128 Bucket FAILS in vmstat

[wishmaster]

Hi, all!

I actively use jails with VIMAGE. All works fine but there is one thing which confuse me. This is vmstat output.

vmstat -z:

16 Bucket:               76,      0,      32,      68,      62,   0,   0
32 Bucket:              140,      0,      24,      32,      46,   0,   0
64 Bucket:              268,      0,      25,      45,     117,   0,   0
128 Bucket:             524,      0,      72,     110,    1523, 413,   0

uptime:
13:55  up 23:11, 1 user, load averages: 0,1 0,3 0,2

uname -a
FreeBSD sirius.XXX.com 9.2-STABLE FreeBSD 9.2-STABLE #0: Wed Oct 23 07:20:29 EEST 2013     sirius at sirius.XXX.com:/usr/obj/usr/src/sys/MY6  i386

There are about 500 FAILS of "128 Bucket" per-day. Sometime more. In jails there are web apps mostly (nginx+php). 
What is this? Memory leaks?

Gxxgle has not clarified me of this question.

Thanks!