最近、クライアントのサーバーでパフォーマンスの問題が発生し始めました。サーバーでホストされている単一の Web サイトの読み込みが非常に遅いです。これは、カスタム テーマを使用して WordPress で構築されています。インストールされているプラグインは最小限で、パフォーマンスの問題が発生し始めたこの数週間はプラグインが追加されていませんでした。
サーバーには 2 つの CPU と 2 GB のメモリがあります。サーバー スタックは、Ubuntu 20.04 と PHP FPM を搭載した LAMP です。インストールされているソフトウェアはすべて最新の状態に保たれています。
WordPress サイトの実行中は、両方の CPU が常に 80% 以上を使用します。
free -m コマンドは、以下を返します: 合計 1983、使用済み 1734、空き 64、共有 132、バッファ/キャッシュ 184、使用可能 12。
サーバーを再起動すると、これらの問題は一時的に解決されます。
Redis サーバーはオブジェクト キャッシュ用にインストールされています。現在、サーバーまたは WordPress には他のキャッシュ プラグインや最適化プラグインはインストールされていません。
実行してsudo tail -n 10 /var/log/apache2/domain.com_error.log、出力を以下に示しました。
[Mon Feb 20 09:59:27.377362 2023] [proxy_fcgi:error] [pid 310468] [client 104.224.117.81:33410] AH01071: Got error 'PHP message: Predis\\Response\\ServerException: LOADING Redis is loading the dataset in memory in /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php:352\nStack trace:\n#0 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php(320): Predis\\Client->onErrorResponse()\n#1 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php(299): Predis\\Client->executeCommand()\n#2 /var/www/example.com/wp-content/object-cache.php(562): Predis\\Client->__call()\n#3 /var/www/example.com/wp-content/object-cache.php(257): WP_Object_Cache->__construct()\n#4 /var/www/example.com/wp-includes/load.php(730): wp_cache_init()\n#5 /var/www/example.com/wp-settings.php(131): wp_start_object_cache()\n#6 /var/www/example.com/wp-config.php(109): require_once('...')\n#7 /var/www/example.com/wp-load.php(50): require_once('...')\n#8 /var/www/example.com/wp-blog-header.php(13): require_once(...', referer: https://www.example.com/listing/the-tree-corral/
[Mon Feb 20 09:59:28.858978 2023] [proxy_fcgi:error] [pid 310553] [client 157.55.39.219:22656] AH01071: Got error 'PHP message: Predis\\Connection\\ConnectionException: Connection refused [tcp://127.0.0.1:6379] in /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Connection/AbstractConnection.php:132\nStack trace:\n#0 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Connection/StreamConnection.php(109): Predis\\Connection\\AbstractConnection->onConnectionError()\n#1 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Connection/StreamConnection.php(154): Predis\\Connection\\StreamConnection->createStreamSocket()\n#2 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Connection/StreamConnection.php(80): Predis\\Connection\\StreamConnection->tcpStreamInitializer()\n#3 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Connection/AbstractConnection.php(81): Predis\\Connection\\StreamConnection->createResource()\n#4 /var/www/example.com/wp-content...'
[Mon Feb 20 09:59:28.859372 2023] [proxy_fcgi:error] [pid 310553] [client 157.55.39.219:22656] AH01071: Got error 'PHP message: PHP Warning: Undefined variable $image in /var/www/example.com/wp-content/themes/themename/functions.php on line 548'
[Mon Feb 20 09:59:32.089611 2023] [proxy_fcgi:error] [pid 310501] [client 157.55.39.219:24128] AH01071: Got error 'PHP message: Predis\\Response\\ServerException: LOADING Redis is loading the dataset in memory in /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php:352\nStack trace:\n#0 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php(320): Predis\\Client->onErrorResponse()\n#1 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php(299): Predis\\Client->executeCommand()\n#2 /var/www/example.com/wp-content/object-cache.php(562): Predis\\Client->__call()\n#3 /var/www/example.com/wp-content/object-cache.php(257): WP_Object_Cache->__construct()\n#4 /var/www/example.com/wp-includes/load.php(730): wp_cache_init()\n#5 /var/www/example.com/wp-settings.php(131): wp_start_object_cache()\n#6 /var/www/example.com/wp-config.php(109): require_once('...')\n#7 /var/www/example.com/wp-load.php(50): require_once('...')\n#8 /var/www/example.com/wp-blog-header.php(13): require_once(...'
[Mon Feb 20 09:59:32.089919 2023] [proxy_fcgi:error] [pid 310501] [client 157.55.39.219:24128] AH01071: Got error 'PHP message: PHP Warning: Undefined variable $image in /var/www/example.com/wp-content/themes/themename/functions.php on line 548'
[Mon Feb 20 09:59:32.285842 2023] [proxy_fcgi:error] [pid 310279] [client 185.191.171.4:8256] AH01071: Got error 'PHP message: Predis\\Response\\ServerException: LOADING Redis is loading the dataset in memory in /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php:352\nStack trace:\n#0 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php(320): Predis\\Client->onErrorResponse()\n#1 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php(299): Predis\\Client->executeCommand()\n#2 /var/www/example.com/wp-content/object-cache.php(562): Predis\\Client->__call()\n#3 /var/www/example.com/wp-content/object-cache.php(257): WP_Object_Cache->__construct()\n#4 /var/www/example.com/wp-includes/load.php(730): wp_cache_init()\n#5 /var/www/example.com/wp-settings.php(131): wp_start_object_cache()\n#6 /var/www/example.com/wp-config.php(109): require_once('...')\n#7 /var/www/example.com/wp-load.php(50): require_once('...')\n#8 /var/www/example.com/wp-blog-header.php(13): require_once(...'
[Mon Feb 20 09:59:32.286079 2023] [proxy_fcgi:error] [pid 310279] [client 185.191.171.4:8256] AH01071: Got error 'PHP message: PHP Warning: Undefined variable $image in /var/www/example.com/wp-content/themes/themename/functions.php on line 548'
[Mon Feb 20 09:59:32.561144 2023] [proxy_fcgi:error] [pid 309940] [client 185.191.171.19:16376] AH01071: Got error 'PHP message: Predis\\Response\\ServerException: LOADING Redis is loading the dataset in memory in /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php:352\nStack trace:\n#0 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php(320): Predis\\Client->onErrorResponse()\n#1 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php(299): Predis\\Client->executeCommand()\n#2 /var/www/example.com/wp-content/object-cache.php(562): Predis\\Client->__call()\n#3 /var/www/example.com/wp-content/object-cache.php(257): WP_Object_Cache->__construct()\n#4 /var/www/example.com/wp-includes/load.php(730): wp_cache_init()\n#5 /var/www/example.com/wp-settings.php(131): wp_start_object_cache()\n#6 /var/www/example.com/wp-config.php(109): require_once('...')\n#7 /var/www/example.com/wp-load.php(50): require_once('...')\n#8 /var/www/example.com/wp-blog-header.php(13): require_once(...'
[Mon Feb 20 09:59:33.157553 2023] [proxy_fcgi:error] [pid 310553] [client 157.55.39.219:22656] AH01071: Got error 'PHP message: Predis\\Response\\ServerException: LOADING Redis is loading the dataset in memory in /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php:352\nStack trace:\n#0 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php(320): Predis\\Client->onErrorResponse()\n#1 /var/www/example.com/wp-content/plugins/redis-cache/dependencies/predis/predis/src/Client.php(299): Predis\\Client->executeCommand()\n#2 /var/www/example.com/wp-content/object-cache.php(562): Predis\\Client->__call()\n#3 /var/www/example.com/wp-content/object-cache.php(257): WP_Object_Cache->__construct()\n#4 /var/www/example.com/wp-includes/load.php(730): wp_cache_init()\n#5 /var/www/example.com/wp-settings.php(131): wp_start_object_cache()\n#6 /var/www/example.com/wp-config.php(109): require_once('...')\n#7 /var/www/example.com/wp-load.php(50): require_once('...')\n#8 /var/www/example.com/wp-blog-header.php(13): require_once(...'
[Mon Feb 20 09:59:33.157733 2023] [proxy_fcgi:error] [pid 310553] [client 157.55.39.219:22656] AH01071: Got error 'PHP message: PHP Warning: Undefined variable $image in /var/www/example.com/wp-content/themes/themename/functions.php on line 548'
これらの問題に対処する方法について何か提案はありますか?
私は初心者のサーバー管理者ですが、学ぶ意欲があります。