14-09-2017, 02:13 PM
Hyper-Threading (officially known as Hyper-Threading Technology or HT Technology) is Intel's proprietary multithreading (SMT) implementation, used to improve parallelization of computations (multitasking at the same time) in x86 microprocessors. It first appeared in February 2002 on Xeon server processors and in November 2002 on Pentium 4 desktop CPUs. Later, Intel included this technology on Itanium, Atom and Core 'i' CPUs, among others.
For each processor core that is physically present, the operating system addresses two virtual (logical) cores and shares the workload between them when possible. The main function of hyper-threading is to increase the number of independent instructions in the pipe; takes advantage of the superscalar architecture, in which multiple instructions operate on separate data in parallel. With HTT, a physical core appears as two processors to the operating system, allowing concurrent programming of two processes per core. In addition, two or more processes can use the same resources: if resources for one process are not available, then another process can continue if its resources are available.
In addition to requiring simultaneous multi-threading (SMT) support on the operating system, the hyper-threading can be used correctly only with an operating system specifically optimized for it. In addition, Intel recommends HTT to be disabled when operating systems are not aware of this hardware feature.
For each processor core that is physically present, the operating system addresses two virtual (logical) cores and shares the workload between them when possible. The main function of hyper-threading is to increase the number of independent instructions in the pipe; takes advantage of the superscalar architecture, in which multiple instructions operate on separate data in parallel. With HTT, a physical core appears as two processors to the operating system, allowing concurrent programming of two processes per core. In addition, two or more processes can use the same resources: if resources for one process are not available, then another process can continue if its resources are available.
In addition to requiring simultaneous multi-threading (SMT) support on the operating system, the hyper-threading can be used correctly only with an operating system specifically optimized for it. In addition, Intel recommends HTT to be disabled when operating systems are not aware of this hardware feature.