I dug into the 50× claim in <a href="https:&#x2F;&#x2F;www.mail-archive.com&#x2F;kragen-tol@canonical.org&#x2F;msg00185.html" rel="nofollow">https:&#x2F;&#x2F;www.mail-archive.com&#x2F;kragen-tol@canonical.org&#x2F;msg001...</a>.  Basically Alan was saying that the all-ECL Dorado, which was never sold commercially but might have cost US$100k per computer if it had been, was 50× slower than modern (2005) embedded RISC processors that cost US$150 per computer.<p>Omitting the three orders of magnitude in performance due to sheer brute cost is how you get to &quot;only 50 times faster today&quot;.  There&#x27;s an additional order of magnitude of overhead in Squeak&#x27;s bytecode-interpretation strategy, which was a good strategy on the Dorado but not on an AMD64; you can squeeze that out with JIT, and you get to four orders of magnitude discrepancy between Kay&#x27;s offhand claim and reality.  If you build a 500-node cluster and use a modern JIT compiler on it, the &quot;efficiency that has been lost by bad CPU architectures&quot; evaporates.<p>As you implicitly point out, though, this is parallel performance, not serial performance.<p>Kay&#x27;s group has done a substantial amount of awesome research since he said that in 2007, dramatically exceeding Kay&#x27;s expectations for performance on modern machines.  To a great extent, Kay&#x27;s Communication Design Group (funded by VPRI and SAP) is the closest thing we have today to the 1970s Xerox PARC, pioneering new enabling technologies and interaction paradigms.