User Guide

Ampex 1308911-02 6-35
DD-2 Utilities Manual Pages dd2_read_perf
6.11 dd2_read_perf
NAME
dd2_read_perf - measure overall read performance of device and host.
SYNOPSIS
dd2_read_perf -perf <perf_spec> [ -f <device_special_file> ]
dd2_read_perf -help [ help_type ]
DESCRIPTION
dd2_read_perf calculates the read data rate from a SCSI device to host system memory. It
measures time around each of the read calls and outputs individual read and overall times.
dd2_read_perf is available to all users.
OPTIONS
-f <
device_special_file
>
Specifies the device special file to use for the operation (see Appendix B).
ARGUMENTS
-help [
help_type
]
Displays help on stderr and invalidates all other options, cancelling any other actions. Valid
keywords for the optional help_type specification are: stdout, revision, and v_revision.
-perf <
perf_spec>
Specifies the parameters for the read performance test. You must provide a -perf <perf_spec>
argument except when using the -help argument.
The -perf <perf_spec> argument comprises a three-element specification ordered as follows:
-perf :transfer_size:count:sample_rate:. Each element must be delineated by colons and
included in the specification. Valid parameters for the elements are described below.
transfer_size Integer that specifies the transfer size Megabytes.
count Integer that specifies the number of transfers of transfer_size.