Resource Logic Client/Server Development Services

Project - Technical Publications Warehouse

The US Air Force maintains technical order warehouses at maintenance depots throughout the United States. These warehouses contain the maintenance and repair manuals for aircraft, ground support equipment, and other vehicles in use on a long term basis.

An existing application had been written in Foxpro 2.6 for Windows and SQL-Server 6.5 on NT Server. This system had been in use since 1995 operating on 486 based workstations and a 120Mhz, 64Mb(RAM) server. The performance of this system was sufficiently constrained that it had been necessary to divide the day into two activity phases, because certain processing functions were so slow that other operations were brought to a standstill.

The three primary issues confronting the users were the speed of the system, bugs, and Y2K compliance. The system had been maintained by a number of programmers over time, and as a result it generated error conditions that users had to work around. Users typically spent several minutes per order simply clicking through error message boxes. Label printing was sufficiently clumsy that large label print runs had to be restarted from scratch if some fault developed during the print run.

The solution evident to us was to rewrite the system in Visual Basic, since this was a full 32-bit system and would make better use of the 486 processors. After two months of development, we invited the warehouse people over for a demo. The performance results were a disappointment.

Placing more RAM in the existing server improved speed, although not by much. We estimated at that point that more appropriate processing hardware would consist of a server with at least 800 Mips effective processing power and enough RAM to contain the entire database in memory. We configured and installed a Dell 6300 with dual 400 Mhz processors, 512Mb of RAM, and a five drive RAID. This solution improved performance markedly and the operational bottlenecks were largely eliminated.

We continued development on the Visual Basic system, first because the Foxpro database in use was no longer supported by Microsoft, and second because there were changing requirements elsewhere in the organization that would have to be addressed. The workstations, in the meantime, were replaced with Pentiums in order to deal with networking performance and Y2K issues.

The system that we implemented was interoperable with the Foxpro system (since both used SQL-Server), so there was no parallel operations. As we brought on new functionality, the older programs simply fell into disuse.

Kelly AFB was the original user of this system, however Kelly has closed. This system is now in use at Warner/Robins, Tinker, and Hill AFBs.

This work was done by one of us as an employee of Datavise Engineering Services. Resource Logic, Inc. was not and is not a contractor or subcontractor to the US Air Force.