Wordpress stucks at peak moments on heavy traffic

Hello there,
First of all i love Hestia. Since now I had no issues but today two of my websites got bigger and wordpress times out at peak moments on heavy traffic. For instance.
On one dedicated server i run only one website. The server Load Average was only at 6, Hestia was not freezed, only the website timed out.

On error log i saw many errors like this one:
unix:/run/php/php7.4-fpm-xxxxx.xxx.sock failed (11: Resource temporarily unavailable) while connecting to upstream, client: xxx

Server Architecture Linux 5.4.0-121-generic x86_64
Web Server nginx/1.23.1
PHP Version 7.4.30 (supports 64-bit values)
PHP SAPI fpm-fcgi
Maximum PHP Input Variables 12000
PHP Timeout 600
PHP Memory Limit 5072M
Maximum Input Timeout 180
Maximum Upload File Size 8M
Maximum PHP Article Size 100M
cURL Version 7.68.0 OpenSSL/1.1.1f
Is SUHOSIN installed? No
Is Imagick library available? Yes
Are pretty permalinks supported? Yes
.htaccess Rules Your .htaccess file contains only WordPress core functionality.

Database extension mysqli
Server version 10.6.8-MariaDB-1:10.6.8+maria~focal
Client version mysqlnd 7.4.30
Database username vasiledale_uvdro
Database host localhost
Database name *
Table prefix *
Database character set utf8mb4
Database collation utf8mb4_unicode_520_ci
Maximum allowed packet size 134217728
Maximum number of connections 1000

What can i increase more?? The webiste is through cloudflare…

What is your server actually doing when it gets stuck?

Let’s not increase everything. Maybe you can solve it with cache, or killing bots or…

The server works. Hestia admin works perfectly, the Load Average was only at 6.

The wordpress site times out, after a time works but loads very slow.

For cache i use WP Super Cache .

Any ideas? Did someone had this issue too?