search for: htb_cls_array

This patch changes HTB''s class storage from hash+lists to a two-level linear array, so it can do constant time (O(1)) class lookup by classid. It improves scalability for large number of classes. Without the patch, ~14k htb classes can starve a Xeon-3.2 at only 15kpps, using most of it''s cycles traversing lists in htb_find(). The patch eliminates this problem, and has a