Intel® Simics® Simulator for Intel® FPGAs: User Guide

ID 784383
Date 12/04/2023

A newer version of this document is available. Customers should click here to go to the newest version.

Document Table of Contents

5.5. Intel® Simics® Simulator Timing

When referring to timing in Intel® Simics® simulator, it is necessary to make a difference between real time and virtual time. Real time is the time that you perceive in the real world, and this can be related to how the real hardware behaves. Now, virtual time is related to the perception about how the Intel® Simics® simulation is progressing. During a simulation, Intel® Simics® simulator does not attempt to synchronize virtual time with real time by default as this breaks determinism and repeatability (the virtual time is included as part of the state to save with checkpoints).

In real hardware, the instruction execution time depends on memory access latencies, the complexity of the operation, execution resource contention, etc. These things are not simulated by default but. Instead, all the operations needed to execute one instruction are executed in one single transaction.

The following sections describe some timing concepts that allow you to understand the Intel® Simics® simulator timing model: