Compressed caching is the introduction of a new level into the virtual memory hierarchy. Specifically, RAM is used to store both an uncompressed cache of pages in their natural encoding, and a compressed cache of pages in some compressed format. By using RAM to store some number of compressed pages, the effective size of RAM is increased, and so the number of page faults that must be serviced by very slow hard disks is decreased. The main goal is to implement this compressed caching in Linux 2.4 (2.5).
|Tags||Operating System Kernels Linux|
|Operating Systems||POSIX Linux|
Release Notes: Page cache is now supported, which means that pages from page cache as well as swap cache pages are compressed. Manual adaptivity has been fully implemented. This version also supports shared memory again. Clean pages support was added in compressed cache. Many cleanups were made. The code was simplified. Much more code documentation was written, and code stability was improved. Unfortunately, the manual adaptivity does not allow compressed cache to be disabled yet.