BrainyCP

Сервер работает шустро. Но, установил WP, установил Elementor и через время заходя на страницу плагины - идет долгая загрузка и через раз ошибка 504.
При первой загрузке сайта - некоторые элементы не показывается из-за 503 ошибки. При повторной загрузке норм.
Подскажите. Nginx Apache удалял и ставил заново - нифига. 2 ядра и 4 гб Памяти выделил.

Пример на одном из сайтов
[Sun Mar 17 12:41:11.917661 2019] [proxy_fcgi:error] [pid 67321:tid 140542318991104] [client 35.175.205.111:58106] AH01071: Got error 'PHP message: PHP Fatal error: Uncaught Error: Call to undefined function get_header() in /wp-content/themes/twentyfifteen/index.php:17\nStack trace:\n#0 {main}\n thrown in /wp-content/themes/twentyfifteen/index.php on line 17', referer: http://sucuri.net
[Sun Mar 17 12:41:11.977281 2019] [autoindex:error] [pid 67323:tid 140541983381248] [client 35.175.205.111:58108] AH01276: Cannot serve directory /wp-includes/css/: No matching DirectoryIndex (index.php,index.html,index.htm) found, and server-generated directory index forbidden by Options directive
[Sun Mar 17 18:27:42.980657 2019] [proxy_fcgi:error] [pid 48821:tid 140318326322944] [client 37.131.193.16:55374] AH01067: Failed to read FastCGI header, referer:/wp-admin/post.php?post=65&action=elementor
[Sun Mar 17 18:27:42.987577 2019] [proxy_fcgi:error] [pid 48821:tid 140318326322944] (104)Connection reset by peer: [client 37.131.193.16:55374] AH01075: Error dispatching request to : , referer: /wp-admin/post.php?post=65&action=elementor
[Sun Mar 17 18:27:46.533523 2019] [proxy_fcgi:error] [pid 49307:tid 140318376679168] [client 37.131.193.16:55378] AH01067: Failed to read FastCGI header, referer: /wp-admin/post.php?post=65&action=elementor
[Sun Mar 17 18:27:46.533568 2019] [proxy_fcgi:error] [pid 49307:tid 140318376679168] (104)Connection reset by peer: [client 37.131.193.16:55378] AH01075: Error dispatching request to : , referer: /wp-admin/post.php?post=65&action=elementor
[Sun Mar 17 18:27:57.117609 2019] [proxy_fcgi:error] [pid 50221:tid 140318739322624] [client 37.131.193.16:55418] AH01067: Failed to read FastCGI header, referer: /wp-admin/
[Sun Mar 17 18:27:57.117655 2019] [proxy_fcgi:error] [pid 50221:tid 140318739322624] (104)Connection reset by peer: [client 37.131.193.16:55418] AH01075: Error dispatching request to : , referer: /wp-admin/
[Mon Mar 18 11:31:43.441907 2019] [proxy_fcgi:error] [pid 4466:tid 140348860856064] (70007)The timeout specified has expired: [client 37.131.193.167:33244] AH01075: Error dispatching request to : (polling), referer: /wp-admin/update.php?action=upload-plugin

так он же вам пишет
PHP Fatal error: Uncaught Error: Call to undefined function get_header() in /wp-content/themes/twentyfifteen/index.php:17

Это просто одна из ошибок, которая не относится к серверу. Другие посмотрите пожалуйста.

[Mon Mar 18 11:31:43.441907 2019] [proxy_fcgi:error] [pid 4466:tid 140348860856064] (70007)The timeout specified has expired: [client 37.131.193.167:33244] AH01075: Error dispatching request to : (polling), referer: /wp-admin/update.php?action=upload-plugin

Вот например. Перехожу на страницу обновления плагинов. И долго грузит, минуту, и может в 504 выкинуть.

Если буде возможность как нибудь гляньте пожалуйста)

в конфиге сайта посмотрите значение
conn_limit
попробуйте увеличить его в два раза, потом
systemctl restart nginx

Буду благодарен если подскажете где найти этот conn_limit

На всех WP сайтах, вот такая фигня:

[Tue Mar 26 23:55:19.396014 2019] [proxy_fcgi:error] [pid 3696] (70007)The timeout specified has expired: [client 178.213.202.156:44300] AH01075: Error dispatching request to : (polling)
[Tue Mar 26 23:55:23.534746 2019] [proxy_fcgi:error] [pid 125333] (70007)The timeout specified has expired: [client 178.213.202.156:44306] AH01075: Error dispatching request to : (polling)
[Tue Mar 26 23:57:05.975632 2019] [proxy_fcgi:error] [pid 8293] (70007)The timeout specified has expired: [client 178.213.202.156:44474] AH01075: Error dispatching request to : (polling), referer: /wp-admin/plugin-install.php
[Tue Mar 26 23:58:49.762779 2019] [proxy_fcgi:error] [pid 7407] (70007)The timeout specified has expired: [client 178.213.202.156:44596] AH01075: Error dispatching request to : (polling), referer: /wp-admin/plugin-install.php
[Wed Mar 27 00:00:04.447853 2019] [proxy_fcgi:error] [pid 7407] (70007)The timeout specified has expired: [client 178.213.202.156:44696] AH01075: Error dispatching request to : (polling), referer: /wp-admin/update.php?action=upload-plugin
[Wed Mar 27 00:38:08.611463 2019] [proxy_fcgi:error] [pid 8293] [client 178.213.202.156:48300] AH01071: Got error 'PHP message: PHP Warning: Invalid argument supplied for foreach() in /wp-includes/class-wp-list-util.php on line 150\n', referer:/wp-admin/post.php?post=94&action=elementor
[Fri Mar 29 13:48:30.789355 2019] [proxy_fcgi:error] [pid 4448:tid 139683468076800] (70007)The timeout specified has expired: [client 37.120.129.106:34716] AH01075: Error dispatching request to : (polling), referer:/wp-admin/
[Fri Mar 29 13:50:28.821058 2019] [proxy_fcgi:error] [pid 4451:tid 139683401033472] (70007)The timeout specified has expired: [client 37.120.129.106:34878] AH01075: Error dispatching request to : (polling), referer:/wp-admin/plugin-install.php
[Fri Mar 29 13:51:59.889915 2019] [proxy_fcgi:error] [pid 4451:tid 139683493254912] (70007)The timeout specified has expired: [client 37.120.129.106:34990] AH01075: Error dispatching request to : (polling), referer:/wp-admin/plugin-install.php
[Fri Mar 29 13:53:39.517729 2019] [proxy_fcgi:error] [pid 4451:tid 139683325499136] (70007)The timeout specified has expired: [client 193.176.87.122:35098] AH01075: Error dispatching request to : (polling), referer:/wp-admin/plugin-install.php
[Fri Mar 29 13:55:19.696442 2019] [proxy_fcgi:error] [pid 4450:tid 139683735959296] (70007)The timeout specified has expired: [client 193.176.87.122:35242] AH01075: Error dispatching request to : (polling), referer: /wp-admin/plugin-install.php
[Fri Mar 29 13:56:28.690275 2019] [proxy_fcgi:error] [pid 4450:tid 139683744352000] (70007)The timeout specified has expired: [client 193.176.87.122:35400] AH01075: Error dispatching request to : (polling), referer: /wp-admin/plugin-install.php

Вообщем такая хрнеь только после установки плагина Elementor.
Но это важный плагин, на нем все сайты делаю.
До этого было 2 хостера разных. Такой проблемы не было. Куда можно копать?

какая связка стоит?