Multicore Software Challenges

David Grove (IBM)

Mainstream computer venders have announced two dramatic changes in their future architectures. First, in most cases, the increase in clock frequency we've experienced over the past decades will cease to continue and the relative amount of cache memory per processor will decrease. Second, there will be exponentially increasing number of processor cores on a chip. These changes present two unprecedented challenges to the software stack. Namely, how does the software 1) deal with the stagnation of single threaded performance and cache memory, and 2) utilize the additional capabilities provided by multiple cores on a chip? In this talk, I will discuss these issues and suggest some approaches to address these fundamental problems. I will also highlight some of the programming language research efforts at IBM Research that are addressing aspects of this challenge.