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Brian Posey, one of the best (in my opinion) contributing writers to TechRepublic, has a great article on his Web site about memory and virtural memory. He uses a windows 2000 Server as an example, but the same will apply to W2K Professional as well.

An excerpt from the article:

The reason that memory plays such a huge role in a Windows server?s performance is because Windows doesn?t rely purely on physical memory. It also relies on virtual memory. Virtual memory is a file on the hard disk that?s designed to be addressable in the same way that physical memory is. The basic idea is that when the physical memory gets to be too full, Windows moves some of the physical memory?s contents to virtual memory, thus freeing space within the physical memory. When the machine needs to work with data that was moved to virtual memory, something else is transferred from physical memory to virtual memory. This leaves some empty space in the physical memory. The machine then moves the necessary blocks from virtual memory into the free space in the physical memory so that the code can be manipulated. This process is known as swapping.

There are several reasons why the use of virtual memory has such a negative impact on over all system performance. First, the swapping process consumes system resources. Keep in mind that the entire swapping process is software driven. Therefore, CPU cycles are used while running the swapping algorithms. Likewise, hard disk time is also used in the process. Believe it or not, even memory space is used in swapping. Your system needs a location where it cam temporarily store blocks that are being swapped. This temporary location exists within the machine?s physical memory. The point is that your system is using a considerable amount of resources just to run a process that will make it run more slowly.

Another reason why swapping is so slow is because of disk transfer rates. Memory access speeds are measured in nanoseconds, or billionths of a second. Disk transfer rates are measured in milliseconds, or millionth?s of a second. As you can see, reading from and writing to disk is an inherently slow process when compared to performing the same operation in memory. That is why RAM drives were so popular in the early 1990?s.

>>>>>End of excerpt

A link to the article:

http://www.brienposey.com/kb/memory_management.asp

Just as a side thought, make sure you have a hard drive with enough free space to facilitate swapping. Also, 128 MB of RAM is, in my opinion, too little. 256 MB is my personal minimum for W2K. I prefer 512 MB, and it really runs well with 1 GB.

There is no specific "formula" for the optimum amount of Virtual Memory or RAM.

The amount of RAM and virtual memory needed is dependent upon how the PC is used.

The old school rule of 2 times installed RAM is VERY out of date. It goes back to Windows 3.11 which did not make good use of the page file.

For Windows 2K, the maximum virtual memory is 4GB.

What I do, is install as much RAM as the motherboard will hold (or the user can afford).
I then use a 1GB or so logical drive on an extended partition and dedicate it for Virtual Memory.

A very good article on virtual memory is posted at www.aumha.org

If you want to take the time to "optimize" virtual memory settings, what you need to do is:

Make the page file as large as possible.

Log page file usage.

Set the page file to at least 10% more than the largest amount used.

Chas

make 20 to 25 0/0 of each machine (to a max of 500 mg )and on your server make it 10 0/0 ( to a max of 600 mg )this lets the read ahead of the server just keep ahead of the clients. Now go to the start menue of all your computers and enter msconfig. go to startup and shut off all programs that are running extra.(such as games and extra programms that are not used regularly.
save and then rebot each machine. When each machine starts up it will ask if you want to redo or change the settring you have set.click do not show,then close program. this is in layman terms ,but i think when you go into these programms ,you'll now what i mean.
Let me know of your progress.
PS
...the less games you have running on the server the faster the slaves will go and vice versa.

The Woodbutcher

...Bill