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Sat, 01 Sep 2007

Memory defragmentation.

Christoph Lameter from SGI has posted a patchset aimed to implement memory defragmentation in his SLUB memory allocator.
Main idea of the new version is to find pages, which are in the slab, but are not referenced, to free them and combine into bigger chunks (compound pages).

SLAB/SLUB/SLOB still does not support in-page defragmentation, which was one of the main issues in my network (tree) allocator, which combined any objects close to each other, so that allowed bigger allocations, but not only pages into compound pages (which is can do too). Main feature of the network allocator was the idea, that objects should never be freed on the different CPU than where it was allocated. In SLAB this approach is never used and objects can be freed on different than allocation CPUs which leads to the fragmentation.

/devel/networking/nta :: Link / Comments (0)