Sun Microsystems' UltraSPARC T2 microprocessor is a multithreading, multi-core CPU. It is a member of the SPARC family, and the successor to the UltraSPARC T1. The chip is sometimes referred to by its codename, Niagara 2. Sun started selling servers with the T2 processor in October 2007.

New features

The T2 is a commodity derivative of the UltraSPARC series of microprocessors, targeting Internet workloads in computers, storage and networking devices. The processor, manufactured in 65 nm, is available with eight CPU cores, and each core is able to handle eight threads concurrently. Thus the processor is capable of processing up to 64 concurrent threads. Other new features include:

Core pipeline

There are 8 stages for integer operations, instead of 6 in the T1.

Systems

The T2 processor can be found in the following products from Sun and Fujitsu Computer Systems: Sun also licensed the T2 processor to Themis Computer, which introduced the first non-Sun T2-based servers in 2008:

UltraSPARC T2 Plus

In April 2008, Sun released servers based on the UltraSPARC T2 Plus processor, an SMP capable version of UltraSPARC T2. Sun released the UltraSPARC T2 Plus processor with the following changes:

T2 Plus systems

UltraSPARC T2 Plus processors can be found in the following products from Sun and Fujitsu Computer Systems: Two-way SMP servers: Four-way SMP server:

Compute cluster

The High Performance Computing Virtual Laboratory in Canada built a compute cluster using 78 Sun SPARC Enterprise T5140 servers. With two 1.2 GHz T2 Plus chips in each T5140 server, the cluster has close to 10,000 compute threads, making it ideal for high-throughput workloads.

Virtualization

Like the T1, the T2 supports the Hyper-Privileged execution mode. The SPARC Hypervisor runs in this mode and can partition a T2 system into 64 Logical Domains, and a two-way SMP T2 Plus system into 128 Logical Domains, each of which can run an independent operating system instance.

Performance improvement versus T1

The UltraSPARC T2 offers a variety of performance improvements over the former UltraSPARC T1 processor Other UltraSPARC T2 performance related tunings are documented on Oracle engineers' blogs.

Power consumption

Peak power consumption can go as high as 123 watts, but the T2 typically consumes 95 watts during nominal system operation. This is up from 72 watts from the T1. Sun explains that this is due to a higher degree of system integration onto the chip.

Release history

On April 12, 2006, Sun announced the tape-out of the UltraSPARC T2. Sun announced the T2's release on 7 August 2007, billing it as "the world's fastest microprocessor". On April 9, 2008, Sun announced the UltraSPARC T2 Plus.

Open design

On December 11, 2007, Sun made the UltraSPARC T2 processor design publicly available under the GNU General Public License via the OpenSPARC project. The release includes: