Computer Services, Inc.

Legacy Computer Replacement System (LCRS)

LCRS is a drop-in SEL/Gould/Encore computer replacement solution that runs unmodified legacy code using COTS hardware and software, delivering outstanding compatibility, expansion potential and dramatically improved performance at a fraction of the cost and risk of traditional re-hosting.

 

Is your legacy host missing source code?  LCRS comes to the rescue!  In almost all cases, source recompilation is not required, and LCRS will simply run your existing binary code.  LCRS offers extensive tuning options to accommodate virtually any hardware and software characteristic.

 

LCRS is comprised of:

 

1. COTS System Environment (Linux-based hardware and software)

2. COMPRO's Real Time Environment (RTE)

3. COMPRO's LCRS software

 

Each element is further described below.

1. COTS System Environment

LCRS uses Commercial-Off-The-Shelf (COTS) AMD computer systems running the SuSE Linux distribution.  It fully supports most built-in I/O including:

 

  • Gigabit Ethernet (for networking and network printers)
  • PS2 I/O (console keyboard/mouse)
  • Video Out (LCD console)
  • DAT drives
  • Removable hard disk drives

 

Additional I/O controllers (multi-port serial, SCSI, ADI, Encore/SEL/Gould High Speed Device, etc.) are also supported.

 

While COTS offers wonderful performance and maintenance advantages, it also poses long-term supportability risks.  In response, COMPRO's LCRS has migrated from Alpha, SPARC, and Intel based products, demonstrating its portability and largely hardware-independent advantage.  Bottom line – LCRS can "future-proof" your application.

 

2. COMPRO's Real Time Environment

The Real Time Environment (RTE) is a Linux extension (hardware and software) that adds high-performance interrupt latency and determinism to COTS systems.  RTE is included with LCRS to guarantee excellent results.

 

RTE includes:

 

  • PCI Real Time Option Module (PCI-RTOM)
  • Executive Scheduler
  • GUI Performance Monitor
  • Linux Real Time Extensions (RTEX)

 

The RTOM is a central component in virtually all legacy Encore/SEL/Gould computers.  The PCI-RTOM is a plug-compatible replacement for the legacy RTOM. A complete description of the RTE is provided here.

 

3. COMPRO's LCRS Software

LCRS is simply an application that simulates legacy SEL/Gould/Encore computer hardware while retaining inherent system timing.  Regardless of the legacy software (MPX-32 operating system, modified OS, binary code, FORTRAN, etc.), if it ran on legacy hardware, it will run under LCRS.

 

LCRS will run existing binary code.  In situations where source code is lost or indecipherable, LCRS is the only available solution.

 

LCRS uses a simple Linux user-configurable data file to specify system characteristics at runtime.  Elements include memory size, simulated disk pathnames, device handlers and shared memory partition names permitting concurrent LCRS instances on multiple computers.

 

Because legacy code seldom requires modification, LCRS offers the best-value solution when it's time to replace outdated hardware.  Undeniably, re-

writing application code for a new computer system represents enormous risk and cost.  LCRS eliminates these re-hosting downfalls entirely.

 

Input/Output Considerations

Most legacy systems connect with a variety of subsystems using I/O connections such as Ethernet, High Speed Device (HSD), Real Time Option Module (RTOM), Reflective Memory System (RMS), RS-232, etc.  LCRS addresses connectivity to these existing subsystems by offering PCI versions of the legacy controllers.

 

The LCRS design goal is to protect not only your software investment, but to retain, when desirable, existing I/O subsystems.  All the above-mentioned I/O methods can connect to an LCRS bulkhead—using existing I/O cables!  Your subsystems will "never know the difference" and will continue to function as always.

 

Standard legacy peripherals (disk drives, magnetic tape, printers) are easily replaced with compact, modern COTS devices that under-cost, outperform and outlast their legacy counterparts.  And again, they appear functionally identical to your legacy application.

 

Performance Improvement

Additionally, LCRS delivers a dramatic built-in performance boost. LCRS automatically eliminates compute headroom limitations, offering room to grow and smooth operation. LCRS’ performance benchmark data appears below.

Although overall performance is dramatically improved, system timing remains intact.  This is because real time applications are frame-based, and rely upon a system clock (provided by the PCI Real Time Option Module), and still execute at the same frame rate.  However, tasks within the frame execute faster, leaving more "headroom" for additional frame tasks.

 

The benefits are summarized below:

 

  • Executes unmodified legacy applications
  • Uses COTS hardware and software
  • Plugs into existing subsystems
  • Retains legacy timing & improves performance
  • Slashes host replacement costs
  • More maintainable and reliable
  • Reduces risk and speeds deployment
  • Assures compatability and increases frame headroom
  • Flexible expandability with Reflective Memory

 

Industry Acceptance

LCRS has been enthusiastically accepted by military simulation, commercial simulation, range, radar and energy leaders as the smart solution to replace legacy SEL, Gould and Encore hosts.  A partial list of deployments is available here.

 

Additional Information

To download the LCRS white paper, please click here.

 

Pricing Information

Pricing is dependent upon the current system configuration, and is available after a system requirement evaluation.  Please call or email COMPRO to arrange a no-obligation evaluation.

Computer Services, Inc.