[Click] DelayUnqueue 100% cpu

[Mike Scheutzow]

Problem

If I use either the DelayUnqueue or DelayShaper elements with Click 
userlevel, my cpu usage always pegs at 100%.

This problem is present in both 1.6.0 and in the cvs repository 
(checkout on Jan 31, 2008).

Solution

The bug is in the code which decides whether the thread should sleep or 
not. A threshold of 100 milliseconds is way too high.

In elements/standard/delayunqueue.cc and 
elements/standard/delayshaper.cc, I changed:

	usec_to_subsec(100000)
to:
	usec_to_subsec(100)

and everything works much better. Our kernel uses a 1 millisecond tick.


Mike Scheutzow
scheutzow at alcatel-lucent.com