system slowdown - vnode related

[Masachika ISHIZUKA]

  Hi, this is ishizuka at ish.org.

  I posted problem report of http://www.freebsd.org/cgi/query-pr.cgi?pr=52425.
I think this is the same problem.
  Although it was described to fix this problem in 4.5R as
http://www.freebsd.org/releases/4.5R/relnotes-i386.html#KERNEL,
I tested 4.5R and the system was hanged up. (As sysctl is not responded
in 4.5R when system hanged up, I can not determine that the 4.5R has the
same problem or not.)