Disk capacity planning for historical data

Disk capacity planning for a monitoring agent is a prediction of the amount of disk space to be consumed for each attribute group whose historical data is being collected. Required disk storage is an important factor to consider when you are defining data collection rules and your strategy for historical data collection.

The table in this chapter provides the following information required to calculate disk space for this monitoring agent:

  • Table is the table name as it is displayed in the warehouse database, if the attribute group is configured to be written to the warehouse.
  • Attribute group is the name of the attribute group as it is displayed in the warehouse configuration panel.
  • Bytes per instance (agent) is an estimate of the record length for each row or instance written to the agent disk for historical data collection. This estimate can be used for agent disk space planning purposes.
  • Database bytes per instance (warehouse) is an estimate of the record length for detailed records written to the warehouse database, if the attribute group is configured to be written to the warehouse. Detailed records are those that have been uploaded from the agent for long-term historical data collection. This estimate can be used for warehouse disk space planning purposes.
  • Aggregate bytes per instance (warehouse) is an estimate of the record length for aggregate records written to the warehouse database, if the attribute group is configured to be written to the warehouse. Aggregate records are created by the Summarization agent for attribute groups that have been configured for summarization. This estimate can be used for warehouse disk space planning purposes.

In addition to the information in the tables, you must know the number of instances of data that you plan to collect. An attribute group can have single or multiple instances of data depending on the application environment that is being monitored. For example, if your attribute group is monitoring each processor in your computer and you have a dual processor computer, the number of instances is two.

The following table contains capacity planning information for the data logged by Tape Optimizer.

Table 1. Capacity planning for historical data logged by component
Table Attribute group Bytes per instance (agent) Database bytes per instance (warehouse) Aggregate bytes per instance (warehouse)
KRWPOBJST KRW_PERFORMANCE_OBJECT_STATUS 288 289 326
KRWTMIGDET KRW_TAPE_MIGRATION_DETAIL 282 298 425
KRWVOLCHNL KRW_VOLUME_CHAIN_LIST 114 117 154
KRWVOLDSL KRW_VOLUME_DATASET_LIST 142 143 195
KRWTMDTREP TAPES_PENDING_MIGRATION_DUE_TO_REPLACE 193 198 235
KRWTMIDTER TAPES_PENDING_MIGRATION_DUE_TO_TEMP_ERRORS 188 192 229
KRWTOACT TAPE_OPTIMIZER_ACTIONS 114 112 149
KRWZZAOPAL PRODUCT_ACTION_LOG 204 205 242
KRWCPYSVOL VOLUME_COPY_STATUS
KRWCPYSDS DATA_SET_COPY_STATUS
KRWCPYSJOB JOB_COPY_STATUS

For more information about historical data collection, see the IBM Tivoli Monitoring Administrator’s Guide.