Dell PowerVault MD3000i - Manual (Page 4)

Dell™ PowerVault MD3000 and MD3000i Array Tuning Best Practices
December 2008 – Revision A01 Page 4
1 Audience and Scope
This document is intended to guide MD3000 and MD3000i customers through
the advanced processes behind tuning their storage array to best suit their
individual needs. Presented within are the best practices that must be observed
in performance tuning a first generation firmware (06.XX.XX.XX) and second
generation firmware (07.XX.XX.XX) storage array. For further detail on
determining Firmware Generation of a MD3000 or MD3000i storage array,
please view the Dell™ Users Guide at http://support.dell.com/manuals.
2 Performance Tuning Overview
The challenge of storage performance tuning is to understand and control the
interacting components (listed below) while accurately measuring the application
performance. Because the performance of the storage array accounts for only a
portion of the overall application performance, tuning must be performed taking
into account the input/output (I/O) characteristics of the application and all of the
components involved in the data path, such as the SAS HBA, iSCSI initiator,
network switch and host operating system settings.
With multiple aspects to consider, the task of performance tuning to maximize
performance for even one application can seem formidable. Tuning the system to
maximize performance of multiple applications that may share a single storage
array can seem even more formidable. To reduce the complexity of tuning, Dell™
storage systems feature performance monitoring and flexible tuning controls that
can be accessed through the Modular Disk Storage Manager (MDSM).
2.1 Components That Influence Storage Performance
This white paper provides an overall approach to tuning I/O performance and
also provides specific guidelines for using the storage array tuning controls.
These recommendations begin with an overall analysis of the elements that
determine I/O performance:
• Storage array
• Application software
• Server platform (hardware, operating system, volume managers,
device drivers)
• Network (for MD3000i only)
2.2 Basic Approach to Performance Tuning
The first principles of I/O performance tuning include the following question:
What should be the performance for my system?