NEC SX

The first models, the SX-1 and SX-2, were announced in April 1983, and released in 1985. The SX-4 series was announced in 1994, and first shipped in 1995. Since the SX-4, SX series supercomputers are constructed in a doubly parallel manner. A number of central processing units (CPUs) are arranged into a parallel vector processing node. These nodes are then installed in a regular SMP arrangement. The SX-5 was announced and shipped in 1998, Tadashi Watanabe has been NEC's lead designer for the majority of SX supercomputer systems. For this work he received the Eckert–Mauchly Award in 1998 and the Seymour Cray Computer Engineering Award in 2006. ==Hardware==

CPU architecture The NEC SX Vector Engine (VE) is a vector processor, and each VE core has a Scalar Processing Unit (SPU) with 64 scalar registers of 64 bits, and a Vector Processing Unit (VPU) with 64 vector registers (of up to 256 bits in the SX-Aurora TSUBASA). The SPU implements in hardware the IEEE 754's quadruple-precision floating-point format, and every instruction is 64-bit long. SX systems Each system has multiple models, and the following table lists the most powerful variant of each system. Further certain systems have revisions, identified by a letter suffix. ==Software environment==

Operating system The SX-1 and SX-2 ran the ACOS-4 based SX-OS. The SX-3 onwards run the SUPER-UX operating system (OS); the Earth Simulator runs a custom version of this OS. Compilers SUPER-UX comes with Fortran and C++ compilers. Cray has also developed an Ada compiler which is available as an option. Software Some vertical applications are available through NEC, but in general customers are expected to develop much of their own software. In addition to commercial applications, there is a wide body of free software for the UNIX environment which can be compiled and run on SUPER-UX, such as Emacs, and Vim. A port of GCC is also available for the platform. SX-Aurora TSUBASA The SX-Aurora TSUBASA PCIe card is running in a Linux machine, the Vector Host (VH), which provides operating system services to the Vector Engine (VE). The VE operating system VEOS runs in user space on the VH. Applications compiled for the VE can use almost all Linux system calls, they are transparently forwarded and executed on the VH. The components of VEOS are licensed under the GNU General Public License. ==References==