Tag Archives: “poor performance”

HTTP and HTTPS requests or traffic to a Windows Vista, Windows 7, Windows Server 2008, SBS 2008, Windows Server 2008 R2 or SBS 2011 machine may exhibit increased latency if the connection is through a network load balancer

If you utilise Microsoft Internet Information Services IIS or an application that uses the System.Net.HttpListener class is installed or running on one the operating systems below, and you have a Network Load Balancer then you may find that Increased latency occurs on HTTP and HTTPS requests and traffic.

This issue occurs because the HTTP and HTTPS requests from clients can include zero length data in the SSL records, certain server-side variables do not update correctly in this instance and Http.sys leaves the connection in the CLOSE_WAIT state.  This intern exhausts the open connection limit can introduce latency, timeouts and connection problems.

Affected Operating Systems:

Microsoft Windows Vista

Microsoft Windows 7

Microsoft Windows Server 2008

Microsoft Small Business Server 2008 – SBS 2008

Microsoft Windows Server 2008 R2

Microsoft Small Business Server 2011 – SBS 2011

The Microsoft Knowledge Base Article KB 2634328 includes further information on this issue and provides an updated version of Http.sys that corrects the issue http://support.microsoft.com/kb/2634328

Microsoft Windows may stop responding or respond very slowly when the .Net Framework 4 Optimization Service (Mscorsvw.exe) starts

The computer may stop responding or respond very slowly when the .Net Framework 4 Optimization Service (Mscorsvw.exe) starts. This issue effects the following operating systems: Windows XP SP3, Windows Server 2003, SBS 2003, Windows Vista SP2, Windows Server 2008 SP2, SBS 2008 SP2, Windows 7 SP1, Windows Server 2008 R2 SP1 and SBS 2011 SP1.

The issue occurs because the process sets its service configuration incorrectly.

A hotfix is available but must be requested from Microsoft using KB 2571181 http://support.microsoft.com/kb/2571181

Alternatively you can immediately download the hotfix from “thehotfixshare” website

Windows x86


Windows x64


Windows Vista, Windows Server 2008 and SBS 2008 with Service Pack 2 – You may find that applications stop responding, delays occur during resume from standby and/or files may become corrupt when the computer goes to sleep/hibernate and/or poor AMD processor/chipset performance

A variety of issue exist post service pack 2 with Windows Vista, Windows Server 2008 and Small Business Server 2008, a variety of hotfixes have been released since 2008 to address these issues but you only need to apply the latest to ensure that all subsequent issues are addressed.


You should only need to apply the hotfix from KB 980080 to ensure that all the issues below are addressed as this contains the latest versions of the affected files, this can be obtained from http://support.microsoft.com/kb/980080


KB 980080 – Files may be corrupted when a computer that is running Windows Vista or Windows Server 2008 enters the sleep mode or the hibernate mode

Info: http://support.microsoft.com/kb/980080

KB 977323 – After you change the SATA mode of disk devices to use the AHCI specification on a Windows Server 2008-based or Windows Vista-based computer, the computer or certain applications randomly stop responding for 60 seconds or longer

Info: http://support.microsoft.com/kb/977323

KB 974073 – An update for the Msahci.sys driver has been released for AMD chipsets

Info: http://support.microsoft.com/kb/974073

KB 971390 – A minor delay occurs when Windows Vista or Windows Server 2008 resumes from sleep if the hard disk is attached to a secondary ATA port

Info: http://support.microsoft.com/kb/971390

Windows Server 2008 R2 and SBS 2011 RTM or SP1 – You may experience disk I/O performance issues with certain Intel Xeon Processors

You may experience disk I/O performance issues if your server contains an Intel Xeon Westmere-EX (10 Core) processor

This can occur because some of the I/O completion port objects are not cache-aligned. This behavior is what causes poor disk I/O performance.

You can resolve the issue by updating Ntoskrnl.exe and Ntkrnlpa.exe updated versions are available for download from http://support.microsoft.com/kb/2545635