FIX: An endless loop in the CEventDispatcher::RemoveEventBuffer function in the Comsvcs.dll file causes the host COM+ application to stop responding on a computer that is running Windows XP SP2 (905551)


The information in this article applies to:

  • Microsoft COM+ 1.5, when used with:
    • Microsoft Windows XP Professional SP2

SYMPTOMS

Consider the following scenario. On a computer that is running Microsoft Windows XP Service Pack 2 (SP2), an endless loop occurs in the CEventDispatcher::RemoveEventBuffer function in the Comsvcs.dll file. This endless loop causes the host Microsoft COM+ application to stop responding (hang). This host COM+ application uses all or most of the available CPU cycles. In this scenario, you experience slow performance on the computer because of the increased CPU utilization.

Note Typically, the host COM+ application is a Dllhost.exe process.

This problem occurs under heavy load conditions when the following conditions are true:
  • Many events are raised at the same time.
  • The component subscribes to multiple COM+ transient events.

CAUSE

This problem occurs because of a code defect in COM Services (Comsvcs.dll).

RESOLUTION

This problem is fixed in Windows XP Post-Service Pack 2 COM+ 1.0 Hotfix Rollup Package 12. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

910720 Availability of Windows XP COM+ Hotfix Rollup Package 12

Hotfix information

A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that this article describes. Apply it only to systems that are experiencing this specific problem.

To resolve this problem, 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

You must have Microsoft Windows XP Service Pack 1 (SP1) or Microsoft Windows XP Service Pack 2 (SP2) installed to apply this hotfix.

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

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.Windows XP Service Pack 1, x86
File nameFile versionFile sizeDateTimeService pack requirement
Catsrv.dll2001.12.4414.63220,67218-Nov-200515:39SP1
Catsrvut.dll2001.12.4414.63581,63218-Nov-200515:39SP1
Clbcatex.dll2001.12.4414.63110,08018-Nov-200515:39SP1
Clbcatq.dll2001.12.4414.63497,15218-Nov-200514:39SP1
Colbact.dll2001.12.4414.6362,46418-Nov-200515:39SP1
Comadmin.dll2001.12.4414.63187,39218-Nov-200515:39SP1
Comrepl.dll2001.12.4414.6389,60018-Nov-200515:39SP1
Comsvcs.dll2001.12.4414.631,179,13618-Nov-200515:39SP1
Comuid.dll2001.12.4414.63499,20018-Nov-200515:39SP1
Es.dll2001.12.4414.63227,32818-Nov-200515:39SP1
Migregdb.exe2001.12.4414.636,65618-Nov-200500:34SP1
Msdtcprx.dll2001.12.4414.63368,64018-Nov-200515:39SP1
Msdtctm.dll2001.12.4414.63973,82418-Nov-200515:39SP1
Msdtcuiu.dll2001.12.4414.63150,52818-Nov-200515:39SP1
Mtxclu.dll2001.12.4414.6364,51218-Nov-200515:39SP1
Mtxoci.dll2001.12.4414.6383,45618-Nov-200515:39SP1
Ole32.dll5.1.2600.17751,190,40018-Nov-200515:39SP1
Olecli32.dll5.1.2600.177568,60818-Nov-200515:39SP1
Olecnv32.dll5.1.2600.177535,32818-Nov-200515:39SP1
Rpcrt4.dll5.1.2600.1361535,55206-Mar-200402:16SP1
Rpcss.dll5.1.2600.1775276,99218-Nov-200515:40SP1
Srrstr.dll5.1.2600.1775226,81618-Nov-200515:40SP1
Stclient.dll2001.12.4414.6355,29618-Nov-200515:40SP1
Txflog.dll2001.12.4414.6397,28018-Nov-200515:40SP1
Xolehlp.dll2001.12.4414.6311,77618-Nov-200515:40SP1
Windows XP Service Pack 2, x86
File nameFile versionFile sizeDateTimeService pack requirement
Catsrv.dll2001.12.4414.309225,79218-Nov-200515:32SP2
Catsrvut.dll2001.12.4414.309625,15218-Nov-200515:32SP2
Clbcatex.dll2001.12.4414.309110,08018-Nov-200515:32SP2
Clbcatq.dll2001.12.4414.309498,68818-Nov-200515:32SP2
Colbact.dll2001.12.4414.30960,41618-Nov-200515:32SP2
Comadmin.dll2001.12.4414.309195,07218-Nov-200515:32SP2
Comrepl.dll2001.12.4414.30997,79218-Nov-200515:32SP2
Comsvcs.dll2001.12.4414.3091,267,20018-Nov-200515:32SP2
Comuid.dll2001.12.4414.309539,64818-Nov-200515:32SP2
Es.dll2001.12.4414.309243,20018-Nov-200515:32SP2
Migregdb.exe2001.12.4414.3097,68017-Nov-200523:36SP2
Msdtcprx.dll2001.12.4414.309425,98418-Nov-200515:32SP2
Msdtctm.dll2001.12.4414.309955,90418-Nov-200515:32SP2
Msdtcuiu.dll2001.12.4414.309161,28018-Nov-200515:32SP2
Mtxclu.dll2001.12.4414.30966,56018-Nov-200515:32SP2
Mtxoci.dll2001.12.4414.30991,13618-Nov-200515:32SP2
Ole32.dll5.1.2600.27991,285,63218-Nov-200515:32SP2
Olecli32.dll5.1.2600.279974,75218-Nov-200515:32SP2
Olecnv32.dll5.1.2600.279937,37618-Nov-200515:32SP2
Rpcss.dll5.1.2600.2799398,33618-Nov-200515:32SP2
Stclient.dll2001.12.4414.30959,39218-Nov-200515:32SP2
Txflog.dll2001.12.4414.309101,37618-Nov-200515:32SP2
Xolehlp.dll2001.12.4414.30911,77618-Nov-200515:32SP2

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Modification Type:MajorLast Reviewed:12/20/2005
Keywords:kbfix kbQFE kbBug KB905551 kbAudDeveloper kbAudITPRO
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