Papyrus A History-based VLSI Design Process Management System

To demonstrate the feasibility of the LWT model, we built a prototype implementation on top of the \fISprite\fR operating system, the Tcl/Tk facility, and the Berkeley OCT CAD tool suite. This implementation features a transparent load balancing scheme to exploit the computation power of networked workstations, an atomicity- guarantee mechanism to preserve the high-level task abstraction. In addition, the rework mechanism depends on a single assignment update principle, which in turn could pose serious storage overheads. Our implementation alleviates this overhead by performing a history-based object reclamation in the background.