Microsoft Re-Releases Patches for AMD Bulldozer Architecture
Few weeks back, Microsoft caused a lot of fuss by releasing an incomplete Windows 7 / Server 2008 R2 patch for AMD Bulldozer architecture, which should increase the performance. Download those today.
Several weeks ago, Microsoft caused quite a confusion by releasing a patch that was supposed to increase performance of AMD Bulldozer architecture (FX and Opteron 6200 processors) and its Windows 7 and Windows Server 2008 R2 operating systems.
If you recall, the task scheduler in upcoming Windows 8 operating system properly detects and executes threads on the AMD Bulldozer architecture, while Windows 7 based operating systems do not. However, Microsoft recalled the patch as the release was incomplete and could have caused system instability.
Just as AMD elaborated, there are two patches for the architecture, and they need to be installed in the correct order.
If you own a Bulldozer based system, you have to install in this order:
FIRST INSTALL THIS KB2645594
The CPU scheduling techniques that are used by Windows 7 and Windows Server 2008 R2 are not optimized for the AMD Bulldozer module architecture. Therefore, multithreaded workloads may not be optimally distributed on computers that have one of these processors installed in a lightly-threaded environment. This may result in decreased system performance for some applications. When this update is installed, the scheduler will be aware that your Bulldozer processor contains dual-core modules. In essence, threads 1-4 now get assigned to their own module first.
THEN INSTALL KB2646060
The CPU Power Policies that are used by Windows 7 and Windows Server 2008 R2 are not optimized for the dual core AMD Bulldozer module architecture. This can result in decreased system performance with multithreaded workloads in lightly-threaded environments. When this update is installed, Bulldozer modules will be less likely to achieve the C6 power state. This potentially results in increased power consumption in more lightly-threaded environments.
Let us know in your comments if this patch actually increased the performance of your system or not.