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Emulator Facts

  • A hardware emulator exactly imitates a piece of hardware.
  • A true emulator is binary compatible with the system it is designed to replace.
  • Software can be transferred from legacy hardware to an emulator without modifications.
  • Source code is not required for a successful port to an emulator.
  • Users will be unable to distinguish between applications running on the legacy platform and on the emulator.
  • Virtual systems eliminate legacy hardware costs.
  • Think emulators are new? Check out this 1971 New Scientist article.

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Migration Specialties Virtual Logo

"Hardware virtualization saves time and money. Application ports using hardware emulation can be completed in days. Contrast that with application migration, which at best is a matter of months, or application replacement, which can take years."

Virtual VAX and Alpha Solutions

Retain important software, improve hardware reliability, reduce space, power, and cooling requirements.

Migration Specialties virtual VAX and Alpha solutons allow retention of critical OpenVMS and Tru64 UNIX applications on new Windows hardware without changing the user environment. We provide comprehensive virtual solutions for legacy VAX and and Alpha computer systems manufactured by Digital Equipment Corporation (DEC), Compaq, and HP.

Virtualization Bonus

In addition to the advantages of replacing legacy hardware with new kit, virtualized hardware enables a host of new options. Experimentation, dry-runs, training environments, backup snapshots, and the like all become options with virtualized hardware that were impossible with ageing physical equipment.

Virtual Hardware Advantages

  • Quick implementation.
  • Replaces legacy hardware.
  • Improves system reliability.
  • Improves system performance.
  • Eliminates user retraining.
  • Reduces operating costs.
  • Virtual machine support: VMware®, Sun VirtualBox, Apple Boot Camp, etc.

Let's face it. That old hardware is around because the software it supports is still useful. Virtualizing legacy hardware allows gains in energy efficiency, rack space, and hardware reliability without incurring the costs of software engineering or user retraining. Hardware virtualization allows you to retain critical business applications, extend the life of test stands and tooling, and maintain mandated legacy applications at a low cost. Installation and porting are quick and easy, usually delivered in less than a week.

Virtual Hardware Explained

Software that acts like hardware.

Virtual hardware is a sophisticated computer program that acts like a computer. A virtual system provides all of the hardware interfaces expected by the overlying operating system. In the case of Avanti, everything that OpenVMS or Tru64 UNIX expects is there. Thus, an OpenVMS or Tru64 UNIX system can be ported to Avanti just like they could be ported to a real AlphaServer 400.

Avanti runs as a program on a Windows system. The emulated hardware interface provides access to both virtual and real hardware such as disk drives, CD drives, NICs, and serial ports. The OpenVMS and Tru64 systems running on Avanti are completely unaware they are being hosted on a Windows system. From the OpenVMS or Tru64 perspective, they are running on real Alpha hardware.

The host system is also unaware that it is supporting virtual legacy hardware. Windows just sees a program that uses files and physical devices like any other program. The consequence of this is that for the host system to communicate with the virtual VAX or Alpha system, it must use standard network protocols such as TCP/IP. Hence the recommendation that the host system provide two NICs, one for itself and one to support virtual VAX and Alpha communications.

Virtual system performance is highly dependent upon how the host server is configured. A slow host will adversely impact emulator performance. A fast host will enhance emulator performance. Network and disk I/O present similar issues. Both are typically much faster than legacy VAX and Alpha hardware by virtue of the enhanced speed of modern hardware. However, final performance values are going to be dictated by configuration, network load, I/O load, and CPU speed.

Host CPU speed has a direct correlation to virtual system CPU speed. Everything else being equal, Avanti running on a 3GHz CPU will be 50% faster than Avanti running on a 2GHz CPU. Clock rate, clock multiplier, pipeline size, instruction issue, cache size, and so forth all impact the emulated CPU speed.

Turnkey Solutions

Migration Specialties offers turnkey VAX and Alpha virtualization services. Turnkey services include:

  • Configuration of the replacement system.
  • Transfer of the O/S, applications, and data from the legacy platform.
  • Installation of the new system at your site.

Obtaining a Quote

Hardware and environment information is required before we can quote a replacement package. The information required for each architecture is described at the following links:

If you would like additional information about hardware emulation, give us a call or . We will be happy to help you assess your legacy system replacement options.

OpenVMS Benchmarks

The following code provides basic performance tests for OpenVMS systems. Running these benchmarks unaltered provides a good basis of comparison between systems.

  • PI_TEST.zip
    VMS zip file containing MACRO64$PI source file, PI.EXE executable compiled on VMS 7.3-2, and PI_TEST.COM procedure. The test calculates PI to 40,000 digits and reports the time required in seconds.
    • Note: The PI_TEST.zip file was created using IZIP under VMS. The command used was:
    • $ IZIP "-V" PI_TEST.zip MACRO64$PI.M64 PI.EXE PI_TEST.COM
    • Unzipping the contents of this zip file on a non-VMS system may not produce readable source code. Use the links above to acquire the code on a non-VMS system.
  • VUPS.COM
    A VMS DCL procedure that provides an estimate of CPU performance measured in VUPs.
    • Note: This procedure is suitable for single CPU VAX and Alpha systems. It does not accurately measure the performance of multi-processor systems.
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