Whether your environment includes a data warehouse or is
set up for conversion of short-term history to delimited flat files,
it is a good idea to set a maximum size for the history files.
Before you begin
Your operating system user ID must have write permission
for this directory.
These agent environment variables are not available
on z/OS®.
About this task
When your configuration includes data roll-off to the Tivoli® Data Warehouse, the size
of the short-term history files is controlled by the amount of data
being collected, the frequency of collection, and the frequency of
roll-off to the data warehouse. Yet, it is possible for the warehouse
proxy agent or data warehouse to become unavailable, which means the
short-term history files can grow unchecked.
Set the KHD_TOTAL_HIST_MAXSIZE
and KHD_HISTSIZE_EVAL_INTERVAL environment variables at every Tivoli Enterprise Monitoring Agent where
historical data is collected or at the Tivoli Enterprise Monitoring Server if
data collection occurs there.
Complete these steps to specify a
size limit for the directory where short-term history files are saved
and how often that this check should take place:
Procedure
- Open the environment file for the agent:
-
In the Manage Tivoli Monitoring
Services window, right-click the component and click Advanced
→ Edit ENV File. (These are the install_dir\TMAITM6\K<pc>ENV files
where <pc> is the two-character product code, such as C:\IBM\ITM\TMAITM6\KNTENV.)
- Change to the install_dir/config directory
and open <pc>.ini in a text editor, where <pc>
is the two-character product code. For example, /opt/IBM/ITM/config/ux.ini
for the UNIX OS agent.
For a list of product codes see "IBM Tivoli product, platform, and component codes" in the IBM Tivoli Monitoring Installation
and Setup Guide.
- Add two new lines to the file, where 5 is
the maximum number of megabytes that the directory where the short-term
history file is located can grow to; and where 900 (15
minutes) is the number of seconds between evaluation of the directory
size:
KHD_TOTAL_HIST_MAXSIZE =5
KHD_HISTSIZE_EVAL_INTERVAL=900
- Save and close the file.
- Recycle the component.
Results
After you set a maximum and the directory limit is reached,
no new records are written to the short-term history files, which
causes gaps to occur in the data collected. However, if the data is
warehoused, the warehouse proxy will trim the short term history files
to contain only the last 24 hours of data. This can allow the agent
to write historical data again; thus, the limit can be reached again
and the process repeats. This process can also cause gaps to appear
in the data.