Estimating the disk space on the Agent system for historical data

This topic provides guidelines for estimating the disk space that is required for storing the historical data on a managed system. If the Agent is configured to collect data at one second interval, the size of this historical data grows rapidly, which requires additional disk space.

Estimating the disk size for the default agent history configuration

The default configuration is to store the historical data for 49 hours. This default period is specified in the Repository.cfg file that is located at the following path:

• UNIX: $BEST1_HOME/bgs/mgroup/
• Windows: %BEST1_COLLECT_HOME%\bgs\mgroup

Use the following formula to calculate the required disk size (in bytes). The formula is applicable for estimating the disk size on UNIX and Windows systems.

where, 

• Directory structure size: The size of the directory structure. For UNIX, this value is 750000, and for Windows the value is 850,000.
• nIntervals: Number of intervals that depend on the parameters in the Repository.cfg file. You can edit the parameter values to modify the intervals. For more information, see Optimizing the size of the Investigate history.
• nCPUs: Number of CPUs
• nDisks: Number of disks that are recognized by the kernel
• nFileSystems: Number of file systems
• nNetworkInterfaces: Number of network interfaces
• nProcesses: Number of processes in the system process table. The average process size is 400 bytes.
• CommandSize: Average command size that depends on the average size of the command string, which is 256.

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Example
 You want to estimate the disk space for the following Windows system:

• Number of CPUs - 2
• Number of disks - 4
• Number of file systems - 14
• Number of network interfaces - 1
• Number of processes - 240
• Command size - 256
• Number of intervals - 616 

The required disk space will be:

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Estimating the additional disk size for collecting data at one second interval

If you enable data collection at one second interval for specific metric groups, you need the additional disk space because the historical data grows rapidly. You can use the same formula for estimating the additional disk space.

Example
You have configured data collection at one second interval for the following metric groups: Processor Statistics, Disk Statistics, File System Statistics, Network Interface Statistics, Process Statistics

For these metric groups, you want to collect historical data at one second interval for 24 hours. The total number of intervals will be:
3600 * 24 (3600 intervals per hour * number of hours in a day) = 86,400

Calculate the additional disk space required as follows:

Add the additional disk size for all these metrics to calculate the total additional disk space required.

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Optimizing the size of the Investigate history

The default period of storing the Investigate history on the managed system is 48 hours. To optimize the disk space, you can limit the size of the Investigate history data to be retained, which affects the number of intervals and the estimations for calculating the disk space.

The amount of historical data to be retained is determined by the following parameters in the Repository.cfg file:

• Number of 10-second sample intervals
• Number of 5-minute summarized spills
• Number of 15-minute summarized spills

The following Repository.cfg file shows the default interval values for the Investigate history:

The following table explains the syntax in the preceding code example:

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To optimize the Investigate history data to be retained on the Agent computer running on UNIX

1. Log in to the computer where the Agent is installed.

2. Change to the $BEST1_HOME/bgs/mgroup directory:

   cd $BEST1_HOME/bgs/mgroup

3. Run the following command to back up the Repository.cfg file:

   cp Repository.cfg Repository.cfg.sav

4. Open the Repository.cfg file and modify the following parameters:

    # 10 second sampling interval
   # 1 hour of 10 second raw data
   # 8 hours of five minute summarized spills
   # 40 hours of fifteen minute summarized spills
   # HISTORY SAMPLING_INTERVAL = 10
   LENGTH = 60 <-- This value is the number of minutes of 10-second samples.
   SUMMARIZATION
    SUMMARIZATION_INTERVAL = 5
   LENGTH = 480 <-- This value is the number of minutes of 5-minute summarized spills.
   SUMMARIZATION
    SUMMARIZATION_INTERVAL = 15
   LENGTH = 2400 <-- This value is the number of minutes of 15-minute summarized spills.
   END_SUMMARIZATION
    END_SUMMARIZATION
    END_HISTORY
5. Save the changes.

6. Run this command to stop the Capacity Agent.

   $BEST1_HOME/bgs/scripts/best1agent_stop -b $BEST1_HOME

7. Run this command to restart the Capacity Agent.

   $BEST1_HOME/bgs/scripts/best1collect -B $BEST1_HOME -q

   The Agent reads the updated Repository.cfg file and uses the updated summarization interval options.

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To optimize the Investigate history data to be retained on the Agent computer running on Windows

1. Log in to the computer where the Agent is installed.
2. Navigate to the %BEST1_HOME%\bgs\mgroup directory.

3. In a text editor, open the Repository.cfg file, and modify the folloing section:

    # 10 second sampling interval
   # 1 hour of 10 second raw data
   # 8 hours of five minute summarized spills
   # 40 hours of fifteen minute summarized spills
   # HISTORY
    SAMPLING_INTERVAL = 10
   LENGTH = 60 <-- This value is the number of minutes of 10-second samples.
   SUMMARIZATION
    SUMMARIZATION_INTERVAL = 5
   LENGTH = 480 <-- This value is the number of minutes of 5-minute summarized spills.
   SUMMARIZATION
    SUMMARIZATION_INTERVAL = 15
   LENGTH = 2400 <-- This value is the number of minutes of 15-minute summarized spills.
   END_SUMMARIZATION
    END_SUMMARIZATION
    END_HISTORY
4. Save the file.
5. Click Start > Programs > BMC PATROL > Perform > Stop Agent.
6. Click Start > Programs > BMC PATROL > Perform > Collect Data.
7. Restart the Agent to use the updated Repository.cfg file.
   1. In the Collect Data window, double-click Query Information from a collect process. 
   2. In the Agent computer field, specify the Agent computer name, and click Apply. 
      A request to query data is sent to the Agent computer, which restarts the bgsagent process.

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Installing