3 methods override CacheBackendInterface::garbageCollection()

ApcuBackend::garbageCollection in core/lib/Drupal/Core/Cache/ApcuBackend.php: Performs garbage collection on a cache bin.
NullBackend::garbageCollection in core/lib/Drupal/Core/Cache/NullBackend.php: Performs garbage collection on a cache bin.
PhpBackend::garbageCollection in core/lib/Drupal/Core/Cache/PhpBackend.php: Performs garbage collection on a cache bin.

Buggy or inaccurate documentation? Please file an issue. Need support? Need help programming? Connect with the Drupal community.