Virtual Iron reports that new virtualization enhancement included in Intel Xeon 7300, VT FlexPriority, brings a performance improvement up to 35% in a system with Virtual Iron 4.0 and 32bit Windows guest operating systems. Some details provided by official announcement:
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Intel® VT FlexPriority optimizes and accelerates interrupt virtualization by improving virtual machine access to the Task Priority Register thereby enabling efficient Symmetric Multi-Processing (SMP) configurations of 32-bit guest operating systems. For users, this translates into more efficient performance in virtual environments for their critical enterprise applications.
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Intel VT FlexPriority was designed to accelerate virtualization interrupt handling thereby improving virtualization performance. Intel VT FlexPriority accelerates interrupt handling by preventing unnecessary VMExits on accesses to the Advanced Programmable Interrupt Controller…