This note gives a brief overview of bug 7715339.
 The content was last updated on: 27-JUL-2011
 Click here for details of each of the sections below.

Affects:

Product (Component)	Oracle Server (Rdbms)
Range of versions believed to be affected	Versions >= 11.1
Versions confirmed as being affected	11.1.0.7
Platforms affected	Generic (all / most platforms affected)

Fixed:

This issue is fixed in

11.2.0.1 (Base Release)

Description

In 11g there is an intentional delay between allowing failed logon
attempts to retry. For some specific application types this can cause
a problem as the row cache entry is locked for the duration of the
delay . This can lead to excessive row cache lock waits for DC_USERS .

This "fix" allows the logon delay to be disabled in 11.2.0.1 onwards
by setting event 28401 in the init.ora.
eg:
    event="28401 trace name context forever, level 1" # disable logon delay.
This "event" will disable the logon sleep delay system-wide, 
ie. it will affect all user accounts, system-wide, and so should be used
    with extreme caution as it makes the database more vulnerable to
    logon attacks.

Note: 
 One off fixes for this issue for 11.1.0.7 do not need an event set -
 interim patches for 11.1 disable the delay unconditionally.

Work Around:
 Ensure the correct password is used - especially for connection 
 intensive logons

 

References

Bug:7715339 (This link will only work for PUBLISHED bugs)
Note:245840.1 Information on the sections in this article