Sun's Ultrasparc T1 And T2 Processors - The Dawn Of Massively Multithreaded Computers

Sun Microsystems's new UltraSPARC T1 and T2 series of microprocessors has revived Sun's position as one of the few third party manufactures capable of contesting with the massive two processor firms who currently dominating the processor market. Sun slid behind for a few years as their flagship processor, the UltraSPARC IV series, hit its performance limits. But they have reentered the competition with their new UltraSPARC processors, completely re-designed from the bottom up, and capable of new heights of power and pliability.

The UltraSPARC T1 is the 1st processor produced by Sun that's both multicored and multithreaded. It first became available in 2005 with from 4 to 8 CPU cores. Each core is capable of handling four threads at the same time. This suggests the processor in total is really capable of handling anywhere from 16, 24, or 32 threads concurrently.

The UltraSPARC T1 is the first SPARC-based processor whose multiple cores can be partitioned. A few cores can be grouped together to work on a single task or set of tasks, while the leftover cores deal with the remainder of the processes and threads. Additionally, the UltraSPARC T1 supports the Hyper-Privileged execution mode, which implies that it can partition its cores into as much as 32 logical domains ( one for each thread in an eight-CPU system ). Each one of these logical domains could run its own O. S example ( usually Solaris ).

The sole drawback to the UltraSPARC T1 is that it is only available in uniprocessor systems, which boundaries its vertical scalability in large business networks. The UltraSPARC T2, released in late 2007, addressed his problem amidst lots of other advances and improvements.

The UltraSPARC T2 is in some ways a souped-up T1. It contains 8 CPU cores, and each core is able on handling eight threads each, for a total of 64 threads being handled simultaneously. This is double the maximum capacity of the T1, which toped out at 32 simultaneous threads. Also like the T1, the T2 supports Hyper-Privileged execution mode. Whereas the T1 could only partition its cores into 32 logical domains, the T2, with more cores available, can partition them into 64 logical domains. Additionally, a two-way SMP T2+ system can be partitioned into as many as 128 logical domains, each capable of running an instance of Solaris.

In addition to doing everything the T1 does ( only better ), the T2 also had several new features. Among other things, it had increased thread scheduling and instruction prefetching, allowing it to attain a higher single-threaded performance. It also increased the processing speed for each thread from 1.2 for the T1 to 1.4 GHz. While the T1 has a Jbus interface, the T2 has a PCI Express port. The L2 cache on the T2 was increased to 4 MB ( vs the T1's three MB ). It has 4 dual-channel FBDIMM memory controllers, and eight encryption engines. In early 2008, Sun released a new UltraSPARC T2 plus processor, which is an SMP-capable version of the UltraSPARC T2.

Sun MicroSystems' UltraSPARC T1 and T2 prove that, in spite of accelerating competition from Intel and AMD, Sun is still in the processor race, particularly in the top-end server processor market. Sun's designs remain cutting edge and, as the core partitioning system demonstrates, flexible.