Library Cache Lock
878536Aug 14 2011 — edited Sep 13 2011Hi,
my db version is 11.0.1.7
i have high library cahce lock waits, and problematic sql is SELECT statement.
what may be the cause?
shared_pool_size 1500 MB
session_cached_cursors 20.
Thanks,
{
Top 5 Timed Foreground Events
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Avg
wait % DB
Event Waits Time(s) (ms) time Wait Class
------------------------------ ------------ ----------- ------ ------ ----------
library cache lock 6,193,375 203,610 33 79.9 Concurrenc
DB CPU 12,668 5.0
library cache: mutex X 59,365,758 11,970 0 4.7 Concurrenc
cursor: mutex S 35,166,712 8,079 0 3.2 Concurrenc
control file sequential read 2,208,754 2,646 1 1.0 System I/O
}