vmstat -z

[n dhert]

in a crash dump, I see in vmcore.txt.7, In a output of vmstat -z

ITEM                     SIZE     LIMIT      USED      FREE  REQUESTS
FAILURES
16 Bucket:                152,        0,      150,        0,
150,        0
32 Bucket:                280,        0,      165,        3,
165,        0
64 Bucket:                536,        0,      154,        0,
154,        3
128 Bucket:              1048,        0,     1115,        1,     1115,
1811

Failures '128 Bucket': 1811. What does this mean?
the man page vmstat does not explain vey much .. man uma neither as
to what 'failures" can mean ...