Some Reeections on Computer Engineering: 30 Years after the Ibm System 360 Model 91

I am very pleased to address the MICRO conference on the occasion of its 30th anniversary, and to speak to you about the IBM System 360 (S/360) Model 91, which also celebrates the 30th anniversary of its rst shipment. I will describe rst the background to the project, then the machine itself; in the second half of my talk I will share some re ections on the changes in computer engineering over this time. Before going further, I would like to dedicate these remarks to the designers of the S/360 Model 91 machine and its derivative, the S/360 Model 195, and also to the designers of the CDC 6600 and its derivative, the CDC 7600. The CDC 6600 machine was for the S/360 Model 91 a very important competitive machine. I believe this competition pushed both projects to achieve excellence within the context of the technology of the day.