Abstract
The Virtual Machine Emulator is an enhanced version of IBM's VM/370 Control Program that extends the virtual machine environment to include timing simulation in addition to the existing simulation of machine function. By selecting processor and I/O device timing characteristics, the user can evaluate the performance of a wide range of 370 compatible systems with greater flexibility and lower cost than hardware prototyping. Validation data are presented showing that the emulator is an accurate performance predictor with a low simulation overhead. © 1980, ACM. All rights reserved.