This document describes how to plan for and measure Input Output Operations per
second (IOPs) when commissioning disk storage to store CommServe Database.
CommServe database volume stores Microsoft SQL database that acts as a central
repository for CommCell wide configuration information. Since nearly every operation
depends on this central critical resource, it is recommended that this volume be
on a fast disk for speedy overall performance.
The following section explains the use of Iometer which is a widely used
industry standard tool for measuring IOPs. Using IOPs rating provides a standard and simplified
way to commission storage without having to understand and use proprietary tools.
Ensure to run the Iometer test on the complete raw
disk.
If you wish to run the Iometer on a volume which has the data,
then make sure to copy the data on a different location before
performing the test. This is to avoid the data loss issue. Once the test
is complete you can copy back the data to old location.
3.
Stop all the services on the CommServe on which the
IOPS need to be tested.
Perform the following steps to stop the
services:
Click the Start button on the Windows task bar and then
click All Programs.
Navigate to bull | Calypso
and click Service Control Manager.
Right-click All Services and click Stop to stop
all services.
4.
Copy all the data from the volume that needs to be
tested to a temporary folder.
Make sure that permission on the
files/folders are also copied.
Worker thread is an entity that runs the test defined under Access Specification
Tab of IoMeter UI. Multiple worker threads run the tests in parallel to test
concurrent performance.
Use the following steps to run Iometer using single worker thread:
6.
Right-click Iometer and click Run as Administrator.
7.
The Iometer dialog box will appear.
8.
Click on the name of the computer available in the Topology
panel on the left side of the window.
The available disk drives will appear
in the Disk Targets tab.
IoMeter, on startup, creates one Manager with multiple worker threads.
Leave one worker thread and delete remaining worker threads by selecting
the worker thread and clicking the Disconnect Selected Worker or
Manager button.
It is recommended to run Iometer on the physical disk that
represents the storage volume for which IOPs need to be measured.
Iometer will allow physical disks to be selected only when there
are no volumes on the disk.
9.
In the Disk Targets tab, select a disk to use in the test.
Values for Maximum Disk Size and Starting Disk Sector
should be set to default, that is 0, to test the complete disk.
If running the test on a volume, Iometer needs to
prepare the volume. It creates a file named
iobw.tst file as part of this preparation phase and runs read/write
tests on this file.
In the figure, blue disk icon represent
physical drives which has no partitions on them.
In the figure, PHYSICALDRIVE:2 is the disk selected
for the test.
