prompt Latch Section
prompt****************************************************
prompt if miss_ratio or immediate_miss_ratio > 1 then latch
prompt contention exists, decrease LOG_SMALL_ENTRY_MAX_SIZE in init.ora
prompt
set pages 200
set linesize 200
col substr(l.name,1,30) format a30
select substr(l.name,1,30) name,
(misses/(gets+.001))*100 "miss_ratio",
(immediate_misses/(immediate_gets+.001))*100
"immediate_miss_ratio"
from v$latch l, v$latchname ln
where l.latch# = ln.latch#
and (
(misses/(gets+.001))*100 > .2
or
(immediate_misses/(immediate_gets+.001))*100 > .2
)
order by l.name;
Sample Output:
Code: Select all
NAME miss_ratio immediate_miss_ratio
------------------------------ ---------- --------------------
Memory Management Latch 6.66622225 0
slave class create 2.6315097 0