User Guide

Ampex 1308911-02 6-63
DD-2 Utilities Manual Pages dd2_write_perf
6.21 dd2_write_perf
NAME
dd2_write_perf - measure overall write performance of device and host.
SYNOPSIS
dd2_write_perf -perf <perf_spec> [ -f <device_special_file> ]
dd2_write_perf -help [ help_type ]
DESCRIPTION
dd2_write_perf calculates the write data rate from host system memory to a SCSI device. It
measures time around each of the write calls and outputs individual write and overall times.
dd2_write_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 in Megabytes.
count Integer that specifies number of transfers of transfer_size.