On 05/22/2013 05:03 AM, Kirill A. Shutemov wrote: > On most machines we will have RADIX_TREE_MAP_SHIFT=6. In this case, > on 64-bit system the per-CPU feature overhead is > for preload array: > (30 - 21) * sizeof(void*) = 72 bytes > plus, if the preload array is full > (30 - 21) * sizeof(struct radix_tree_node) = 9 * 560 = 5040 bytes > total: 5112 bytes > > on 32-bit system the per-CPU feature overhead is > for preload array: > (19 - 11) * sizeof(void*) = 32 bytes > plus, if the preload array is full > (19 - 11) * sizeof(struct radix_tree_node) = 8 * 296 = 2368 bytes > total: 2400 bytes > --- > > Is it good enough? Yup, just stick the calculations way down in the commit message. You can put the description that it "eats about 5k more memory per-cpu than existing code" up in the very beginning. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>