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How to Identify a Disk Performance Bottleneck Using the Microsoft Server Performance Advisor (SPA) Tool

Clint Huffman

Applies To

Summary

This How-To shows how to use the Microsoft Server Performance Advisor (SPA) tool to identify which processes and files may be causing a disk subsystem performance bottleneck on Windows Server 2003.

Contents

Objectives

In this module, you will learn to do the following:

Overview

Microsoft Performance Monitor (perfmon) can gather performance counter data and Event Tracing for Windows (ETW) data, but it requires manual intervention to do the analysis. This is where the Microsoft Server Performance Advisor (SPA) picks up. The Microsoft Server Performance Advisor (SPA) tool collects performance data in the same manner as Performance Monitor. In addition, it analyzes the data and generates a detailed report on its findings.

Here is the disk related section of the SPA report:

In this how to article, we will use the SPA tool on a Windows 2003 Server to identify a disk subsystem bottleneck, identify which processes are causing the highest disk usage, identify which files are causing the highest disk usage, and determine the data pattern (read/write bytes and I/O’s) of the disk usage.

Download

You can download the Microsoft Service Performance Advisor (SPA) from the following location: http://www.microsoft.com/downloads/details.aspx?FamilyID=09115420-8c9d-46b9-a9a5-9bffcd237da2&DisplayLang=en

Summary of Steps

Here is a summary of steps:

Step 1. Run and Configure the Microsoft Server Performance Advisor (SPA) Tool

In order for the SPA tool to properly diagnose a performance problem, it must collect performance data from the computer when the problem is occurring.
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If you are not familiar with SPA, then consider taking the quick tour of the SPA tool by clicking “Quick Tour”. Otherwise, continue to the next step. The data collected by Server Performance Advisor and the reports it can generate are specified by data collector groups. Data collector groups enable collection of data that is relevant to the server role of the computer, and when you install Server Performance Advisor, it automatically detects the server roles currently configured for the computer. When a role matches a data collector group included with Server Performance Advisor, that data collector group is installed automatically. You can also create your own data collector groups.

In this case, we are only interested in disk subsystem analysis which is provided in the “System Overview” data collector group.

Note: Not all data collector groups analyze data on the disk subsystem.

The next steps are to first try to make the process taking up the most disk I/O more efficient. After the process is made as efficient as possible, then consider additional hardware to make the physical disk faster for this kind of disk I/O. For example, if high write I/O is the problem, then consider RAID0+1 because RAID5 has a 4 to 1 hit ratio for write operations. For more information on RAID type considerations, see the “RAID Type Considerations” below.

Disk optimization is large subject on its own and beyond the scope of this document. In this case, Index Server was misconfigured to index its own catalogs, so changing its catalog settings would make it more efficient.

Conclusion

The Microsoft Server Performance Advisor (SPA) tool is very good at showing which files and processes are causing the most disk I/O.