You can find out if memory or CPU upgrade is needed by configuring Performance Monitor to track memory and CPU usage.

You can then interpret the results and decide whether upgrade will improve the performance.

Use this guide before adding more RAM or upgrading CPU to a system with slow performance.

Creating a performance monitor

Lets begin with creating customized Performance Monitor which will provide focus on memory and CPU usage. Then, you can quickly and easily use it at any time for other systems.

1.         Run mmc from the Run dialog box.

2.         Save the Console and name it as Performance Trace for PC.

3.         Click on Add/Remove Snap-in

4.         Click on the Add button.

5.         Add the ActiveX Control.

6.         Click Next and select System Monitor Control.

7.         Click Next and type Performance Trace for PC.

Once you have created your Performance Trace for PC console, you need to add counters.

 

On the Performance Monitor toolbar click on the Add button and add the following counters:

•           Memory – Available Mbytes

•          Memory – Pages/sec

•           Paging File – % Usage

•           PhysicalDisk – % Disk Time

•           Server – Pool Nonpaged Failures

•           Server – Pool paged Failures

•           Processor – % Processor Time

Download the .htm version of  Performance Trace for PC. If the fie does not open after download, right click it, select properties and press unblock.

By default, the sample interval is set to 1 second, as such, you will want to extend the value. To do so, On the Performance Monitor toolbar click on the Properties button, and change on the General tab the interval to 15 in order to extend the duration of the data collection to 25 Minutes or 36 for 1 hour, for other duration divide the time you want (in minutes) to 1.666667 (ex: 60min/1.666667=36).

Monitoring memory ans CPU usage

You are now ready to start your monitoring operation. Click the Clear Display button on the toolbar and minimize the window.

Now, perform all types of tasks that you do on a normal day in order to get an accurate picture of memory and CPU usage. When the period time is finished, maximized the Performance monitor window and click on the Freeze Display button on the toolbar.

Conclusions

The threshold of each counters are described below:

Performance Object	Counter	Preferred or Ideal Value	Description
Memory	Available MBs	More than 4MB for average and maximum value.	The amount of physical memory, in MBs, immediately available for allocation to any processes.
Memory	Pages/sec	Less than 20 for average and maximum value.	Shows the number of pages being read from or written to virtual memory.
Paging file	Percent usage	Less than 75 percent	Review this value in conjunction with memory available megabytes to understand paging activity.
Physical Disk	Percent Disk time_total	Less than 50 percent	If this value is very high, the system is spending a lot of time paging
Server	Pool Nonpaged FailuresPool paged Failures	The value of both counters should be 0	The both counters indicate the number of times that the operating system couldn’t find any available memory in either of the pools of physical memory.
Processor	% Processor Time	Less than 80 percent for average value	The total percentage of processor usage.

In optimal situation all the above counters values need to be below the threshold counter, however the goal is to take all the counters as a whole, and not to jump to conclusions from one counter result, so if most of the counters values equal or above the Ideal value this is a good indication that the system needs more memory.

If the total percentage of processor usage is more than 80 percent for the average value its indication that the system need CPU upgrade.