Installation guide

−r
Specifies a read-only test. This test reads from the specified
partitions. Specify the −n flag to run this test on the block
special file.
This test is useful for generating system I/O activity. Because
it is a read-only test, you can run more than one instance of
the exerciser on the same disk.
−w
Specifies a write test. This test verifies that data can be
written to the disk and can be read back to verify the data.
Seeks are also done as part of this test. This test provides the
most comprehensive coverage of disk transfer functions
because it uses reads, writes, and seeks. This test also
combines sequential and random access patterns.
This test performs the following operations using a range of
transfer sizes; a single transfer size is used if the −F attribute
is specified:
• Sequentially writes the entire test partition, unless the
number of transfers has been specified using the
−num_xfer parameter
• Sequentially reads the test partition
The data read from the disk is examined to verify it. Then, if
random transfer testing has not been disabled (using the −S
attribute), writes are issued to random locations on the
partition. After the random writes are completed, reads are
issued to random locations on the partition. The data read
from random locations is examined to verify it.
The following flags modify the behavior of the test:
−F
Performs fixed size transfers. If this flag is not specified,
transfers are done using random sizes. This flag can be used
with the −p, −r, and −w test flags.
−i
Specifies interactive mode. In this mode, you are prompted for
various test parameters. Typical parameters include the
transfer size and the number of transfers. The following
scaling factors are allowed:
• k or K (for kilobyte (1024 * n))
• b or B (block (512 * n))
• m or M (megabyte (1024 * 1024 * n))
For example 10K would specify 10,240 bytes.
F–8 Using the System Exercise Tools