Db2 I/O Test

This test, executed by an internal agent, tracks various statistics pertaining to the inputs and outputs of a DB2 UDB database. The details of the test are provided below:

Target of the test : A DB2 database server

Agent deploying the test : An internal agent

Outputs of the test : One set of results for every database being monitored

Configurable parameters for the test
Parameter Description

Test period

How often should the test be executed

Host

The IP address of the DB2 server

Port
  • The port number through which the DB2 server communicates. The default port is 50000.
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    Measurements made by the test:
    Measurement Description Measurement Unit Interpretation

    Direct read rate:

    Indicates the total number of direct reads by the application per sec. In other words, it the number of read operations that do not use the buffer pool.

    Reads/Sec

    Direct reads are performed in units, the smallest being a 512-byte sector. They are used when:

    • Reading LONG VARCHAR columns
    • Reading LOB (large object) columns
    • Performing a backup

    A high value over a period of time may be indicative of a performance bottleneck.

    Direct write rate:

    Indicates the total number of direct writes by the application per sec. In other words, it is the number of write operations that do not use the buffer pool.

    Writes/Sec

    Direct writes are performed in units, the smallest being a 512-byte sector. They are used when:

    • Writing LONG VARCHAR columns
    • Writing LOB (large object) columns
    • Performing a restore
    • Performing a load.

    A high value over a period of time may be indicative of a performance bottleneck.

    Buffer pool I/O rate:

    Indicates the rate at which the buffer pool I/O operations are being done in the database.

    IOs/Sec

    In conjunction with the hit ratio statistics, and the characteristics of the applications executing, the I/O load may require adjustment of BUFFPAGE, or applications may require further tuning.