Tag Archives: golang

Golang’s sync.Map internals

Great article on the topic — https://victoriametrics.com/blog/go-sync-map/index.html. The whole series of articles is solid, so please take a look if you are interested. Let me share the most important insights. How it works Internal structure is:

type Map struct {
	mu Mutex
	read atomic.Pointer[readOnly]
	dirty map[any]*entry
	misses int
}

type Map struct {

mu Mutex

read atomic.Pointer[readOnly]

dirty map[any]*entry

misses int

}

Go memory hints

Below hints are related to very hot places of CPU/memory bound programs. And in regular (i/o bound) programs do not make much sense. Stack vs heap Go’s compiler goal is to allocate on the stack as much as possible. As it will reduce the amount of data that needs to be cleaned by the Garbage …

Set github actions for you repo

If you want to run tests/linters against you golang project, place something like the example below in .github/workflows/somename.yml to your project:

name: ci-cd

on:
  push:
    branches:
      - '**'

env:
  GONOSUMDB: "github.com/<your-organization>"
  GOPRIVATE: "github.com/<your-organization>"
jobs:
  ci-cd:
    strategy:
      matrix:
        go-version: [ 1.16.x ]
    runs-on: ubuntu-latest
    steps:
      - name: Install Go
        uses: actions/setup-go@v2
        with:
          go-version: ${{ matrix.go-version }}
      - name: Write .netrc for private go modules
        env:
          NETRC_USER: ${{ secrets.NETRC_USER }}
          NETRC_PASS: ${{ secrets.NETRC_PASS }}
        run: echo "machine github.com login ${{ secrets.NETRC_USER }} password ${{ secrets.NETRC_PASS }}" > $HOME/.netrc
      - name: Checkout the code
        uses: actions/checkout@master
        with:
          fetch-depth: 1
      - name: Run Makefile::ci-cd-check
        run: make ci-cd-check

name: ci-cd

on:

push:

branches:

- '**'

env:

GONOSUMDB: "github.com/<your-organization>"

GOPRIVATE: "github.com/<your-organization>"

jobs:

ci-cd:

strategy:

matrix:

go-version: [ 1.16.x ]

runs-on: ubuntu-latest

steps:

- name: Install Go

uses: actions/setup-go@v2

with:

go-version: ${{ matrix.go-version }}

- name: Write .netrc for private go modules

env:

NETRC_USER: ${{ secrets.NETRC_USER }}

NETRC_PASS: ${{ secrets.NETRC_PASS }}

run: echo "machine github.com login ${{ secrets.NETRC_USER }} password ${{ secrets.NETRC_PASS }}" > $HOME/.netrc

- name: Checkout the code

uses: actions/checkout@master

with:

fetch-depth: 1

- name: Run Makefile::ci-cd-check

run: make ci-cd-check

Good article on that — https://github.com/mvdan/github-actions-golang

Example of using embed in go

Nice article on using go templates with embed introduced in go1.16: https://philipptanlak.com/web-frontends-in-go/. That’s the code:

Go internals

Channels https://youtu.be/KBZlN0izeiY Go scheduler https://youtu.be/YHRO5WQGh0k