On Mon, Aug 08, 2011 at 10:31:49PM +0800, Peter Zijlstra wrote: > On Mon, 2011-08-08 at 22:11 +0800, Wu Fengguang wrote: > > It's actually dead code because (origin < limit) should never happen. > > I feel so good being able to drop 5 more lines of code :) > > OK, but that leaves me trying to figure out what origin is, and why its > 4 * thresh. origin is where the control line crosses the X axis (in both the global/bdi setpoint cases). "4 * thresh" is merely something larger than max(dirty, thresh) that yields reasonably gentle slope. The more slope, the larger "gravity" to bring the dirty pages back to the setpoint. > I'm having a horrible time understanding this stuff. Sorry for that. Do you have more questions? Thanks, Fengguang -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>