You may experience slow performance when you view a Web page that uses JScript in Internet Explorer 6 (919237)


The information in this article applies to:

  • Microsoft Windows Server 2003, Standard Edition
  • Microsoft Windows Server 2003, Enterprise Edition
  • Microsoft Windows Server 2003, Datacenter Edition
  • Microsoft Windows Server 2003, Web Edition
  • Microsoft Windows Server 2003, Standard x64 Edition
  • Microsoft Windows Server 2003, Enterprise x64 Edition
  • Microsoft Windows Server 2003, Datacenter x64 Edition
  • Microsoft Windows Server 2003, Enterprise Edition for Itanium-based Systems
  • Microsoft Windows Server 2003, Datacenter Edition for Itanium-based Systems
  • Microsoft Windows Server 2003 R2 Standard Edition (32-bit x86)
  • Microsoft Windows Server 2003 R2 Enterprise Edition (32-Bit x86)
  • Microsoft Windows Server 2003 R2 Datacenter Edition (32-Bit x86)
  • Microsoft Windows Server 2003 R2 Standard x64 Edition
  • Microsoft Windows Server 2003 R2 Enterprise x64 Edition
  • Microsoft Windows Server 2003 R2 Datacenter x64 Edition
  • Microsoft Windows XP Home Edition
  • Microsoft Windows XP Professional
  • Microsoft Windows XP Professional 64-Bit Edition (Itanium)
Important This article contains information about how to modify the registry. Make sure to back up the registry before you modify it. Make sure that you know how to restore the registry if a problem occurs. For more information about how to back up, restore, and modify the registry, click the following article number to view the article in the Microsoft Knowledge Base:

256986 Description of the Microsoft Windows registry

SYMPTOMS

When you use Microsoft Internet Explorer 6 to view a Web page that uses Microsoft JScript, you may experience slow performance.

CAUSE

This problem may occur when a script creates many variables at the same time. The problem may also occur when a script contains many unique values that are parsed at the same time. The problem occurs because of the way the JScript engine performs garbage collection.

The garbage collection algorithm monitors the following values:
  • The number of variable allocations in the script
  • The number of literal values that are used in the script
  • The total size of the string values that are allocated in the script
When thresholds for these values are exceeded, garbage collection occurs. The garbage collection process interrupts scripts that are running. Therefore, the scripts are suspended until garbage collection is completed.

RESOLUTION

Microsoft Windows XP

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 XP 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 You must have Microsoft Windows XP Service Pack 2 (SP2) installed to apply this hotfix. If you need to install this update on Windows XP 64-bit Edition, install the Microsoft Windows 2003 x64 update on the x64 version on Windows XP.Restart requirementYou must restart the computer after you apply this hotfix.Registry informationWarning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

This hotfix provides three registry configuration options that you can use to customize the frequency of garbage collection in JScript. These options can provide a more optimal user experience when you run scripts that use many variables, use many values, or allocate lots of strings.

After you apply this hotfix, follow these steps to configure these registry configuration options:
  1. Click Start, click Run, type regedit, and then click OK.
  2. Locate and then click the following registry subkey:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft

  3. On the Edit menu, point to New, and then click Key.
  4. Type Windows Script, and then press ENTER.
  5. Right-click Windows Script, click New, and then click Key.
  6. Type Features, and then press ENTER.
  7. Right-click Features, click New, and then click Key.
  8. Type Iexplore, and then press ENTER.

    Note This registry entry sets JScript garbage collector options for Internet Explorer. You can add more registry entries to set JScript garbage collector options for other programs. In each entry, use the executable file name without the file name extension.
  9. Right-click Iexplore, click New, and then click DWORD Value.
  10. Type GcVarTrigger, and then press ENTER.
  11. Right-click GcVarTrigger, and then click Modify.
  12. In the Value data box, type a value to set the number of variables that can be allocated in JScript before garbage collection occurs, and then click OK.

    Note The default value is 0x00000100. We recommend an initial value of 0x00000500.
  13. Right-click Iexplore, click New, and then click DWORD Value.
  14. Type GcValTrigger, and then press ENTER.
  15. Right-click GcValTrigger, and then click Modify.
  16. In the Value data box, type a value to set the number of literal values that can be allocated in JScript before garbage collection occurs, and then click OK.

    Note The default value is 0x00001000. We recommend an initial value of 0x00005000.
  17. Right-click Iexplore, click New, and then click DWORD Value.
  18. Type GccbSysTrigger, and then press ENTER.
  19. Right-click GccbSysTrigger, and then click Modify.
  20. In the Value data box, type a value to set the number of string value space in bytes that can be allocated in JScript before garbage collection occurs. and then click OK.

    Note The default value is 0x00010000. We recommend an initial value of 0x00020000.
  21. Exit Registry Editor, and then restart the computer.
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 item in Control Panel.

Microsoft Windows XP, 32-bit versions
File nameFile versionFile sizeDateTimePlatform
Jscript.dll5.6.0.8832450,56019-Jul-200610:43x86
Microsoft Windows XP Professional x64 Edition
File nameFile versionFile sizeDateTimePlatform
Jscript.dll5.6.0.8831998,91219-Jul-200623:58x64

Windows Server 2003

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 Server 2003 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.PrerequisitesYou must have Windows Server 2003 Service Pack 1 (SP1) installed to apply this hotfix.Restart requirementYou must restart the computer after you apply this hotfix.Registry informationWarning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

This hotfix provides three registry configuration options that you can use to customize the frequency of garbage collection in JScript. These options can provide a more optimal user experience when you run scripts that use many variables, use many values, or allocate lots of strings.

After you apply this hotfix, follow these steps to configure these registry configuration options:
  1. Click Start, click Run, type regedit, and then click OK.
  2. Locate and then click the following registry subkey:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft

  3. On the Edit menu, point to New, and then click Key.
  4. Type Windows Script, and then press ENTER.
  5. Right-click Windows Script, click New, and then click Key.
  6. Type Features, and then press ENTER.
  7. Right-click Features, click New, and then click Key.
  8. Type Iexplore, and then press ENTER.

    Note This registry entry sets JScript garbage collector options for Internet Explorer. You can add more registry entries to set JScript garbage collector options for other programs. In each entry, use the executable file name without the file name extension.
  9. Right-click Iexplore, click New, and then click DWORD Value.
  10. Type GcVarTrigger, and then press ENTER.
  11. Right-click GcVarTrigger, and then click Modify.
  12. In the Value data box, type a value to set the number of variables that can be allocated in JScript before garbage collection occurs, and then click OK.

    Note The default value is 0x00000100. We recommend an initial value of 0x00000500.
  13. Right-click Iexplore, click New, and then click DWORD Value.
  14. Type GcValTrigger, and then press ENTER.
  15. Right-click GcValTrigger, and then click Modify.
  16. In the Value data box, type a value to set the number of literal values that can be allocated in JScript before garbage collection occurs, and then click OK.

    Note The default value is 0x00001000. We recommend an initial value of 0x00005000.
  17. Right-click Iexplore, click New, and then click DWORD Value.
  18. Type GccbSysTrigger, and then press ENTER.
  19. Right-click GccbSysTrigger, and then click Modify.
  20. In the Value data box, type a value to set the number of string value space in bytes that can be allocated in JScript before garbage collection occurs. and then click OK.

    Note The default value is 0x00010000. We recommend an initial value of 0x00020000.
  21. Exit Registry Editor, and then restart the computer.
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 item in Control Panel.

Microsoft Windows Server 2003 with Service Pack 1
File nameFile versionFile sizeDateTimePlatform
Jscript.dll5.6.0.8831458,75220-Jul-200602:40x86
Microsoft Windows Server 2003, x64-based versions
File nameFile versionFile sizeDateTimePlatform
Jscript.dll5.6.0.8831998,91219-Jul-200623:58x64

STATUS

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

MORE INFORMATION

For more information about JScript, visit the following Microsoft Developer Network (MSDN) Web site:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/script56/html/1e9b3876-3d38-4fd8-8596-1bbfe2330aa9.asp

For more information about the terms that are used in this article, 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

Technical support for x64-based versions of Microsoft Windows

If your hardware came with a Microsoft Windows x64 edition already installed, your hardware manufacturer provides technical support and assistance for the Windows x64 edition. In this case, your hardware manufacturer provides support because a Windows x64 edition was included with your hardware. Your hardware manufacturer might have customized the Windows x64 edition installation by using unique components. Unique components might include specific device drivers or might include optional settings to maximize the performance of the hardware. Microsoft will provide reasonable-effort assistance if you need technical help with a Windows x64 edition. However, you might have to contact your manufacturer directly. Your manufacturer is best qualified to support the software that your manufacturer installed on the hardware. If you purchased a Windows x64 edition such as a Microsoft Windows Server 2003 x64 edition separately, contact Microsoft for technical support.

For product information about Microsoft Windows XP Professional x64 Edition, visit the following Microsoft Web site:

http://www.microsoft.com/windowsxp/64bit/default.mspx

For product information about x64-based versions of Microsoft Windows Server 2003, visit the following Microsoft Web site:

http://www.microsoft.com/windowsserver2003/64bit/x64/default.mspx

Modification Type:MinorLast Reviewed:9/1/2006
Keywords:kbfix kbBug kbWebBrowser kbQFE kbhotfixserver kbpubtypekc KB919237 kbAudDeveloper
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