The Intel Xeon processor introduces a new technology called Hyper-Threading (HT) that, to the operating system, makes a single processor behave like two logical processors. When enabled, the technology allows the processor to execute multiple threads simultaneously, in parallel within each processor, which can yield significant performance improvement. We set out to quantify just how much improvement you can expect to see.
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The existence of Hyper-Threading support can be seen by using the command cat /proc/cpuinfo to show the presence of two processors, processor 0 and processor 1. Note the ht flag in Listing 1 for CPUs 0 and 1. In the case of no Hyper-Threading support, the data will be displayed for processor 0 only.