Redis cache very slow on Magento 2.4.6

Question

I had a considerable increase in cache growth quickly and my Redis cache slowed down. Adobe recommended to enabled L2 cache.

What's it and how to enable it?

Answer 1

L2 cache is a cache using the CPU's cores. But it is still the Redis you know.

To enable it, you need to configure your Stale cache options like below or your env.php:

'cache' => [
    'frontend' => [
        'default' => [
            'backend' => '\\Magento\\Framework\\Cache\\Backend\\RemoteSynchronizedCache',
            'backend_options' => [
                'remote_backend' => '\\Magento\\Framework\\Cache\\Backend\\Redis',
                'remote_backend_options' => [
                    'persistent' => 0,
                    'server' => 'localhost',
                    'database' => '0',
                    'port' => '6379',
                    'password' => '',
                    'compress_data' => '1',
                ],
                'local_backend' => 'Cm_Cache_Backend_File',
                'local_backend_options' => [
                    'cache_dir' => '/dev/shm/'
                ],
                'use_stale_cache' => false,
            ],
            'frontend_options' => [
                'write_control' => false,
            ],
        ],
         'stale_cache_enabled' => [
            'backend' => '\\Magento\\Framework\\Cache\\Backend\\RemoteSynchronizedCache',
            'backend_options' => [
                'remote_backend' => '\\Magento\\Framework\\Cache\\Backend\\Redis',
                'remote_backend_options' => [
                    'persistent' => 0,
                    'server' => 'localhost',
                    'database' => '0',
                    'port' => '6379',
                    'password' => '',
                    'compress_data' => '1',
                ],
                'local_backend' => 'Cm_Cache_Backend_File',
                'local_backend_options' => [
                    'cache_dir' => '/dev/shm/'
                ],
                'use_stale_cache' => true,
            ],
            'frontend_options' => [
                'write_control' => false,
            ],
        ]
    ],
    'type' => [
        'default' => ['frontend' => 'default'],
        'layout' => ['frontend' => 'stale_cache_enabled'],
        'block_html' => ['frontend' => 'stale_cache_enabled'],
        'reflection' => ['frontend' => 'stale_cache_enabled'],
        'config_integration' => ['frontend' => 'stale_cache_enabled'],
        'config_integration_api' => ['frontend' => 'stale_cache_enabled'],
        'full_page' => ['frontend' => 'stale_cache_enabled'],
        'translate' => ['frontend' => 'stale_cache_enabled']
    ],
],

Take a look at the Redis preload and parallel features. If you need to validate the changes, you can run these commands:

redis-cli ping;
redis-cli monitor;