Bug high 'direct path read'

Bug 12530276 - high 'direct path read' waits when buffer pools are not setup [ID 12530276.8]

Bug 12530276  high 'direct path read' waits when buffer pools are not setup

 This note gives a brief overview of bug 12530276. 
 The content was last updated on: 12-JUN-2012
 Click here for details of each of the sections below.

Affects:

Product (Component)	Oracle Server (Rdbms)
Range of versions believed to be affected	Versions >= 11.2 but BELOW 12.1
Versions confirmed as being affected	11.2.0.2
Platforms affected	Generic (all / most platforms affected)

Fixed:

This issue is fixed in

12.1 (Future Release) 11.2.0.3 (Server Patch Set) 11.2.0.2 Bundle Patch 16 for Exadata Database

Symptoms:	Related To:
Performance Affected (General) Waits for "direct path read"	DB_KEEP_CACHE_SIZE

Description

While detemining whether (being) scanned objects should be cached or direct read,Current code treats all 'keep objects' as large objects when 'keep pool'
is not configured. This results in direct read of objects created with
'BUFFER_POOL KEEP' clause, even though they are small enough to be cached
in default pool. 
 
Workaround
Configure keep pool for keep objects db_keep_cache_size