IBM Support

Unloading filepath kernel extension to release kernel heap memory on AIX

Troubleshooting


Problem

The Tivoli Storage Manager AIX client Journal-based backup uses a kernel extension to monitor file system changes.

Symptom

The "filepath" kernel extension used by Journal-based backup on AIX to monitor file system change activities allocates kernel heap memory for each file accessed on the system and keeps that memory until the system is rebooted
On systems with many files this memory consumption
can cause the system to become very slow.
Even stopping the dsmc and the tsmjbbd process memory will not be released until an AIX reboot is performed.

Environment

AIX

Diagnosing The Problem

To monitor the memory usage in detail, download latest "perfpmr.sh" script for your AIX O/S from IBM support here and read the README:

ftp://ftp.software.ibm.com/aix/tools/perftools/perfpmr



Contact AIX technical support for further info about "perfpmr" usage.

Examining "memdetails" output it is possible to see that "misc kernel heap" is a major contributor.
Example:


============================================================== ===
Detailed Memory Components | Pages | Megabytes
---------------------------------------------------------|----------------|-----------------------
Light Weight Trace memory | 61432 | 239.96
LVM Memory | 77024 | 300.87
Total Kernel Heap memory | 4330527 | 16916.12
FS2 total non-file memory | 1075016 | 4199.28
metadata_cache | 333576 | 1303.03
inode_cache | 737280 | 2880.00
fs bufstructs | 2076 | 8.10
misc jfs2 | 2084 | 8.14
misc kernel heap | 3255511 | 12716.83

...

Resolving The Problem

In order to release kernel memory, avoiding system reboot, the "filepath" driver can be unloaded.

Follow these steps to perform this activity:


1) Stop the tsmjbbd daemon
2) Stop the tsm client process
3) Execute the following command from an AIX command line prompt:

/opt/filepath/fpunloaddrv.sh

4) Start the Tivoli Journal Based Daemon via "rc.tsmjbb" script

The unload MUST be performed only after having stopped the Tivoli Storage Manager client and journaling backup processes,

[{"Product":{"code":"SSGSG7","label":"Tivoli Storage Manager"},"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Component":"Client","Platform":[{"code":"PF002","label":"AIX"}],"Version":"All Supported Versions","Edition":"","Line of Business":{"code":"LOB26","label":"Storage"}}]

Document Information

Modified date:
17 June 2018

UID

swg21672143