Using Swap Files on Networks in Windows

• Microsoft Windows operating system versions 3.0, 3.0a, 3.1, 3.11

SUMMARY

This article discusses the use of Microsoft Windows and swap files on network drives. The following topics are included:

• Can swap files be created on a network drive?
• Why does Windows take so long to start in 386 enhanced mode?

MORE INFORMATION

Can Swap Files be Created on a Network Drive?

Network drives do not support the INT13h calls needed to set up a permanent swap file. A temporary swap file can be set up on a network drive where you have full privileges (rights) including creation rights if you are on a Novell network.

Approximately 2 MB of free hard disk space is required. You cannot have multiple workstations using the same swap file; therefore, if you set up a swap file on a network drive, it should be in the user's directory where no one else but the user can access it.

If possible, set up the swap file on your local workstation's hard drive. Benefits of this configuration include the following:

• Performance for the workstation
• Performance for the network (cuts down on network traffic)
• Provides the ability to set up a permanent swap file

Why Does Windows Take So Long to Start in 386 Enhanced Mode?

Temporary swap files on a network can make the loading of Windows slow. This can also affect the speed at which Windows runs in 386 enhanced mode while Windows tries to swap files. This affects both Windows and non- Windows-based applications.

When you load Windows, the temporary swap file is initialized in the startup location of WIN.COM. Because a network drive normally has a large amount of free disk space, this swap file can become large. 386 enhanced mode initializes the temporary swap file to about half of the available contiguous free disk space.

Initializing this large swap file can take a long time and can cause Windows to take more than one minute to load.

There are three ways to avoid this problem:

1. The first step is to change the location of the temporary swap file. Change the PagingDrive= in the [386Enh] section of the SYSTEM.INI file to a local drive. For example:

         PagingDrive=C:
   

   NOTE: For a diskless workstation, this won't be an option. A network drive must be used.

2. You can also limit the size of the swap file by using the MaxPagingFileSize= statement in the [386Enh] section of the SYSTEM.INI. For example:

         MaxPagingFileSize=[Amount in Kilobytes]
   

   NOTE: Using a smaller size swap file speeds up the initialization of the swap file and makes access to it faster as well. This also limits the amount of virtual memory available.

3. Using Notepad, you can disable paging completely by editing the Paging= line in the [386Enh] section of the SYSTEM.INI file.

         Paging=NO
   

   NOTE: Microsoft does not recommend setting Paging=NO as a Long-term solution because this may adversely affect the performance of Windows.