I use wordpress, nginx, mysql, php-fpm with minimun cost on DigitalOcean and found the memory leak problem. This cause MySQL stop working and my websit goes down.
I also found there are lots child processes of php-fpm. I thought I should consider to increase the memory (use 1 GB) or not. Anyway I don’t want to spent my money for my website as I’m person to check it out only one HaHa if you came across to read this. You are second.
These are I did for fix the memory issue.
Create swap file https://www.digitalocean.com/community/tutorials/how-to-add-swap-on-centos-7 I create 2GB swapfile because my memory has 1 GB . If you have memory more than 1 GB , you should multiply 1.5 of physical memory.
//Check Swap usage
//if no return message, it mean no swap
//create swap file
sudo dd if=/dev/zero of=/swapfile count=2096 bs=1MiB
//change permission read write only
sudo chmod 600 /swapfile
//make a swapfile
//Check Swap usage again
//should return swap size
[root@ake warawich.com]# swapon -s
Filename Type Size Used Priority
/swapfile file 2097148 264 -2
Make the Swap File Permanent
/swapfile swap swap sw 0 0
Then reboot OS
Now, you have memory more but the root cause is php-fpm create lots of child process and consume your memory , so you need to limit php-fpm create child process too.
//change configure as below pm = ondemand pm.max_children = 20 pm.start_servers = 5 pm.process_idle_timeout = 10s pm.max_requests = 100
save and restart php-fpm service
systemctl restart php-fpm
//check memory free root@ake warawich.com]# free -m total used free shared buff/cache available Mem: 990 544 111 12 335 294 Swap: 2047 0 2047
All of these what i did! Please suguest me if what you think or what I miss. Thank you.