[PATCH] Double-level file descriptor allocation

[esmith]

Skip Ford wrote:
Here's a DragonFly port of Tim Robbins' FreeBSD port of Niels
Provos' NetBSD file descriptor allocation code.
. ..
          fd    Unpatched      Patched
            1    0.765650     0.781279
         2001    1.148484     0.789092
         4001    1.546935     0.765657
. ..
        48001   12.453618     0.812530
Is there a down-side to this?