Hitachi Dynamic Link Manager Software Users Guide for Linux

Table A-1 Examples of Linux Command Execution Times
Linux
commands
Time
Example 1
#1
Example 2
#2
Before HDLM
installation
After HDLM
installation
Before HDLM
installation
After HDLM
installation
lvmdiskscan 6.1 sec 19.6 sec 3.8 sec 10.6 sec
pvscan 2.6 sec 12.6 sec 1.5 sec 5.2 sec
# 1
CPU: Pentium III 1.4 GHz x 2
Memory: 1 GB
Connection between host and storage systems: 64 LU x 2 paths (total
128 paths)
# 2
CPU: Xeon 2.0GHz x 2
Memory: 2 GB
Connection between host and storage systems: 64 LU x 2 paths (total
128 paths)
Notes on the iostat Command
If an HDLM device is not specified for the iostat command, the HDLM device
will not be displayed. Information about an HDLM device is displayed only
when the HDLM device is specified for the iostat command (in such case as
iostat -x /dev/sddlmaa). The information (CPU or I/O statistics) displayed
for the HDLM device is always 0, and the actual value is displayed for each
SCSI device that conforms to the HDLM device.
If you are going to obtain information about an HDLM device, perform
calculations by using the value of a SCSI device that conforms to the HDLM
device. The following is an example of executing the iostat command.
Figure A-2 Example of Executing the iostat Command
Notes on Linux Commands and Files
A-3
Hitachi Dynamic Link Manager (for Linux®) User Guide