SPARC Enterprise

The SPARC Enterprise series is a range of UNIX server computers based on the SPARC V9 architecture. It was co-developed by Sun Microsystems and Fujitsu, and introduced in 2007. They were marketed and sold by Sun Microsystems (later Oracle Corporation, after their acquisition of Sun), Fujitsu, and Fujitsu Siemens Computers under the common brand of "SPARC Enterprise", superseding Sun's Sun Fire and Fujitsu's PRIMEPOWER server product lines.

Since 2010, servers based on new SPARC CMT processors (SPARC T3 and later) have been branded as Oracle's SPARC T-Series servers.

The midrange and high-end SPARC64 VI, SPARC64 VII, SPARC64 VII+ processor based servers are designated "M-series". The "M" indicates RAS features similar to mainframe class machines.

The SPARC64 VI is a dual-core processor, with each core featuring two-way vertical multi-threading (VMT). A M9000 server configured with the maximum number of processors supports running 256 concurrent threads. VMT is a coarse-grained multi-threading implementation. Each core in the SPARC64 VI can handle two strands or threads. VMT switches execution from one strand to the other on the basis of events. To execute instructions from another thread, the pipeline must be saved/flushed and switched to the registers for the other thread. These events include L2 cache misses, a hardware timer exception, interrupts, or some multi-threading-related control instructions. This is also called Switch On Event (SOE) threading.

In 2008, Fujitsu released the SPARC64 VII, a quad-core processor, with each core featuring two-way simultaneous multi-threading. Existing M-class servers will be able to upgrade to the SPARC64 VII processors in the field.

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