The PDO cache adapter allows to configure the connection in several ways: using a PHP PDO object, a Doctrine DBAL Connection, or a Data Source Name (DSN). In Symfony 4.4, it will also be possible to use a URL DSN. This means for example that you can reuse the DATABASE_URL value if you want to:

Added new marshallers¶

In computing science, a marshaller transforms the memory representation of an object to a data format suitable for storage or transmission. In Symfony 4.4 we've added two marshallers to the Cache component.

The first one is TagAwareMarshaller , which optimizes the data storage when using tag-aware cache adapters. This marshaller is enabled automatically so you don't have to do anything.

The second one is DeflateMarshaller , which compresses the contents before caching them to save space (and uncompresses them automatically later, so the entire process is transparent to the user).

This marshaller is not enabled by default because that might break cache pools that are shared between different applications. You can enable it via decoration: