Notice: This website is an unofficial Microsoft Knowledge Base (hereinafter KB) archive and is intended to provide a reliable access to deleted content from Microsoft KB. All KB articles are owned by Microsoft Corporation. Read full disclaimer for more details.

Network communication is very slow in a virtual machine that has the LSO feature of Hyper-V Network Virtualization enabled


View products that this article applies to.

Symptoms

When you have a virtual machine that has the Large Send Offload (LSO) feature of Hyper-V Network Virtualization enabled, network communication is very slow. 

↑ Back to the top


Cause

This problem occurs because of an issue in the LSO feature of Hyper-V Network Virtualization. The Push bit is not being propagated correctly, and this causes the push timer to be invoked.

↑ Back to the top


Resolution

Hotfix information

A supported hotfix is available from Microsoft Support. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing the problem described in this article. This hotfix might 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.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, go to the following Microsoft website: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.

Prerequisites

To apply this hotfix, you must be running Windows 8.1 or Windows Server 2012 R2.

Additionally, you must first install update 2919355 on Windows 8.1 or Windows Server 2012 R2.

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any previously released hotfix.

↑ Back to the top


File information
The English (United States) version of this hotfix installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.

Windows 8.1 and Windows Server 2012 R2 file information and notes

Important Windows 8.1 and Windows Server 2012 R2 hotfixes are included in the same packages. However, only "Windows 8.1" is listed on the Hotfix Request page. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows 8.1" on the page. Always refer to the "Applies To" section in articles to determine the actual operating system that each hotfix applies to.
  • The files that apply to a specific product, milestone (RTM,SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table.

    VersionProductMilestoneService branch
    6.3.960 0.16 xxxWindows 8.1 and Windows Server 2012 R2RTMGDR
    6.3.960 0.17 xxxWindows 8.1 and Windows Server 2012 R2RTMDR
  • The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information for Windows 8.1 and Windows Server 2012 R2" section. MUM and MANIFEST files, and the associated security catalog (.cat) files, are extremely important to maintain the state of the updated components. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.
For all supported x64-based versions of Windows 8.1 and Windows Server 2012 R2
File nameFile versionFile sizeDateTimePlatform
Wnv.sys6.3.9600.17084706,04828-Mar-201406:28x64
Vmsntfy.dll6.3.9600.1638488,57622-Aug-201310:49x64

Additional file information

Additional file information for Windows 8.1 and Windows Server 2012 R2

Additional files for all supported x64-based versions of Windows 8.1 and Windows Server 2012 R2
File nameAmd64_1066018ab12bb8e1d11653f3cd1d98dc_31bf3856ad364e35_6.3.9600.17084_none_463fb732d6f2dc74.manifest
File versionNot applicable
File size708
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File nameAmd64_2e910e18c9787499ca85e346060f53f8_31bf3856ad364e35_6.3.9600.17084_none_0016ea03766d9463.manifest
File versionNot applicable
File size701
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File nameAmd64_692b627d3aa6079eb47d150e4d59248e_31bf3856ad364e35_6.3.9600.17084_none_ffc48e9508e9511e.manifest
File versionNot applicable
File size725
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File nameAmd64_dde236bfd7d00860b87bac9599cfe49e_31bf3856ad364e35_6.3.9600.17084_none_c7d38a52dd5a3ab5.manifest
File versionNot applicable
File size695
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File nameAmd64_microsoft-hyper-v-d..ch-coresystem-state_31bf3856ad364e35_6.3.9600.17084_none_e85405a2439043e0.manifest
File versionNot applicable
File size10,075
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File nameAmd64_microsoft-hyper-v-drivers-vmswitch_31bf3856ad364e35_6.3.9600.17084_none_59c97d1454141111.manifest
File versionNot applicable
File size7,637
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File nameAmd64_microsoft-windows-ndis-lbfo_31bf3856ad364e35_6.3.9600.17084_none_02224435eac7fe98.manifest
File versionNot applicable
File size21,660
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File nameAmd64_microsoft-windows-wnv_31bf3856ad364e35_6.3.9600.17084_none_a0645a2f2abb5681.manifest
File versionNot applicable
File size54,090
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File nameAmd64_wvms_pp.inf_31bf3856ad364e35_6.3.9600.17084_none_53a3d6eec5598a05.manifest
File versionNot applicable
File size3,379
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File nameAmd64_wvms_pp_coresys.inf_31bf3856ad364e35_6.3.9600.17084_none_6221ea3160489a34.manifest
File versionNot applicable
File size3,411
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File namePackage_1_for_kb2956241~31bf3856ad364e35~amd64~~6.3.1.0.mum
File versionNot applicable
File size2,304
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File namePackage_2_for_kb2956241~31bf3856ad364e35~amd64~~6.3.1.0.mum
File versionNot applicable
File size1,908
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File namePackage_3_for_kb2956241~31bf3856ad364e35~amd64~~6.3.1.0.mum
File versionNot applicable
File size2,004
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File namePackage_4_for_kb2956241~31bf3856ad364e35~amd64~~6.3.1.0.mum
File versionNot applicable
File size1,873
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File namePackage_5_for_kb2956241~31bf3856ad364e35~amd64~~6.3.1.0.mum
File versionNot applicable
File size1,847
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File namePackage_6_for_kb2956241~31bf3856ad364e35~amd64~~6.3.1.0.mum
File versionNot applicable
File size2,074
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File namePackage_for_kb2956241_rtm_gm~31bf3856ad364e35~amd64~~6.3.1.0.mum
File versionNot applicable
File size2,806
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable
File namePackage_for_kb2956241_rtm~31bf3856ad364e35~amd64~~6.3.1.0.mum
File versionNot applicable
File size3,471
Date (UTC)30-Mar-2014
Time (UTC)01:33
PlatformNot applicable

↑ Back to the top


Status

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

↑ Back to the top


References

Learn about the terminology that Microsoft uses to describe software updates.

↑ Back to the top


Keywords: kb, kbautohotfix, kbqfe, kbhotfixserver, kbfix, kbexpertiseinter, kbsurveynew, kbbug

↑ Back to the top

Article Info
Article ID : 2956241
Revision : 1
Created on : 1/7/2017
Published on : 5/20/2014
Exists online : False
Views : 167