Sun officials still won't say a heck of a lot about the upcoming Niagara processor family, despite the fact that our sources have it shipping in just a couple of months. Thanks to some beta systems and OpenSolaris, however, the Average Joe can discover a thing or two about these multicore chips.
Sun has positioned Niagara-based systems as low-end to midrange Xeon server killers. This may sound like a familiar pitch - Sun used it with the much delayed UltraSPARC IIIi processor. This time around though Sun seems closer to delivering on its promises by shipping an 8 core/32 thread chip. It's the most radical multicore design to date from a mainstream server processor manufacturer and arrives more or less on time.
Even though it remains shrouded in mystery, Niagara does have a few clear attributes that have been discussed in public. Namely, the chip's design makes up for the gap between processor and memory performance. When a thread hangs the pipeline, another software thread comes to the rescue and keeps the processor working. This approach counters less artistic solutions from, say, Intel, which just straps a giant cache onto its speedy single core chips. The design also reduces the need for more complex branch prediction, out-of-order execution and other techniques chip designers have tried in recent years. Sun argues that Niagara and Rock are cleaner and simpler.
By using a couple of commands and looking at the OpenSolaris code, observers would seem to be able to tell the Niagara chip's first name and clock speed, along with future directions for the chip. (Thanks and thanks again, RSM.)
$ ./psrinfo -vp
The physical processor has 8 cores and 32 virtual processors
The core 0 has 4 virtual processors (0, 1, 2, 3)
The core 1 has 4 virtual processors (4, 5, 6, 7)
The core 2 has 4 virtual processors (8, 9, 10, 11)
The core 3 has 4 virtual processors (12, 13, 14, 15)
The core 4 has 4 virtual processors (16, 17, 18, 19)
The core 5 has 4 virtual processors (20, 21, 22, 23)
The core 6 has 4 virtual processors (24, 25, 26, 27)
The core 7 has 4 virtual processors (28, 29, 30, 31)
UltraSPARC-T1 (clock 1080 MHz)
UltraSPARC-T1 is listed as the Niagara CPU module in plenty of Sun documentation that we found on its web site and in the Solaris code. Sun typically identifies the CPU modules with their marketing names, so it's pretty safe to bet that you'll be reading a lot more about the UltraSPARC-T1 in the coming months. In addition, Sun mentions the UltraSPARC-H20 systems as being multicore products similar to the UltraSPARC-T1. Sadly, there is far less detail about the UltraSPARC-H20 products, and some Sun insiders we talked to haven't even heard of this product. So, it may be an old name or just a beta box.
The first server based on the Niagara chip is believed to be called the Sun Fire T200.
Should this documentation match Sun's launch plans, then we're looking at a chip with 1.08GHz cores. A Sun insider, however, cautioned that numerous beta boxes have reached customers with the Niagara chips running at different speeds and added that the company hasn't settled on a launch speed just yet. Still, this speed has to be considered in the ballpark.
Such a frequency fits with Sun's plan to pack server racks full of these low-power processors. Sun wants Niagara to power thin servers that are chock full of memory and that can crank through highly threaded software workloads such as web and application server software.
Looking forward, it seems Sun has already made plans for at least a 64-thread version of Niagara. A 16 core/4 thread design would seem to be the most likely option for Niagara II. This snippet of source code shows,
60 * Maximum cpuid value that we support. NCPU can be defined in a platform's
61 * makefile.
63 #ifndef NCPU
64 #define NCPU 64
To do some digging of your own, chuck in the Niagara servers' codename - Ontario - or their "sun4v" designation into the source code search.
While this information might be of some help to Sun customers, a number of you have complained about the thin roadmap surrounding both Niagara and the Rock family of processors. Sun executives were very vocal early on about their intentions to head the multicore route but have been less forthcoming with CPU specifics. The enterprise customers that Sun desperately wants and needs to hang on to could use a more concrete view of the future. Lord knows, we'd like to see some details.
With the Niagara launch just months away, Sun has a real chance to put pressure on rivals IBM and Intel. It's been a long time since Sun could claim an advance over the competition in the RISC market.
Intel, however, isn't sitting still and will largely copy much of Sun's approach in 2007 and 2008 with a massive fleet of multicore server processors. For its part, IBM has BlueGene.®