Exclusive Sun Microsystems has promised a great deal with its futuristic "Rock" processor line but, thus far, failed to back up the promises with any technical details on the chip's design. That situation changes now that The Register has obtained exclusive information pertaining to the Rock chip - or should we say chips - and its related server family. The information in this story has been corroborated by multiple sources.
Now, there's plenty of meat to be had, but we'll feed the core and thread bigots first. The Rock processor - due out in 2008 - will have four cores or 16 cores, depending on how you slice the product. By that, we mean that Sun has divided the Rock CPU into four, separate cores each with four processing engines. Each core also has four FGUs (floating point/graphics units). Each processing engine will be able to crank two threads giving you - 4 x 4 x 2 - 32 threads per chip.
As Sun has long said, Rock will cater to a broader audience than today's UltraSPARC T1 processor that supports 32 threads and the second rev of that product that supports 64 threads. Each of the Rock processing cores will have a higher clock speed than the UltraSPARC T1cores and offer better single thread performance. Sun hopes the Rock chip will please the mainstream Solaris crowd and plans to use the product as a
complement replacement for Fujitsu's version of SPARC that will soon anchor Sun's Unix server line.
Before proceeding with Rock, we'd like to draw your attention to another future addition to Sun's line and another El Reg exclusive.
Sun has started work on a family of UltraSPARC T1 variants that can stand on their own as specialized chips or aid Rock as co-processors.
The main example of this line being talked about is "Jupiter."
Our sources indicate that Jupiter will be built out of four SPARC cores once TI begins churning out 65nm process product. Each core will support eight "vertical" threads.
Overall, Jupiter stands as a type of security and networking dynamo. It's a type of chip Sun and others have long talked about to handle demanding tasks that often pull CPUs away from their main duties.
Jupiter could sit in specialized blade servers, handling key stores, crypto acceleration, and TCP/IP traffic. Or, Jupiter could use direct connect technology to link into a Rock chip and help out with similar workloads.
Moving back to Rock, Sun expects each set of four processing engines to share 32KB of L1 instruction cache and 32KB of L1 data cache. With all 16 processing engines, that's eight cache stores.
The L1 cache then links into a crossbar switch, which Sun seems to think is its special sauce. That crossbar provides four links to four, separate 512KB L2 cache units.
Now for more codename fun.
Sun appears to have a couple flavors of Rock – Pebble and Boulder.
Our information on Pebble is pretty thin, although it appears to be the flavor of Rock meant to sit in one-socket servers. Boulder then powers two-socket, four-socket and eight-socket servers.
The servers have been code-named "Supernova" and appear impressive indeed. A two-socket box – with 32 cores – will support up to 128 FB-DIMMs. The eight-socket boxes will support a whopping 512 FB-DIMMs. Sun appears to have some fancy shared memory tricks up its sleeve with this kit.
The single-socket systems will use a memory controller code-named "Mako," while the multi-processor boxes will use a memory controller code-named "Stingray."
It was way back in 2000 when Sun – with the UltraSPARC III – last garnered any major accolades for its SPARC line. The Rock family and UltraSPARC T1 derivatives may help put Sun back on the innovation map.
In 2008, Intel will be pushing four-core products across its product line, as will AMD. IBM plans to release the dual-core Power6 in 2007 and may well still be on dual-cores in 2008, since Power6 will boast a much higher clock than rival gear.
The chips from Intel, AMD and IBM could knock Rock around on single thread performance. It's hard to say given that our sources have not provided any GHz details on Sun's future chip line.
Sun, however, does seem confident that it can deliver enough single-tread oomph and then clean up on multi-threaded applications by leaping at least a generation ahead of the competition with its multi-core design. Sun has focused on high-bandwidth systems with the Rock design and Supernova systems and will flood these products with data.
Over the past few years, Sun has proven that it struggles with pushing out competitive processors on time. With that in mind, we'll believe our own Rock hype if and only if it appears on schedule in 2008. Should that happen, Rock and friends could once again give Sun a performance edge in the Unix market and let it shine. ®