Windows HPC Server 2008

Windows HPC Server 2008, released by Microsoft on 22 September 2008, is the successor product to Windows Compute Cluster Server 2003. Like WCCS, Windows HPC Server 2008 is designed for high-end applications that require high performance computing clusters (HPC stands for High Performance Computing). This version of the server software is claimed to efficiently scale to thousands of cores. It includes features unique to HPC workloads: a new high-speed NetworkDirect RDMA, highly efficient and scalable cluster management tools, a service-oriented architecture (SOA) job scheduler, an MPI library based on open-source MPICH2, and cluster interoperability through standards such as the High Performance Computing Basic Profile (HPCBP) specification produced by the Open Grid Forum (OGF).

In June 2008, a system built collaboratively with the National Center for Supercomputing Applications (NCSA) and Microsoft ranked #23 on the TOP500 list, a ranking of the world's fastest supercomputers, with a LINPACK score of 68.5 teraflops. The NCSA supercomputer uses both Windows Server HPC and Red Hat Enterprise Linux 4. As of November 2011, that ranking has since dropped to #253.

In the November 2008 rankings, published by TOP500, a Windows HPC system built by the Shanghai Supercomputer Center achieved a peak performance of 180.6 teraflops and was ranked #11 on the list. In June 2015, that was the only Windows machine left then ranked 436, just barely made the TOP500 (with Windows Azure dropping off earlier), and in November 2015 it dropped off the list with then all the machines on the list running on Linux (98.8%) except for six AIX Unix machines, where the top ranked of the latter at number 208.

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