Scalable Processor Architecture (SPARC)

What is Scalable Processor Architecture (SPARC)?
Scalable Processor Architecture, better known as SPARC, is a RISC (Reduced Instruction Set Computing Computing) technology for microprocessors that was developed by Sun Microsystems and introduced in 1987. It is generally identified with the Solaris Operating System. The SPARC architecture is designed to optimize both 32-bit and 64-bit implementations.
SPARC is a highly scalable open architecture designed for fast execution rates. The word "scalable" in SPARC means that the register stack can be scaled to 512 or 32 windows to minimize processor loads. It can also be scaled down to minimize interference and context switching times.

At any point during a function call, the window 16 registers is passed down the stack to share upper and lower registers between functions. The window moves back up, pushing the local registers to the top or bottom of the stack, allowing local values to be retained across function calls.

There have been several revisions to the SPARC architecture since its release. SPARC introduced many new features in version 8 that include multiplication and division functions, as well as a 128-bit quad precision register.

In addition to Sun Solaris, OpenSolaris and SunOS, SPARC also supports other operating systems such as NetBSD, OpenBSD and Linux.