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Library cache pins are used to manage library cache concurrence. Pinning an object causes the heaps to be loaded into memory (if not already loaded). PINS can be acquired in NULL, SHARE or EXCLUSIVE m...

This event controls the concurrency between clients of the library cache. It acquires a lock on the object handle so that either: One client can prevent other clients from accessing the same object Th...

This latch serializes access to the objects in the library cache. Every time a SQL statement, a PL/SQL block or a stored object (procedure, package, function, trigger) is parsed or executed, this latc...

Often a write to disk. Solutions Consistent Slow Performance Improve I/O Investigate if the application can be changed to perform fewer writes. Abnormal Variations in Performance Investigate potential...

When a request for rows from a table is issued, Oracle may determine through the cost-based optimizer, which index access path is best for finding rows in a table. During this index lookup process, if...

The session is looking for a consistent read version of data but cannot find it in the local cache. The local instance has made a request to other RAC instances for the data and is waiting on its retu...

The session is looking for a consistent read version of data but cannot find it in the local cache. The local instance has made a request to other RAC instances for the data and is waiting on its retu...

This wait, also known as global cache buffer busy prior to Oracle 10g, specifies the time the remote instance locally spends accessing the requested data block. This wait event is very similar to the ...

Problem This will happen if there is no free buffer in the buffer cache for the session to read a new block into. All buffer gets have been suspended. This will frequently occur because DBWR is not wr...

This wait event is experienced whenever the database needs to open a file. Wait time is recorded beginning just prior to when the open request is issued until the time the request is returned, having ...