I have been working with computer simulation and computer architecture for more than 20 years, and one thing that has been remarkably stable over time is the simulation slowdown inherent in “cycle accurate” computer simulation. Regardless of who I talked to or what they were modeling, the simulators ran at around 100 thousand times slower than the machine being modeled. It even holds true going back to the 1960s! However, there is a variant of simulation that aims to make useful performance predictions while running around 10x faster (or more) – mechanistic models (in particular, the Sniper simulator).Continue reading “Simulating Computer Architecture with “Mechanistic” Models – No more 100k Slowdown?”
This is a short maybe heretic post on the topic of architecture exploration.
It just struck me the other day that the idea prevalent in chip design that you want to explore the design space of a certain with great detail and precision might be the wrong way to go about things. It is in some sense similar to the ideas of planned economies: you decide a priori what is important, and try to optimize the design to do just that. If you are right, it is brilliant. If you are wrong, it can be very wrong. That is scary to say the least. It seems to assume that you have a pretty good idea of what you need to achieve, and that this is not likely to change for the lifetime of a design.