Nginx Perofrmance is too slow even I did all performance trick - mysql

Question

I have Nginx server , which has these configs (/etc/nginx/nginx.conf)
include /etc/nginx/conf.d/modules/*.conf;
user nobody;
worker_processes auto;
#worker_rlimit_nofile 40000;
worker_rlimit_nofile 65535;
error_log /var/log/nginx/error.log warn;
pid /var/run/nginx.pid;
events {
worker_connections 40000;
use epoll;
multi_accept on;
epoll_events 512;
}
http {
#client_header_timeout 3000;
client_body_timeout 300;
fastcgi_read_timeout 3000;
#client_max_body_size 32m;
#fastcgi_buffers 8 128k;
#fastcgi_buffer_size 128k;
include /etc/nginx/mime.types;
default_type application/octet-stream;
log_format main '$remote_addr - $remote_user [$time_local] "$request" '
'$status $body_bytes_sent "$http_referer" '
'"$http_user_agent" "$http_x_forwarded_for"';
access_log /var/log/nginx/access.log main;
open_file_cache max=200000 inactive=20s;
open_file_cache_valid 30s;
open_file_cache_min_uses 2;
open_file_cache_errors on;
access_log off;
tcp_nodelay on;
log_not_found off;
sendfile on;
tcp_nopush on;
# keepalive_timeout 65;
gzip on;
gzip_static on;
gzip_min_length 10240;
gzip_comp_level 1;
gzip_vary on;
gzip_disable msie6;
gzip_proxied expired no-cache no-store private auth;
gzip_types
# text/html is always compressed by HttpGzipModule
text/css
text/javascript
application/x-javascript
application/json
application/xml
application/rss+xml
application/atom+xml
font/truetype
font/opentype
application/vnd.ms-fontobject
image/svg+xml;
#client_body_timeout 10;
send_timeout 2;
keepalive_timeout 60;
# number of requests client can make over keep-alive -- for testing environment
keepalive_requests 100000;
include /etc/nginx/conf.d/*.conf;
}
I am using cpanel and this is the config of my site
server {
server_name alparslan.qsinav.com www.alparslan.qsinav.com;
listen 80;
set $CPANEL_APACHE_PROXY_IP 213.159.7.72;
listen 443 ssl;
ssl_certificate /var/cpanel/ssl/apache_tls/alparslan.qsinav.com/combined;
ssl_certificate_key /var/cpanel/ssl/apache_tls/alparslan.qsinav.com/combined;
ssl_protocols TLSv1.2 TLSv1.3;
ssl_prefer_server_ciphers on;
ssl_ciphers ALL:!ADH:+HIGH:+MEDIUM:-LOW:-EXP;
location / {
try_files $uri $uri/ /index.php?$query_string;
fastcgi_read_timeout 180;
proxy_http_version 1.1;
proxy_set_header Connection "";
proxy_connect_timeout 120;
proxy_read_timeout 120;
proxy_send_timeout 120;
}
location ~* \.(ico|css|js|gif|jpeg|jpg|png|woff|ttf|otf|svg|woff2|eot)$ {
expires 1d;
access_log off;
add_header Pragma public;
add_header Cache-Control "public, max-age=86400";
}
root /home/qsinav/public_html/alparslan/public;
index index.php index.html;
location = /FPM_50x.html {
root /etc/nginx/ea-nginx/html;
}
include conf.d/server-includes/*.conf;
include conf.d/users/qsinav/*.conf;
include conf.d/users/qsinav/alparslan.qsinav.com/*.conf;
location ~ \.php7?$ {
include conf.d/includes-optional/cpanel-fastcgi.conf;
fastcgi_pass unix:/opt/cpanel/ea-php74/root/usr/var/run/php-fpm/58ea52f18cb33ca4e5a37e3fd6c39780e15caa8c.sock;
error_page 502 503 /FPM_50x.html;
}
include conf.d/includes-optional/cpanel-cgi-location.conf;
include conf.d/includes-optional/cpanel-server-parsed-location.conf;
}
the problem that I have , is when more than 80 users login to my system the system going to be very slow , and then I have this error under nginx log
2020/11/07 14:27:11 [error] 1958#1958: *627 upstream timed out (110:
Connection timed out) while reading response header from upstream,
client: 78.182.232.43, server: domain.qsinav.com, request: "GET /
HTTP/1.1", upstream:
"fastcgi://unix:/opt/cpanel/ea-php74/root/usr/var/run/php-fpm/58ea52f18cb33ca4e5a37e3fd6c39780e15caa8c.sock",
host: "domain.qsinav.com"
then the 503 Connection time out start to appear to the clients .
My server's hardware is High (62 GB For RAM ,10 core for cpu )
as I know the worst server must handle more than 10000 users at same time without any problem and my system can not even handle 80 users ,
so where the problem could be ?