70-270 Windows XP TechNotes - Performance

Index
- Performance
- Memory and processor
-- Task Manager
- Performance Tools
- Disk Defragmenter
- Scheduled Tasks
- Visual Effects

PERFORMANCE

Windows XP has several performance improvements over its predecessor Windows 2000, but it requires some more heavy machinery as well. The following paragraphs describe how to monitor, optimize, and troubleshoot performance on a Windows XP Professional system.

Memory and Processor

The amount of physical memory as well as the type and the number of processors in a Windows XP computer are the most determining factors when it comes to performance. On the Advanced tab of the Performance Options shown below (click the Settings button in the Performance section of the Advanced tab of the System Properties), you can specify how processor time and memory is put to use.

If the Windows XP computer is a regular client, both the Processor Scheduling and Memory Usage option should be set to the default selection Programs. If the computer is used as a ‘server’ i.e. running IIS or a shared application, and it is not used for the usual client software such as email and office applications, it is usually better to change the Processor Scheduling setting to Background services and/or the Memory Usage setting to System Cache.

Memory is something a computer running Windows XP should have plenty of. The minimum recommended amount of RAM is 128 MB or higher. Make that much higher if you are running Microsoft Office or any other memory consuming application. Because the amount of physical memory in a computer is often not sufficient for running large programs simultaneously, Windows XP uses virtual memory. Virtual memory is the RAM in the computer and a large file on the hard disk. This file is referred to as paging file or swap file and is named pagefile.sys on disk. Data is swapped between physical memory and the paging file as needed. Excessive swapping results in a lot of hard disk activity, which can indicate that either the paging file is too small but more often that the computer needs extra physical memory.

You can configure the virtual memory settings by clicking the Change button in the Virtual Memory section of the Advanced tab of the Performance Options. The recommended minimum size of the paging file is 1.5 times the amount of the RAM, and the maximum size 3 times the amount of RAM. For optimal performance, it is recommended that you locate the paging file on another physical disk than the operating system.


Task Manager

On the Performance tab of the Task Manager you can get a quick overview of memory (physical and paging file) and processor usage and availability. You can open the Task Manager by right-clicking on the Task bar and choosing it from the menu or by pressing CTRL-AT-DEL and click the Task Manager button.

On the Task Manager’s Processes tab shown below you can see the current running processes and how much CPU and memory resources each process uses. It also allows you to end a process, change the priority of a process, and set processor affinity.

Ending processes is useful for killing a process that hangs or looks suspicious. If the process has child processes you can select End Process Tree from the right-click menu instead of End Process (or clicking the End Process button). If an applications hangs, you should try to end it using the End Task button on the Applications tab first as it might help to shut down all related processes and child processes as well.

Changing the priority of a process allows you to increase or reduce the share of processor time a process gets. Increasing the priority is rarely done, but if you run a CPU-intensive program (i.e. compiling, rendering, scanning) that runs for several hours you could lower the priority for that process reducing the impact it has on foreground applications. On a dual-processor Windows XP computer, there is an additional option Set Affinity. This allows you to assign a process to one single CPU.


Performance tools

A more advanced method to monitor memory, processor, disk, network, and other activity is using Performance from the Administrative Tools in the control panel. It provides access to two different tools that can be used for measuring performance on local and remote systems:

System Monitor – Allows you to monitor system activity and view the real-time results in graphs or reports. You can also view logged data from Performance Logs and Alerts.

Performance Logs and Alerts – Allows you to monitor system activity and record the results to a log file. Additionally, you can set alerts to notify you when a specified counter's value is above or below a defined threshold. In addition to a binary log-file format, the data can be stored in CSV or tab-separated format; hence can be easily imported in spreadsheets or databases for further analysis and reporting. You write the log data directly to an SQL database. This option is typically only used when collecting data from a large number of clients and servers.

Both tools use performance objects and performance counters. A performance object is a collection of performance counters for a particular part of the system. Examples of performance objects are Memory, Processor, Physical Disk, Paging file, and IP. A performance counter represents the performance of a particular aspect of a performance object by either a numeric or a % value. By default, System Monitor uses the following objects and counters:

Processor / % Processor Time – When this counter’s value exceeds 85% continuously, it may indicate you need to upgrade the processor.
Memory / Pages/sec - When this counter’s value exceeds 20 continuously, it may indicate you need to add additional RAM.
PhysicalDisk / Avg. Disk Queue Length - When this counter’s value exceeds the number of spindles plus 2 continuously, it may indicate you need to add additional RAM. Disk queue length refers to the number of read and write requests waiting in the disk’s queue.

For a more complete list of performance objects available in Windows XP click here and for acceptable values of additional counters click here. When you add a counter in System Monitor or Performance Logs and Alerts, you can click the Explain button for an explanation.

Instead of displaying the counter values in a real-time graph, Performance Logs and Alerts writes the information to log files on disk. You can configure counter logs, which record data at a specified interval, or trace logs, which record system application events when a specific event occurs such as a disk activity. You will need a parsing tool to interpret trace logs. Trace logs are useful mostly to developers.

Additionally, Performance Logs and Alerts allows you to set Alerts on counters. Setting alerts allows you to start a program, send a message, start a log, or write an entry to the Application log when a counter’s value exceeds or drops below a specified value.


Disk Defragmenter

Windows XP includes performance counters for monitoring performance of physical disks and logical volumes. Depending on the exact results of the System Monitor or Performance Logs and Alerts, all you may need to do to increase disk performance is defragment it. When you save a file to a disk that has been used for some time, it is often not stored as a single contiguous block of data. Instead, it is spread across the disk in small pieces starting with the first available piece of free space – a piece of free space that became available when a file was deleted. This slows down both disk write and read times because the disk heads have to move back and forth excessively.

To reorder the files and folders in a contiguous block of data on disk, you can defragment its volumes by using the graphical utility Disk Defragmenter or the command-line utility Defrag.exe. The latter is suitable for scheduling and scripting. Defragmenting the disk completely requires the volume to have at least 15 percent free space to sort file fragments. You can start the Disk Defragmenter by clicking the Defragment Now button on the Tools tab of a volume’s Properties. Follow the links below for more information about the Disk Defragmenter and defrag.exe.

Disk Defragmenter Limitations in Windows XP

Description of the New Command Line Defrag.exe Included with Windows XP


Scheduled Tasks

You can schedule maintenance tasks by using the Scheduled Tasks feature in Windows XP, which you can access from the control panel. It allows you to run a program, script, batch file, or a document at a predefined date and time. New tasks are added by using the Schedule Task wizard. You can schedule a task to run daily, weekly, monthly, at system startup, at logon, or one time only. After setting a date and time, you will need to provide a username and password for the task. The task will run as if that user started it, hence will have that user’s permissions and rights.

When you add a task by using the wizard, it will be listed in Scheduled Tasks in the control panel. When you open the properties of a task, you can change and configure additional settings such as:
- delete the task if it is not scheduled to run again.
- specify the maximum duration of the task.
- start the task only when the computer is idle for a specified amount of time.
- stop or don’t start the task when the computer is running on batteries.


Visual Effects

On the Visual Effects tab of the Performance Options shown below (click the Settings button in the Performance section of the Advanced tab of the System Properties) you can improve overall performance for working in Windows. By default, Windows automatically chooses the best settings for your computer. Usually these settings are fine, but especially on older computers, it may help to turn of some or all of the visual effects.

Additionally, you can turn of some visual effects on the Appearance tab of the Display Properties, which can also help to improve performance.

 

 
Current related exam objectives for the 70-270 exam:

Monitoring and Optimizing System Performance and Reliability

Monitor, optimize, and troubleshoot performance of the Windows XP Professional desktop.
- Optimize and troubleshoot memory performance.
- Optimize and troubleshoot processor utilization.
- Optimize and troubleshoot disk performance.
- Optimize and troubleshoot application performance.
- Configure, manage, and troubleshoot Scheduled Tasks.

TechExams.Net
Date: Friday, February 04, 2005
Author: Johan Hiemstra
MCSE NT4 MCSA 2000/2003
CCNA CCDA CNA Security+ CWNA