TCP/IP port printing may be slow in Windows 2000 (816627)

CAUSE

The buffer size for reading spooled files is only 4 KB for the Windows print processor and for TCP/IP Port Monitor. This causes 2 packets with 1,460 KB of data, followed by another packet with 1,176 KB of data with the TCP Push bit flag enabled. If the print device ignores the TCP Push bit flag, a "Delayed Ack" is typically generated while waiting for another packet. The "Delayed Ack" value frequently uses a value of 0.2 seconds. A "Delayed Ack" should not occur if the packet TCP Push bit flag is enabled.

RESOLUTION

Hotfix information

A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Only apply it to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next Windows 2000 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/contactus/?ws=support

Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

Prerequisites

To install this hotfix, you must have Microsoft Windows 2000 Service Pack 3 (SP3) or later installed on the computer.

Restart requirement

You must restart the computer after you apply this hotfix.

File information

The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.

   Date        Time  Version       Size    File name
   ----------------------------------------------------
   11-Jun-2003 19:03 5.0.2195.6749 252,176 Localspl.dll
   11-Jun-2003 19:03 5.0.2195.6741  80,656 Spoolss.dll
   11-Jun-2003 19:03 5.0.2195.6737  42,256 Tcpmon.dll
   11-Jun-2003 19:03 5.0.2195.6681  97,040 Win32spl.dll

MORE INFORMATION

The Windows print processor and the LPR Read buffers have been increased to 64 kilobytes (KB) to improve performance. This increase leads to fewer delays. If the print device correctly processes the Push bit on the last packet of the buffer, the delay does not occur.

For more information about TCP/IP behavior, search the Microsoft Web site for "Nagle algorithm" or for "RFC1122."

For more information about how to obtain a hotfix for Windows 2000 Datacenter Server, click the following article number to view the article in the Microsoft Knowledge Base:

265173 The Datacenter Program and Windows 2000 Datacenter Server product