Yesterday, Microsoft Support site released KB2592546, a hotfix download with the following description:
"An update to optimize the performance of AMD Bulldozer CPUs that are used by Windows 7-based or Windows Server 2008 R2-based computers is available."
This is the download a lot of users of AMD FX and Opteron 6200 Series processors are expecting. The problem between Microsoft and AMD appeared when AMD launched its desktop and server processors based on the Bulldozer architecture. The processors are specifically optimized for Windows 8 task scheduler, but the Task Schedulers for Windows XP, Vista and current Windows 7-based operating systems just cannot take full advantage of the Bulldozer architecture.
This naturally resulted in lower performance scores. To fix the situation, Microsoft released the afore mentioned KB2592546 patch which describes itself as:
"An update that optimizes the performance of AMD Bulldozer CPUs that are used by Windows 7-based or Windows Server 2008 R2-based computers. Currently, the performance of AMD Bulldozer CPUs is slower than expected. This behavior occurs because the threading logic in Windows 7 and in Windows Server 2008 R2 is not optimized to use the Simultaneous Multithreading (SMT) scheduling feature. This feature was introduced in the Bulldozer family of AMD CPUs. "
However, less than 24 hours after introduction, Microsoft pulled the patch. We contacted AMD and Microsoft and received an answer from AMD first. For starters, AMD was surprised that Microsoft decided to post the patch in its current form, because:
"there are actually two updates needed for AMD Bulldozer CPU architecture. Microsoft posted just the first patch and we do not believe users would benefit in any way from it. The patch was originally scheduled for the first quarter 2012 and then the users will see tangible performance benefits when using Windows 7 and Windows Server 2008 R2 operating systems."
There you have it folks, Microsoft jumped the gun and released an incomplete update. We’ve been told that the official statements regarding this patch will be released by both AMD and Microsoft in due course.