He's talking simply about clock speed which used to make regular gains with Moore's law but ran up against the heat limits of silicon awhile back. The original

He's talking simply about clock speed which used to make regular gains with Moore's law but ran up against the heat limits of silicon awhile back. The original article that this follows on gives additional background: http://www.gotw.ca/publications/concurrency-ddj.htm http://www.gotw.ca/publications/concurrency-ddj.htm