Possible scheduler (SCHED_ULE) bug?

[Jaime Bozza]

> Try adding this or changing these items in lighttpd.conf:
> 
> ## FreeBSD!
> server.event-handler	= "freebsd-kqueue"
> server.network-backend 	= "writev"

Scott,

Lighttpd was already using freebsd-kqueue, but I added the writev network-backend and the problem went away.   With this additional information I was able to track down kern/138999, which seems to be the exact issue I'm having.

The additional information I have (over the PR) is that:
1) Files over 64K cause the problem, not just larger files
2) switching over to SCHED_4BSD eliminates the problem - system no longer locks.  
3) 7.2 amd64 doesn't have the problem - Tested a similar configuration and was not able to duplicate on amd64 at all.

I'm CC'ing the original submitter of the PR to give him an update to see if he had any additional luck.

Jaime