User Guide

6-64 Ampex 1308911-02
Model No.
Running Head
dd2_write_perf DD-2 Utilities Manual Pages
sample_rate Integer that specifies sample rate for displaying write calls. If the
sample rate is 1, every write is displayed. If the sample rate is 10,
every tenth write is displayed.
ENVIRONMENT
The $TAPE environment variable specifies the tape device to use if the
-f <device_special_file> option is omitted.
EXIT STATUS
The dd2 utilities use the following exit status codes, and may also produce output to -stdout
on success:
0 Operation succeeded.
nonzero Operation failed.
A nonzero return value describes the error encountered error during processing (see “Exit
Status” on page 6-5).
EXAMPLES
Run dd2_write_perf with a transfer_size of 1MB, a count of 100, and a sample_rate of 1.
dd2_write_perf -perf :1048576:100:1:
The display might look like this:
Instance Cumulative
Transfer write time Bytes/Sec write time Bytes/Sec
0 4.976085 02019373 4.976085 02019373
1 0.532695 18863657 5.508780 03648203
2 0.532974 18853782 6.041754 04989565
3 0.533401 18838689 6.575155 06113058
4 0.556299 18063264 7.131454 07045250
5 0.557867 18012494 7.689321 07840933
6 0.558687 17986056 8.248008 08528123
7 1.735187 05791062 9.983195 08052392
8 0.662090 15177054 10.645285 08495515