Skip to Main Content

SQL & PL/SQL

Announcement

For appeals, questions and feedback about Oracle Forums, please email oracle-forums-moderators_us@oracle.com. Technical questions should be asked in the appropriate category. Thank you!

Ghost SQL

Nikolay SavvinovMar 9 2012 — edited Mar 10 2012
Hi,

One of the databases I'm working with is suffering from massive library cache contention (cursor: pin S, cursor: pin S wait on X, latch free totalling to about 85-90% of database time during 1-2 hour outbursts which happen once every few weeks).

ASH shows that most of these events are linked to sql id which doesn't exist anywhere: V$SQL, V$ACTIVE_SESSION_HISTORY, DBA_HIST_SQLTEXT etc. all showed nothing.

Today, I caught this problem in real time, and found the offending SQL. However, V$SQL is showing very odd figures for it, which explain why the SQL is not seen anywhere in the AWR report.

I wonder if anyone has seen anything like this and has an explanation and/or advice...
SQL_ID	RUNTIME_MEM	SORTS	LOADED_VERSIONS	OPEN_VERSIONS	USERS_OPENING	FETCHES	EXECUTIONS	PX_SERVERS_EXECUTIONS	END_OF_FETCH_COUNT	USERS_EXECUTING	LOADS
b5jgpar3b58xq	0	0	0	1	14	0	0	0	0	1	1
Best regards,
Nikolay
Comments
Locked Post
New comments cannot be posted to this locked post.
Post Details
Locked on Apr 7 2012
Added on Mar 9 2012
3 comments
437 views