FIX: System Performance Is Affected When You Initiate Network Activity (831466)


The information in this article applies to:

  • Microsoft Windows CE .NET 4.1

SYMPTOMS

After a period of network inactivity, if you perform an operation that initiates network activity, performance of the Microsoft Windows CE operating system is affected. You may experience one or both of the following symptoms:
  • The user interface responds more slowly.
  • Integrated and attached devices do not operate correctly.
Diagnostics on the performance of the operating system show that a thread in CxPort is using a large percentage of CPU cycles.

CAUSE

This problem occurs because a counter variable in a timer is incorrect. Specifically, while network communication is inactive, a timer that controls network tasks is turned off. When network communication starts again, the timer is turned on. However, a counter variable that is used to process the task is not correctly reset. As a result, the counter variable incorrectly includes the count of milliseconds that the timer was turned off.

The thread that performs the tasks is in the CxPort module and typically runs at priority level 132 (this level is higher than most other system thread levels). Because this thread does not yield, the thread continues to execute a long loop. This behavior results in high CPU usage until the loop terminates.

RESOLUTION

Hotfix Information

A supported software update is now available from Microsoft as Windows CE 4.1 Core OS QFE 831466. To resolve this problem immediately, click the following article number for information about obtaining Windows CE Platform Builder and core operating system software updates:

837392 How to locate core operating system fixes for Microsoft Windows CE Platform Builder products

Prerequisites

This fix is supported only when all previously issued fixes for this product have also been installed.

Restart Requirement

After you apply this update, you must perform a clean operation and then rebuild the platform.

Hotfix Replacement Information

This hotfix does not replace any other hotfixes.

File Information

The English version of this package has the file attributes (or later) that are listed in the following table. 
   Date         Time   Version            Size    File name
   -----------------------------------------------------------------------------------------
   14-Nov-2003  19:35  4.10            1,223,224  Wincepb41-031114-kb831466-armv4.exe  
   14-Nov-2003  19:37  4.10            1,223,224  Wincepb41-031114-kb831466-armv4i.exe
   14-Nov-2003  19:36  4.10            1,227,320  Wincepb41-031114-kb831466-armv4t.exe
   14-Nov-2003  19:36  4.10            1,243,704  Wincepb41-031114-kb831466-mips16.exe  
   14-Nov-2003  19:36  4.10            1,260,088  Wincepb41-031114-kb831466-mipsii.exe
   14-Nov-2003  19:37  4.10            1,260,088  Wincepb41-031114-kb831466-mipsii_fp.exe
   14-Nov-2003  19:37  4.10            1,268,280  Wincepb41-031114-kb831466-mipsiv.exe
   14-Nov-2003  19:37  4.10            1,268,280  Wincepb41-031114-kb831466-mipsiv_fp.exe
   14-Nov-2003  19:35  4.10            1,186,360  Wincepb41-031114-kb831466-sh3.exe
   14-Nov-2003  19:35  4.10            1,186,360  Wincepb41-031114-kb831466-sh4.exe
   14-Nov-2003  19:35  4.10            1,133,112  Wincepb41-031114-kb831466-x86.exe
The English version of this hotfix has the file attributes (or later) 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         Size    File name
   --------------------------------------------------------------

   Path: Public\Common\Oak\Lib\Armv4\Debug
   29-Oct-2003  23:20                  1,078,128  Tcp.lib
   29-Oct-2003  23:20                    143,360  Tcp.pdb

   Path: Public\Common\Oak\Lib\Armv4\Retail
   29-Oct-2003  23:20                    790,270  Tcp.lib
   29-Oct-2003  23:20                    126,976  Tcp.pdb

   Path: Public\Common\Oak\Lib\Armv4i\Debug
   29-Oct-2003  23:20                  1,079,434  Tcp.lib
   29-Oct-2003  23:20                    143,360  Tcp.pdb

   Path: Public\Common\Oak\Lib\Armv4i\Retail
   29-Oct-2003  23:19                    791,988  Tcp.lib
   29-Oct-2003  23:19                    126,976  Tcp.pdb

   Path: Public\Common\Oak\Lib\Armv4t\Debug
   29-Oct-2003  23:19                    996,848  Tcp.lib
   29-Oct-2003  23:19                    143,360  Tcp.pdb

   Path: Public\Common\Oak\Lib\Armv4t\Retail
   29-Oct-2003  23:19                    790,424  Tcp.lib
   29-Oct-2003  23:19                    126,976  Tcp.pdb

   Path: Public\Common\Oak\Lib\Mips16\Debug
   29-Oct-2003  23:22                  1,111,332  Tcp.lib
   29-Oct-2003  23:22                    143,360  Tcp.pdb

   Path: Public\Common\Oak\Lib\Mips16\Retail
   29-Oct-2003  23:21                    740,274  Tcp.lib
   29-Oct-2003  23:21                    135,168  Tcp.pdb

   Path: Public\Common\Oak\Lib\Mipsii\Debug
   29-Oct-2003  23:21                  1,111,332  Tcp.lib
   29-Oct-2003  23:21                    143,360  Tcp.pdb

   Path: Public\Common\Oak\Lib\Mipsii\Retail
   29-Oct-2003  23:21                    796,970  Tcp.lib
   29-Oct-2003  23:21                    135,168  Tcp.pdb

   Path: Public\Common\Oak\Lib\Mipsii_fp\Debug
   29-Oct-2003  23:22                  1,111,512  Tcp.lib
   29-Oct-2003  23:22                    143,360  Tcp.pdb

   Path: Public\Common\Oak\Lib\Mipsii_fp\Retail
   29-Oct-2003  23:22                    797,146  Tcp.lib
   29-Oct-2003  23:22                    135,168  Tcp.pdb

   Path: Public\Common\Oak\Lib\Mipsiv\Debug
   29-Oct-2003  23:25                  1,123,852  Tcp.lib
   29-Oct-2003  23:25                    143,360  Tcp.pdb

   Path: Public\Common\Oak\Lib\Mipsiv\Retail
   29-Oct-2003  23:24                    802,294  Tcp.lib
   29-Oct-2003  23:24                    135,168  Tcp.pdb

   Path: Public\Common\Oak\Lib\Mipsiv_fp\Debug
   29-Oct-2003  23:23                  1,124,032  Tcp.lib
   29-Oct-2003  23:23                    143,360  Tcp.pdb

   Path: Public\Common\Oak\Lib\Mipsiv_fp\Retail
   29-Oct-2003  23:23                    802,476  Tcp.lib
   29-Oct-2003  23:23                    135,168  Tcp.pdb

   Path: Public\Common\Oak\Lib\Sh3\Debug
   29-Oct-2003  23:23                    928,508  Tcp.lib
   29-Oct-2003  23:23                    143,360  Tcp.pdb

   Path: Public\Common\Oak\Lib\Sh3\Retail
   29-Oct-2003  23:22                    721,348  Tcp.lib
   29-Oct-2003  23:22                    135,168  Tcp.pdb

   Path: Public\Common\Oak\Lib\Sh4\Debug
   29-Oct-2003  23:24                    928,066  Tcp.lib
   29-Oct-2003  23:24                    143,360  Tcp.pdb

   Path: Public\Common\Oak\Lib\Sh4\Retail
   29-Oct-2003  23:24                    718,768  Tcp.lib
   29-Oct-2003  23:24                    126,976  Tcp.pdb

   Path: Public\Common\Oak\Lib\X86\Debug
   29-Oct-2003  23:18                    922,010  Tcp.lib
   29-Oct-2003  23:18                    135,168  Tcp.pdb

   Path: Public\Common\Oak\Lib\X86\Retail
   29-Oct-2003  23:18                    683,530  Tcp.lib
   29-Oct-2003  23:18                    126,976  Tcp.pdb

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section of this article.

MORE INFORMATION

For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

824684 Description of the Standard Terminology That Is Used to Describe Microsoft Software Updates

For additional information about a similar issue that occurs with Windows CE .NET version 4.2, click the following article number to view the article in the Microsoft Knowledge Base:

829607 FIX: The CxPort Thread May Use Extreme CPU Cycles and May Affect Other Programs

Modification Type:MinorLast Reviewed:5/27/2005
Keywords:kbBug kbfix kbQFE KB831466 kbAudDeveloper kbAudOEM
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