QuickTransit supports multiple threads and performs very well on systems with multi-core CPUs. Since many of our customers migrate applications from legacy Solaris/SPARC servers that may be five or more years old (with UltraSPARC II processors running at a few hundred MHz), they generally find that those migrated applications run two to four times faster on a current x86-based server with dual-core or quad-core CPUs (typically running at several GHz clock speed). So in other words, the performance benefits of the latest x86 hardware far outweigh the virtualization overhead imposed by QuickTransit and VMware, which each add a (thin) abstraction layer.

Of course, if the same Solaris/SPARC application were available natively compiled for new Sun servers running the very latest and most powerful SPARC processors, then it would perform better natively than running via QuickTransit virtualization. But most of our customers find themselves in a situation where the applications they have, for one reason or another, will not run on the new-generation SPARC-based servers, without a considerable porting and recompilation effort. In some cases, the source code has been lost altogether, which means that recompilation is no longer an option.