Windows NT4.0 Print Servers May Experience Paged Pool Leak on FsRt Pooltag (283102)

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256986 Description of the Microsoft Windows Registry

SYMPTOMS

When you are using a Windows NT 4.0-based print server that is running any service pack with spooler print notifications (pop-ups) enabled, the computer may run out of Paged Pool if the users who are submitting the print jobs are not logged on.

When you use the Poolmon tool for a few days, paged pool usage increases due to pooltag elements of type FsRt.

This problem usually occurs on print servers when the print requests are submitted from a Windows NT 4.0 service running under a dedicated service account, and no user is logged on under that account to receive the spooler notifications.

CAUSE

The problem can occur when the spooler generates printing notifications faster than the alerter-messenger remote procedure call (RPC) can dispatch them.

After a variable period of time (one week or more), the print server computer may run out of paged pool and eventually stop responding (hang). This occurs because the spooler notifications use the mailslots mechanism and the messages are stored in paged pool on the server.

If the receiving user is not logged on somewhere on the network, these notification messages cannot be delivered, and eventually exhaust paged pool.

RESOLUTION

To work around this problem, use one of the methods in this section.

Method 1

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

If you do not need the spooler notifications, you can disable them by setting the NetPopUp value in the following registry key:

Key: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Print\Providers

Value: NetPopUp
Type: REG_DWORD
Data value: 0

Method 2

If you enable spooler notifications, verify that the user who should receive the notification is logged on to the network. If the user never logs on interactively (which is usually the case for a service account), printing notifications are accumulated on the server. After a period of time, the paged pool is exhausted and the print server must be restarted. Note that on a computer running Windows NT 4.0, the paged pool size is limited to 192 megabyte (MB).

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

This problem is resolved in Windows 2000 Service Pack 2 (SP2). The messenger is redesigned so that it is multiple threaded in Windows 2000, and SP2 adds an enabler hotfix.