https://github.com/slimsag/darfree

Uses black magic to release memory on Darwin.
https://github.com/slimsag/darfree

2017 black darfree dontuse go golang lower magic memory normal pleasedonotuse seriously than trending usage

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Uses black magic to release memory on Darwin.

• Host: GitHub
• URL: https://github.com/slimsag/darfree
• Owner: slimsag
• Created: 2017-06-13T05:41:50.000Z (over 7 years ago)
• Default Branch: master
• Last Pushed: 2017-06-13T05:42:45.000Z (over 7 years ago)
• Last Synced: 2024-10-30T18:48:35.338Z (3 months ago)
• Topics: 2017, black, darfree, dontuse, go, golang, lower, magic, memory, normal, pleasedonotuse, seriously, than, trending, usage
• Language: Go
• Size: 2.93 KB
• Stars: 2
• Watchers: 4
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

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README

        
# Package darfree uses black magic to release memory on Darwin.

darfree is a package that uses ⚫️ black magic (assembly and runtime monkey

patching) to lower the perceived memory consumption of Go programs on

Darwin / amd64 (Mac OS) systems. Since it is based on page size, the actual

'gains' are dependent upon the program itself. They can be as much as your

largest heap allocation. See cmd/darfree for an example which uses ~500MB

without darfree, and only ~17MB with.

## Background

Go allocates memory in pages, and later advises the operating system that it

may free unneeded memory using madvise(..., MADV_FREE) calls. On Linux, this

system call immediately frees the memory page. However, on Darwin machines

the kernel will decide to retain that memory as part of your program's RSS

(residential set size) until memory pressure by your application or another

running on the system causes the kernel to _truly_ free that memory.

In reality, Darwin does the right thing. Keeping the memory as part of your

program's RSS causes no harm, and actually benefits your program by making

subsequent allocations faster. However, from a user's perspective looking at

their "Activity Monitor" it will look like your application is leaking or

using much more memory than it actually is. That is what darfree solves.

## Beware

I advise you really do not use this package at all, unless you really

understand what is going on and what the trade-offs are. At any point in

time this package may become unmaintained, and may break with future Go

versions.

## Usage

```Go

package main

import _ "github.com/slimsag/darfree"

func main() {

  // ...

}

```