Welcome to LWN.net The following subscription-only content has been made available to you by an LWN subscriber. Thousands of subscribers depend on LWN for the best news from the Linux and free software communities. If you enjoy this article, please consider subscribing to LWN. Thank you for visiting LWN.net! The kernel's swap subsystem is a complex and often unloved beast. It is also a critical component in the memory-management subsystem and has a significant impact on the performance of th...