Symptoms
Assume that you have a Visual C++ 2010 application that is developed in Microsoft Visual Studio 2010. The application uses the Open Multiprocessing (OpenMP) API to improve performance on a computer that has multiple processors. You build the application, and you use the /openmp compiler option. When you run the application, the application process might experience high CPU usage.Note This issue does not occur in Microsoft Visual Studio 2008 or in Microsoft Visual Studio 2005.
Cause
This issue occurs because the implementation of the OpenMP runtime (Vcomp100.dll) has a spin-wait loop in which the OpenMP threads look for work for a short time before they are yielded.
Resolution
After you install the hotfix, you must create the OMP_WAIT_POLICY environment variable, and then set the value of the variable to PASSIVE. Notes
-
If you set the value for OMP_WAIT_POLICY to ACTIVE, the OpenMP threads will spin-wait for a short time before blocking when the threads finish executing a workload.
-
If you set the value for OMP_WAIT_POLICY to PASSIVE, the OpenMP threads will immediately be blocked when the threads finish executing a workload.
-
The default value for OMP_WAIT_POLICY is ACTIVE.
Hotfix information
A supported hotfix is now available from Microsoft. However, it is intended to correct only the problem that is described in this article. Apply it only 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 software update that contains this hotfix.To resolve this problem immediately, contact Microsoft Customer Support Services to obtain the hotfix. For a complete list of Microsoft Customer Support Services telephone numbers and information about support costs, visit the following Microsoft website:
http://support.microsoft.com/contactus/?ws=supportNote 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 apply this hotfix, you must have Visual Studio 2010 Service Pack 1 (SP1) installed.
Restart requirement
You must restart the computer after you install the hotfix if the affected files are being used during the installation.
Hotfix replacement information
This hotfix does not replace a previously released hotfix.
File information
The global 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.
For all supported x86-based versions of Microsoft Visual C++ 2010 SP1 Redistributable Package
|
File name |
File version |
File size |
Date |
Time |
Platform |
|---|---|---|---|---|---|
|
Atl100.dll |
10.0.40219.436 |
138,800 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfc100.dll |
10.0.40219.436 |
4,400,688 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfc100chs.dll |
10.0.40219.436 |
36,912 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfc100cht.dll |
10.0.40219.436 |
36,912 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfc100deu.dll |
10.0.40219.436 |
65,096 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfc100enu.dll |
10.0.40219.436 |
55,880 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfc100esn.dll |
10.0.40219.436 |
64,560 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfc100fra.dll |
10.0.40219.436 |
65,072 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfc100ita.dll |
10.0.40219.436 |
63,048 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfc100jpn.dll |
10.0.40219.436 |
44,592 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfc100kor.dll |
10.0.40219.436 |
44,104 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfc100rus.dll |
10.0.40219.436 |
61,512 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfc100u.dll |
10.0.40219.436 |
4,425,776 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfcm100.dll |
10.0.40219.436 |
82,496 |
14-Dec-2012 |
06:35 |
x86 |
|
Mfcm100u.dll |
10.0.40219.436 |
82,496 |
14-Dec-2012 |
06:35 |
x86 |
|
Msvcp100.dll |
10.0.40219.436 |
421,936 |
14-Dec-2012 |
06:35 |
x86 |
|
Msvcr100_clr0400.dll |
10.0.40219.436 |
774,192 |
14-Dec-2012 |
06:35 |
x86 |
|
Vcomp100.dll |
10.0.40219.436 |
52,288 |
14-Dec-2012 |
06:35 |
x86 |
For all supported x64-based versions of Microsoft Visual C++ 2010 SP1 Redistributable Package
|
File name |
File version |
File size |
Date |
Time |
Platform |
|---|---|---|---|---|---|
|
Atl100.dll |
10.0.40219.436 |
159,280 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfc100.dll |
10.0.40219.436 |
5,579,824 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfc100chs.dll |
10.0.40219.436 |
36,912 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfc100cht.dll |
10.0.40219.436 |
36,936 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfc100deu.dll |
10.0.40219.436 |
65,072 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfc100enu.dll |
10.0.40219.436 |
55,880 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfc100esn.dll |
10.0.40219.436 |
64,560 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfc100fra.dll |
10.0.40219.436 |
65,096 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfc100ita.dll |
10.0.40219.436 |
63,024 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfc100jpn.dll |
10.0.40219.436 |
44,592 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfc100kor.dll |
10.0.40219.436 |
44,080 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfc100rus.dll |
10.0.40219.436 |
61,488 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfc100u.dll |
10.0.40219.436 |
5,605,952 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfcm100.dll |
10.0.40219.436 |
93,744 |
14-Dec-2012 |
05:46 |
x64 |
|
Mfcm100u.dll |
10.0.40219.436 |
93,744 |
14-Dec-2012 |
05:46 |
x64 |
|
Msvcp100.dll |
10.0.40219.436 |
608,816 |
14-Dec-2012 |
05:46 |
x64 |
|
Msvcr100_clr0400.dll |
10.0.40219.436 |
830,016 |
14-Dec-2012 |
05:46 |
x64 |
|
Vcomp100.dll |
10.0.40219.436 |
58,944 |
14-Dec-2012 |
05:46 |
x64 |
For all supported IA-64-based versions of Microsoft Visual C++ 2010 SP1 Redistributable Package
|
File name |
File version |
File size |
Date |
Time |
Platform |
|---|---|---|---|---|---|
|
Atl100.dll |
10.0.40219.436 |
386,096 |
14-Dec-2012 |
06:07 |
IA-64 |
|
Msvcp100.dll |
10.0.40219.436 |
967,232 |
14-Dec-2012 |
06:07 |
IA-64 |
|
Msvcr100_clr0400.dll |
10.0.40219.436 |
1,500,224 |
14-Dec-2012 |
06:07 |
IA-64 |
|
Vcomp100.dll |
10.0.40219.436 |
144,448 |
14-Dec-2012 |
06:07 |
IA-64 |
More Information
For more information about the OpenMP API in Visual Studio 2010, go to the following MSDN website:
General information about the OpenMP APIFor more information about OpenMP in Visual C++, go to the following MSDN website:
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
