to cycle?
Hi folks. I haven't written anything in a long time but now I have interesting topic to share.
You probably know that in Java recursion is much slower compare to loops. And It makes sense, because in recursion each time is created some stack frame. Each stack frame require some memory allocation and so on. So when we use recursion all time time during invocation your size of stack frames increasing. Same stuff in C++/C and in C#.
You can check it by writing Fibonacci numbers i.e.
But recently I figure out that in Haskell recursion works faster. And in mostly functional programming languages. Bot of course id depends on algorithm. The main reason is - Compiler is better in optimizing pure functions. He can make optimization more eagerly and aggressive.
"The key concept here is purity: a pure function is a function with no side effects and no state. Functional programming languages generally embrace purity for many reasons, such as reasoning about code and avoiding non-obvious dependencies. Some languages, most notably Haskell, even go so far as to allow only pure code; any side effects a program may have (such as performing I/O) are moved to a non-pure runtime, keeping the language itself pure."
Hi folks. I haven't written anything in a long time but now I have interesting topic to share.
You probably know that in Java recursion is much slower compare to loops. And It makes sense, because in recursion each time is created some stack frame. Each stack frame require some memory allocation and so on. So when we use recursion all time time during invocation your size of stack frames increasing. Same stuff in C++/C and in C#.
You can check it by writing Fibonacci numbers i.e.
But recently I figure out that in Haskell recursion works faster. And in mostly functional programming languages. Bot of course id depends on algorithm. The main reason is - Compiler is better in optimizing pure functions. He can make optimization more eagerly and aggressive.
"The key concept here is purity: a pure function is a function with no side effects and no state. Functional programming languages generally embrace purity for many reasons, such as reasoning about code and avoiding non-obvious dependencies. Some languages, most notably Haskell, even go so far as to allow only pure code; any side effects a program may have (such as performing I/O) are moved to a non-pure runtime, keeping the language itself pure."
Hi, we often work with JVM tuning.
Correct resource allocation, best performance is very important to each program.
Here is useful command to see all JVM options for tuning:
Correct resource allocation, best performance is very important to each program.
Here is useful command to see all JVM options for tuning:
java -XX:+UnlockDiagnosticVMOptions -XX:+PrintFlagsFinal -version
Why is better always to use custom initial capacity for ArrayList?
So, ArrayList have two main parameters.
First one is capacity which defined by default as 10. Capacity is used to create empty array thus help to optimize list by static creation
And size — is size of actual elements which list contains.
When size of list = capacity — list recreate himself as array with newCapacity.
newCapacity = newCapacity + (oldCapacity >> 1)
Which means each time when your list will be full java will create new array.
That's why for better performance is good to use expected initial capacity.
So, ArrayList have two main parameters.
First one is capacity which defined by default as 10. Capacity is used to create empty array thus help to optimize list by static creation
And size — is size of actual elements which list contains.
When size of list = capacity — list recreate himself as array with newCapacity.
newCapacity = newCapacity + (oldCapacity >> 1)
Which means each time when your list will be full java will create new array.
That's why for better performance is good to use expected initial capacity.