Accelerating Excel® 2010 with Windows® HPC Server 2008 R2: Converting Cluster-Safe UDFs for Offloading to a Windows® HPC Cluster

This article and accompanying code samples address how to convert convert an existing XLL file to enable offloading to a Windows HPC 2008 R2 cluster. The article also explains how UDF offloading works, performance considerations, and how to determine if a UDF is appropriate for cluster offloading.
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    August 2010

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    380 KB

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      Note: Article and samples were updated for this release of Windows HPC 2008 R2. For more information about updating Excel solutions from Beta 2 , see the Excel Workbook Offloading Beta Transition Guide.

      Microsoft Excel 2010 extends the UDF model to the cluster by enabling Excel 2010 UDFs to run in a Windows HPC 2008 R2 cluster. In the cluster, UDFs work much like traditional UDFs, except that the calculation is performed by one or more servers. The key benefit is parallelization. If a workbook contains calls to long-running UDFs, multiple servers can be used to evaluate functions simultaneously.

      In order to run on the cluster, the UDFs must be evaluated as appropriate for a cluster, marked as cluster-safe, and then the XLL file must be recompiled. This article walks through an example of how to convert an existing XLL file. The article also explains how UDF offloading works, performance considerations, and how to determine if a UDF is appropriate for cluster offloading..

      The associated zip file includes:
      • Solutions for Visual Studio 2008 and Visual Studio 2010 for the sample XLL
      • Two sample securities pricing workbooks that uses the UDF in the sample XLL
      • XLL SDK files to support the sample code

      Note: The workbooks contain macros. When you open the workbook, you may see a security warning indicating that the macros have been disabled. You can enable the macros by clicking "Enable Content".

      Note: Microsoft provides programming examples for illustration only, without warranty either expressed or implied, including, but not limited to, the implied warranties of merchantability and/or fitness for a particular purpose.

  • System Requirements
    Supported Operating System

    Windows HPC Server 2008 R2

      Microsoft Word of Word Viewer, Microsoft Excel 2010, Windows HPC Server 2008 R2 cluster, Visual Studio 2008 or 2010
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