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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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"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 Overview

Migration Specialties provides comprehensive software, installation, and porting solutions for legacy DEC VAX and DEC/Compaq/ HP Alpha computer systems. We take the mystery out of replacing legacy VAX and Alpha hardware.

Virtualization Bonus

In addition to the obvious 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 easily implemented options with virtualized hardware that were simply 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.

Without changing the user environment, Migration Specialties virtualization solutions improve hardware reliability while reducing space, power, and cooling requirements.

Out with the Old Hardware; Keep the Important Software

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.

What is a Hardware Emulator?

Migration Specialties virtual systems use a sophisticated program to emulate legacy hardware. Our virtual VAX and Alpha solutions duplicate legacy hardware at the machine code level. This allows legacy applications to be run on a modern server without recompilation. Software emulators do not require any special hardware to operate and take full advantage of modern hardware and VM technology.

In simple terms, a legacy hardware emulator like Avanti is a self contained program that provides all of the interfaces a legacy O/S and its applications expect. As such, an emulator can fully replace physical hardware. Avanti runs as a program on a Windows system. It presents a valid hardware interface to the OpenVMS and Tru64 UNIX operating systems. 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 much 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 or Alpha communications.

Virtual VAX and Alpha 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 VAX and Alpha 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, making performance a complex issue.

Virtual Machines

Migration Specialties' virtual VAX and Alpha solutions are fully supported in virtual environments. Our products are in active use running on VMware®, Sun VirtualBox, and Apple Boot Camp virtual systems.

Legacy Liabilities

Many legacy computers continue to serve useful functions running specific business applications or servicing specialized hardware such as probes and sensors. However, time is everyone's nemesis and hardware is no exception. Legacy hardware has the following liabilities:

  • Poor reliability due to age.
  • High maintenance costs.
  • Lack of parts and service.
  • Large physical size.
  • Heavy power consumption and heat generation.

Modern servers are smaller, faster, and more efficient. The problem is they don't support software running on the legacy platform; software you rely on to run your business. The best solution would be a new computer that runs the legacy O/S and supports the legacy bus structure. Unfortunately, Digital Equipment Corporation is a page in the history books. Migration Specialties has filled the gap, providing the means to move to new hardware without changing software or operations procedures.

Turnkey Solutions

Migration Specialties offers legacy hardware virtualization services covering VAX and Alpha systems. 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.

More information is available on the Emulator Services page.

Obtaining a Quote

Before we can quote an replacement package, you will need to provide information covering your hardware configuration and operating environment. 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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