Further in-depth understanding can be pursued here: http://linux-mm.org/PageReplacementTesting Linux implements an LRU based page replacement algorithm. Although simple, it is suboptimal for a wide range of important workloads. At the present moment there are a few experimental implementations of advanced replacement algorithms being developed and discussed. This page attempts to detail known LRU deficiencies, along with benchmarks to highlight them. In addition to benchmarks, UMass has a Trace Repository, with CPU/memory, network and I/O traces. This can be useful to unit-test replacement algorithms, free from interference by other parts of the OS. http://linux-mm.org/AdvancedPageReplacement The list head for the LRU list (implementing page replacement) is active_list and inactive_list, as declared in page_alloc.c (this is the so-called Pagecache). Page replacement of the pagecache (which page to discard or pageout) is done in kswapd. As for page reclamation, it involved the swapping out pages from the inactive list. (chap 11 of Mel Gorman's Understanding VM book), implemented by kswapd - based on the LRU list. Effectively, reclamation is a subset of page replacement. Proper defined boundary between the two is not given anywhere, so discussion of its differences is not important. But more important are standard terms like PageCache, PageReplacement Policy etc. Just my personal opinions :-). -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
