|
Problem IC78581
|
Status: Closed |
DB2_MEMORY_PROTECT MAY CAUSE SPURIOUS ERRORS |
| product: |
DB2 FOR LUW / DB2FORLUW / 950 - DB2 |
| Problem description: |
Enabling memory protection via the DB2_MEMORY_PROTECT registry
variable may cause the DB2 database engine to incorrectly fail
with spurious memory protection errors.
This type of failure can manifest in many ways, but a common
signature is a DB2 trap file that shows a SIGSEGV trap with an
si_code field of hex 34:
Signal #11 (SIGSEGV): si_addr is <some address>, si_code is
0x00000034
Memory protection is only functional on AIX systems running on
hardware with memory key support (Power 6 and later). Other
platforms are not affected. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* DB2 v9.5 or later on AIX systems with hardware that supports *
* storage keys (Power 6 and later) *
****************************************************************
* PROBLEM DESCRIPTION: *
* Enabling memory protection via the DB2_MEMORY_PROTECT *
* registry variable may cause the DB2 database engine to *
* incorrectly fail with spurious memory protection errors. *
* *
* This type of failure can manifest in many ways, but a common *
* signature is a DB2 trap file that shows a SIGSEGV trap with *
* an si_code field of hex 34: *
* *
* Signal #11 (SIGSEGV): si_addr is <some address>, si_code is *
* 0x00000034 *
* *
* Memory protection is only functional on AIX systems running *
* on hardware with memory key support (Power 6 and later). *
* Other platforms are not affected. *
****************************************************************
* RECOMMENDATION: *
* Do not set the DB2_MEMORY_PROTECT registry variable, or *
* explicitly set it to "NO". *
**************************************************************** |
| Local Fix: |
Do not set the DB2_MEMORY_PROTECT registry variable, or
explicitly set it to "NO". |
| available fix packs: |
DB2 Version 9.5 Fix Pack 9 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 10 for Linux, UNIX, and Windows
|
| Solution |
The DB2_MEMORY_PROTECT registry variable will be ignored in DB2
v9.7 fp5 and later fixpacks while a comprehensive review is
performed. Once the review is complete the function will either
be rehabilitated or formally deprecated.
As of DB2 v9.5 fp9, the registry variable can still be set (and
will remain set if set previous). Regardless of the setting,
however, the DB2 engine will not enable memory protection. |
| Workaround |
Do not set the DB2_MEMORY_PROTECT registry variable, or
explicitly set it to "NO". |
| Comment |
Final resolution of this issue will be documented via APAR,
Technote and/or updates to product documentation as appropriate. |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 08.09.2011
12.03.2012
12.03.2012 |
| Problem solved at the following versions (IBM BugInfos) |
9.5.FP9,
9.7.FP5
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 9.5.0.9
|
 |
