DB2 FOR LUW / DB2FORLUW / A10 - DB2

Using a high NUMDB setting (~100 or higher) may result 
in a hang or trap on DB2 / Linux.  The high setting results in 
the creation of an additional segment for the DBMS memory set 
during instance startup processing (db2start).  The address 
space assigned to the new segment for the db2sysc process at 
this point in time may not be available in the db2wdog 
(watchdog) process.  The watchdog may not then be able to 
function properly, resulting in unpredictable symptoms, 
including errors related to managing FMP processes. 
 
The db2ckpwd process handling authentication may also be 
impacted.  It may trap in sqltinit , resulting in hangs when 
attempting to connect to a database (or attach to an instance) 
with authentication. 
 
This problem may be more common in environments using address 
space layout randomization (ASLR). 
 
To confirm vulnerability, check "db2pd -memsets" whether a new 
segment is created immediately after db2start.  This record 
beginning with "Seg0" directly below the "DBMS" record indicates 
a new segment was added. 
 
Memory Sets: 
Name         Address            Id 
DBMS         0x0000000200000000 1314979889 
  Seg0       0x00002AAACD72A000 1315045427

**************************************************************** 
* USERS AFFECTED:                                              * 
* DB2/Linux systems with a high NUMDB setting                  * 
**************************************************************** 
* PROBLEM DESCRIPTION:                                         * 
* See Error Description                                        * 
**************************************************************** 
* RECOMMENDATION:                                              * 
* Upgrade to DB2 Version 10.1 Fix Pack 5                       * 
****************************************************************

Avoid unnecessarily large settings for the NUMDB database 
manager configuration parameter

Problem first fixed in DB2 Version 10.1 Fix Pack 5

see Local Fix

Date  - problem reported    :
Date  - problem closed      :
Date  - last modified       :

03.04.2014
16.07.2015
16.07.2015