CentOS7/Debian10 安裝 Redis5

CentOS7 from PVE6 CT-template
- 因為 EPEL 的 redis 版本只到 3 , 發現透過 IUS repo 可以安裝版本 4 或 5
Debian10 from PVE6 TurnKey CT-template

CentOS7 安裝啟動程序

安裝

yum install -y https://repo.ius.io/ius-release-el7.rpm
yum install redis5

啟動

systemctl enable redis
systemctl start redis

Debian10 安裝啟動程序

安裝

sudo apt update
sudo apt install redis-server

啟動 : 在上面的安裝後就會自動設定啟動程序

Redis 啟動檢查

檢查 redis 服務版本狀態

redis-cli info server

呈現結果如下:

# Server
redis_version:5.0.9
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:977de8e50f63afe8
redis_mode:standalone
os:Linux 3.10.0-1127.13.1.el7.x86_64 x86_64
arch_bits:64
multiplexing_api:epoll
atomicvar_api:atomic-builtin
gcc_version:4.8.5
process_id:1869
run_id:e0ff9930e953b9fd6fcc9cb155402a79751539e8
tcp_port:6379
uptime_in_seconds:50
uptime_in_days:0
hz:10
configured_hz:10
lru_clock:16610448
executable:/usr/bin/redis-server
config_file:/etc/redis.conf

啟動時 redis.log 出現以下需要修正的事項

The TCP backlog setting of 511 cannot be enforced because /proc/sys/net/core/somaxconn is set to the lower value of 128. 修正語法
```
vi /etc/sysctl.conf
```
```
:
net.core.somaxconn=1024
```
overcommit_memory is set to 0! Background save may fail under low memory condition. To fix this issue add 'vm.overcommit_memory = 1' to /etc/sysctl.conf and then reboot or run the command 'sysctl vm.overcommit_memory=1' for this to take effect. 修正語法
```
vi /etc/sysctl.conf
```
```
:
vm.overcommit_memory=1
```
you have Transparent Huge Pages (THP) support enabled in your kernel. This will create latency and memory usage issues with Redis. To fix this issue run the command 'echo never > /sys/kernel/mm/transparent_hugepage/enabled' as root, and add it to your /etc/rc.local in order to retain the setting after a reboot. Redis must be restarted after THP is disabled. 修正語法
```
vi /etc/rc.d/rc.local
```
```
:
echo never > /sys/kernel/mm/transparent_hugepage/enabled
```
```
chmod a+x /etc/rc.d/rc.local
```
重新開機讓設定生效

觀察 redis 服務運作狀態(使用記憶體/連結數..)

redis-cli --stat

顯示訊息大概會如下

------- data ------ --------------------- load -------------------- - child -
keys       mem      clients blocked requests            connections
505        1.35M    1       0       8 (+0)              2
505        1.35M    1       0       9 (+1)              2
505        1.35M    1       0       10 (+1)             2
505        1.35M    1       0       11 (+1)             2
505        1.35M    1       0       12 (+1)             2
522        1.83M    2       0       135 (+123)          3
954        2.87M    2       0       1400 (+1265)        3
961        2.92M    3       0       1486 (+86)          4
961        2.92M    3       0       1487 (+1)           4
961        2.94M    4       0       1530 (+43)          5
961        2.96M    5       0       1573 (+43)          6
961        2.96M    5       0       1574 (+1)           6
963        3.06M    6       0       2120 (+546)         7
1060       3.43M    7       0       2530 (+410)         8
1060       3.43M    7       0       2531 (+1)           8
1060       3.49M    8       0       2583 (+52)          9
1060       3.45M    8       0       2601 (+18)          9
1060       3.45M    8       0       2645 (+44)          9
1060       3.45M    8       0       2689 (+44)          9
1060       3.45M    8       0       2690 (+1)           9

參考應用 : Wordpress Plugin - W3 Total Cache

需要安裝 php-redis 套件

yum install php-redis

Dependencies Resolved

=============================================================================================================================================================================================================================================
 Package                                                      Arch                                              Version                                                          Repository                                             Size
=============================================================================================================================================================================================================================================
Installing:
 php-pecl-redis5                                              x86_64                                            5.3.0-1.el7.remi.7.3                                             remi-php73                                            239 k
Installing for dependencies:
 liblzf                                                       x86_64                                            3.6-7.el7                                                        epel                                                   22 k
 libzstd                                                      x86_64                                            1.4.5-3.el7                                                      epel                                                  331 k
 php-pecl-igbinary                                            x86_64                                            3.1.2-1.el7.remi.7.3                                             remi-php73                                             99 k
 php-pecl-msgpack                                             x86_64                                            2.1.0-1.el7.remi.7.3                                             remi-php73                                             58 k

Transaction Summary
=============================================================================================================================================================================================================================================
Install  1 Package (+4 Dependent packages)

參考網址

memdb, redis, debian, centos