This was really bugging me, so I hacked out
the test case for the attach failure.

Hoses 2.6.29.1 100% every time.  Run it like this:

tcbm_att
tcbm_att -
tcbm_att -
tcbm_att -

It will break on the last iteration with ENOMEM
and ENOMEM is all any shmget() or shmat() call
gets forever more.

After removing the segments this appears:

HugePages_Total:    2048
HugePages_Free:     2048
HugePages_Rsvd:     1280
HugePages_Surp:        0

Even though no segments show in 'ipcs'.