LCache

LCache is a module that applies the tiered caching model of multi-core processors (with local L1 and central L2 caches) to web applications. This allows scaling cache read access independently of network throughput. The current production implementation uses APCu as L1 and the database as L2.

Requirements: PHP 5.6 with APCu 4.0.11+ or PHP 7.0 with APCu 5.x.

Configuration: This module currently obtains database configuration using environment variables which are only present on Pantheon. We will eventually try to obtain configuration in a way friendlier with settings.php. In the mean time, you can set them in $_ENV (see lcache.cache.inc for expected values) before including the cache implementation.

Tuning: This cache system makes writes more expensive to the (great) benefit of reads. This means that it's not good for bins like "cache_form" because they have fairly balanced read versus write behavior.