Environment centos7, memory at least 4G, Gitlab is memory intensive.
GitHub Installation Reference: https://about.gitlab.com/install/
Component Installation Reference: https://docs.gitlab.com/ce/development/architecture.html

install

1. Configure Yum Source
   Use the domestic software mirror station, here use Tsinghua University's open source software mirror station.
   cat /etc/yum.repos.d/tsinghua.repo

   [gitlab-ce]
   name=Gitlab CE Repository
   baseurl=https://mirrors.tuna.tsinghua.edu.cn/gitlab-ce/yum/el$releasever/
   gpgcheck=0
   enabled=1

2. install
   Installation-related dependencies

   yum install curl policycoreutils-python openssh-server

   Then update the package cache and install it

   yum makecache
   yum install gitlab-ce

   When a fox head appears at the end of the installation, the installation is successful.

3. Start Configuration
   directory structure
   /opt/gitlab home directory
   /etc/gitlab/profile directory
   /var/log/gitlab/log directory
   Modify Configuration
   vim /etc/gitlab/gitlab.rb

   external_url 'http://10.10.10.55'#This means that if nginx modifies the port, it must also have a port inside the external_url
   gitlab_rails['time_zone'] = 'Asia/Shanghai'    #time zone
   unicorn['worker_processes'] = 4    #Depending on the number of server CPU cores
   nginx['listen_port'] = 80   #The default Nginx port is 80, which uses the existing Nginx service from gitlab, or of course, the Nginx service you installed.

   After modifying the configuration, it needs to be executed to reload the configuration:

   gitlab-ctl reconfigure

   Gitlab start: gitlab-ctl start
   Gitlab view status: gitlab-ctl status

   run: alertmanager: (pid 28348) 10561s; run: log: (pid 16612) 18335s
   run: gitaly: (pid 28362) 10561s; run: log: (pid 16611) 18335s
   run: gitlab-exporter: (pid 28383) 10560s; run: log: (pid 16617) 18335s
   run: gitlab-workhorse: (pid 28398) 10560s; run: log: (pid 16604) 18335s
   run: grafana: (pid 28407) 10559s; run: log: (pid 16621) 18335s
   run: logrotate: (pid 9348) 3359s; run: log: (pid 16616) 18335s
   run: nginx: (pid 28426) 10559s; run: log: (pid 16613) 18335s
   run: node-exporter: (pid 28510) 10558s; run: log: (pid 16619) 18335s
   run: postgres-exporter: (pid 28516) 10558s; run: log: (pid 16618) 18335s
   run: postgresql: (pid 28523) 10557s; run: log: (pid 16615) 18335s
   run: prometheus: (pid 28532) 10557s; run: log: (pid 16599) 18335s
   run: redis: (pid 28550) 10556s; run: log: (pid 16596) 18335s
   run: redis-exporter: (pid 28554) 10556s; run: log: (pid 16605) 18335s
   run: sidekiq: (pid 28563) 10556s; run: log: (pid 16614) 18335s
   run: unicorn: (pid 28569) 10555s; run: log: (pid 16603) 18335s

   Log in to Gitlab
   
   Gitlab default user root, first login prompt to change password

4. Gitlab structure
   When Gitlab starts, users and directories are created based on the configuration definition, and components that are dependent by default are in the / var/opt/gitlab directory.
   The main components of Gitlab are:
   Nginx, postgresql, redis, unicorn, sidekiq.This can also be seen using the gitlab-ctl status command.
   
   Nginx: web Access Entry
   postgresql: database, or mysql
   redis: caching, distributing tasks
   sidekiq: Background task, mainly responsible for e-mail, from redis
   unicorn:gitlab main process
   gitlab-workhorse: A reverse proxy server that handles requests that are not related to the main process unicorn s
   gitaly: Background service that handles all git calls made by Gitlab
   Sinicization
   1. Prepare the environment
   Prepare to install the Chinese package directory.
   Cd/opt/src/Download

   git clone https://gitlab.com/xhang/gitlab.git

   2. View clone to download the patch version in Chinese

   # cat /opt/src/gitlab/VERSION 
   12.3.5

   3. Stop gitlab

   gitlab-ctl stop

   4. View installed versions:

   head -1 /opt/gitlab/version-manifest.txt
   gitlab-ce 12.4.2

   5. Get the Hanghua Bag:

   cd /opt/src/gitlab
   git diff origin/12.3.5-stable origin/12.3.5-stable-zh > /tmp/12.3.5.diff

   6. Update patches to gitlab:

   # yum -y install patch
   cd /tmp/
   #patch -d /opt/gitlab/embedded/service/gitlab-rails -p1 < 12.3.5.diff

   Execute Install Patch and skip directly if the following problem occurs, i.e. keep returning and skipping.Because the patch pack has some newer patch files, they are not available on gitlab.

   can't find file to patch at input line 5
   Perhaps you used the wrong -p or --strip option?
   The text leading up to this was:
   |diff --git a/app/assets/javascripts/awards_handler.js b/app/assets/javascripts/awards_handler.js
   |index 976d32a..7967edb 100644
   |--- a/app/assets/javascripts/awards_handler.js
   |+++ b/app/assets/javascripts/awards_handler.js

   7. Reload the configuration and start Gitlab:

   gitlab-ctl reconfigure & gitlab-ctl start

   Log back in to Gitlab.