On Mon, Apr 12, 2010 at 9:09 AM, Nick Piggin <npiggin@xxxxxxx> wrote: >> I think Andrea and Mel and you demonstrated that while defrag is futile in >> theory (we can always fill up all of RAM with dentries and there's no 2MB >> allocation possible), it seems rather usable in practice. > > One problem is that you need to keep a lot more memory free in order > for it to be reasonably effective. Another thing is that the problem > of fragmentation breakdown is not just a one-shot event that fills > memory with pinned objects. It is a slow degredation. > > Especially when you use something like SLUB as the memory allocator > which requires higher order allocations for objects which are pinned > in kernel memory. I guess we'd need to merge the SLUB defragmentation patches to fix that? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>