Published at LXer:

"Slab defragmentation is mainly an issue if Linux is used as a fileserver and large amounts of dentries, inodes and buffer heads accumulate," Christoph Lameter explained when posting the fifth version of his patchset. He continued,"in some load situations the slabs become very sparsely populated so that a lot of memory is wasted by slabs that only contain one or a few objects. In extreme cases the performance of a machine will become sluggish since we are continually running reclaim. Slab defragmentation adds the capability to recover wasted memory."

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