A class action lawsuit against AMD claiming that the company misrepresented its bulldozer's capabilities Bulldozer-derived product lines will be brought to trial after a federal district judge has ruled While it does not dismiss them, while US District Judge Haywood Gilliam does not make a decision in favor of the plaintiff, the class action lawsuit is admitted and can proceed.
Claimant Tony Dickey and Paul Parmer argue that AMD misrepresented the number of core processors in its bulldozer. Line of Central Processing Unit … Plaintiffs allege that the Bulldozer CPUs announced with eight cores actually have eight & # 39; subprocessors & # 39; that share resources, such as L2 memory caches and floating point units (& # 39; FPUs & # 39;). "
I wrote about this lawsuit when it was filed in 2015, and my opinion has not changed in the last three years." This article also looks at the specific allegations that Dickey made in his original case against AMD and why they were in some ways inaccurate or inapplicable, in which case AMD's claim that "a significant majority interprets the core in a way that fully complies with AMD's chips" was considered inadequate, The Dickey and Parmer actually argue that Bulldozer / Piledriver (specifically the FX-9590) did not perform as well as they did from an eight-core CPU Intel CPUs expected . They argue that the shared resources in bulldozer ke It prevented the chip from "simultaneous multitasking," and Bulldozer "functionally consists of only four cores" because resources were shared between the CPU cores. Both claims are in fact wrong. 19659004] Bulldozer does not support SMT, which allows one CPU to run more than one thread at a time. The fact that performance in integer and FPU workloads on a BD / PD processor increases when transitioning from four to eight threads is evidence that the CPU is not limited to a functional quad core arrangement. As these results from OpenBenchmarking.org show, BD performance improves beyond the four-thread mark, even with FPU workloads. Integer workloads also show improvements in scaling four threads to eight. While the absolute scaling level may be lower, Bulldozer is not a functional quad-core CPU in terms of the defined core number. The fact that its overall performance may correspond to an Intel quad-core has nothing to do with whether the CPU actually had the specified number of cores.
It's Absolutely true that Bulldozer's scaling factor was about 20 percent lower than a "true" multi-core design. It's also true that AMD's BD architecture is either better or worse than unique. It has resources unlike other CPUs available on the market, and the overall performance level did not meet the needs of many enthusiasts: A Bulldozer The CPU Core differed from a Thuban CPU core or an Intel CPU core from an equivalent core chip. The problem is that they are not nearly different enough to argue that AMD misused the word kernel and the plaintiffs' claims do not stand up to technical analysis.
Consider, for example, the difference between Bulldozer / Piledriver and the Sony Cell Broadband Engine that powered the PS3. No one would argue that Cell was a conventional eight-core processor (19459008) (seven cores were activated for the PS3). It combined a fairly standard PowerPC CPU core (PPE or Power Processing Element) with up to eight SPEs (Synergistic Processing Elements). These SPEs differed significantly from traditional CPU cores, with limited access to small local storage pools and without hardware resources for branch prediction. At RealWorldTech, Deep Dive articles are available to those who are interested in traveling back in time.
Sony did not market the PS3 explicitly as an eight-core system, but according to the most basic definition of the word – the part of the CPU that makes calculations based on received instructions – The SPEs of the Cell Broadband Engine continue to qualify as cores. In this case, Sony recognized this The technical differences between the CBE and other mainstream chips were significant enough to use different labels for the components of the chip. But this acceptance of consumer understanding, although absolutely right for does not mean that we can not call the PES "cores."
Does Bulldozer have an FPU? Certainly. Sun's UltraSPARC T1 (one FPU per chip) and T2 (one FPU per core, but shared by up to eight threads). The lawsuit alleges that the sharing of L2 caches and FPUs means that AMD has violated the well-known definition of "core", while Intel chips have been sharing L2 caches since the Core 2 Duo days. And that's the problem. We could certainly define a CPU core based on the underlying capabilities of the relevant components to function as a Universal Microprocessor without support – something Cell's SPEs can not do. This type of subdivision would make a more meaningful distinction. However, trying to draw a line through a chip in this way is impossible. If bulldozer cores are not cores, they are not cores in other CPUs either.
Unlike Cell every single bulldozer core could perform all the workloads that eight bulldozer cores could perform. Performance was clearly scaled by accessing additional threads, and other CPU designs from other companies that clearly marketed based on the number of cores were available at different levels of performance per core. There is one possible way to draw a clear definition from all of this, but you would not do so with the characteristics put forward by the plaintiffs in this lawsuit.
Dickey and Parmer may be annoyed that they bought eight-core CPUs that did not come along. Not like Intel's eight-core CPUs. That does not mean that Bulldozer was not an eight-core chip. A certain number of cores does not guarantee a given performance.
Now Read :