APAR status
Closed as program error.
Error description
When the environment variable IFX_LARGE_PAGES is defined together with the RESIDENT onconfig parameter to enable the large memory pages feature, the creation of shared memory segments is generally a fast activity due to the lower OS resource overhead. When additional segments are required, following startup of the IDS server, they should also be added using the large pages feature. However the ability to use large pages is dependent both on the OS platform and the method by which the new segment is added. When using the onmode -a command to manually add a segment the operation should be fast. When the segment is added automatically due to the memory requirements of a thread then there may be problems: - On Linux it may not be possible to add the new segment. Versions of IDS with a fix for APAR IC86077 will fallback to using normal pages. - On AIX the request to create the new segment will not use large pages due to insufficient privileges of the oninit process. The OS will allocate the shared memory using a standard page size which for large segment sizes can take some time. For example: 14:42:45 Requested shared memory segment size rounded from 30000000KB to 30146560KB 14:42:45 Shared memory segment will use large pages if available. 14:43:39 Dynamically allocated new virtual shared memory segment (size 30146560KB) 14:43:39 Memory sizes:resident:67108864 KB, virtual:214172736 KB, no SHMTOTAL limit The operation to create the new segment took 54 seconds during which time requests to allocate or release memory may be blocked. This can delay user activity.
Local fix
On AIX the delay of adding new segments may be reduced by using a 64 KB page size for shared memory pages instead of the default 4 KB. This may be achieved by setting the environment variable LDR_CNTRL="SHMPSIZE=64K" prior to starting oninit.
Problem summary
**************************************************************** * USERS AFFECTED: * * All Users, * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Update to IDS-11.70.xC8 * ****************************************************************
Problem conclusion
Problem Fixed In IDS-11.70.xC8
Temporary fix
Comments
APAR Information
APAR number
IC90889
Reported component name
INFORMIX SERVER
Reported component ID
5725A3900
Reported release
B70
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2013-03-15
Closed date
2014-02-26
Last modified date
2024-09-24
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Fixed component name
INFORMIX SERVER
Fixed component ID
5725A3900
Applicable component levels
[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSGU8G","label":"Informix Servers"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"B70","Line of Business":{"code":"LOB10","label":"Data and AI"}}]
Document Information
Modified date:
24 September 2024