Products
Adapteva's main product family is the Epiphany scalable multi-core MIMD architecture. The Epiphany architecture could accommodate chips with up to 4,096 RISC out-of-order microprocessors, all sharing a single 32-bit flat memory space. Each RISC processor in the Epiphany architecture is superscalar with 64× 32-bit unified register file (integer or single-precision) microprocessor operating up to 1 GHz and capable of 2 GFLOPS (single-precision). Epiphany's RISC processors use a custom instruction set architecture (ISA) optimised for single-precision floating-point, [4] but are programmable in high level ANSI C using a standard GNU-GCC tool chain. Each RISC processor (in current implementations; not fixed in the architecture) has 32 KB of local memory. Code (possibly duplicated in each core) and stack space should be in that local memory; in addition (most) temporary data should fit there for full speed. Data can also be used from other processor cores local memory at a speed penalty, or off-chip RAM with much larger speed penalty.
The memory architecture does not employ explicit hierarchy of hardware caches, similar to the Sony/Toshiba/IBM Cell processor, but with the additional benefit of off-chip and inter-core loads and stores being supported (which simplifies porting software to the architecture). It is a hardware implementation of partitioned global address space.[ citation needed ]
This eliminated the need for complex cache coherency hardware, which places a practical limit on the number of cores in a traditional multicore system. The design allows the programmer to leverage greater foreknowledge of independent data access patterns to avoid the runtime cost of figuring this out. All processor nodes are connected through a network on chip, allowing efficient message passing. [5]
Scalability
The architecture is designed to scale almost indefinitely, with 4 e-links allowing multiple chips to be combined in a grid topology, allowing for systems with thousands of cores.
Multi-core coprocessors
On August 19, 2012, Adapteva posted some specifications and information about Epiphany multi-core coprocessors. [6]
| Technical info for | E16G301 [7] | E64G401 [8] |
|---|---|---|
| Cores | 16 | 64 |
| Core MHz | 1000 | 800 |
| Core GFLOPS | 2 | 1.6 |
| "Sum GHz" | 16 | 51.2 |
| Sum GFLOPS | 32 | 102 |
| mm² | 8.96 | 8.2 |
| nm | 65 | 28 |
| W def. | 0.9 | 1.4 |
| W max. | 2 | 2 |
In September 2012, a 16-core version, the Epiphany-III (E16G301), was produced using 65 nm [9] (11.5 mm2, 500 MHz chip [10] ) and engineering samples of 64-core Epiphany-IV (E64G401) were produced using 28 nm GlobalFoundries process (800 MHz). [11]
The primary markets for the Epiphany multi-core architecture include:
- Smartphone applications such as real-time facial recognition, speech recognition, translation, and augmented reality.
- Next generation supercomputers requiring drastically better energy efficiency to allow systems to scale to exaflop computing levels.
- Floating-point acceleration in embedded systems based on field-programmable gate array architectures.
Parallella project
In September 2012, Adapteva started project Parallella on Kickstarter, which was marketed as "A Supercomputer for everyone." Architecture reference manuals for the platform were published as part of the campaign to attract attention to the project. [12] The US$750,000 funding goal was reached in a month, with a minimum contribution of US$99 entitling backers to obtain one device; although the initial deadline was set for May 2013, the first single-board computers with 16-core Epiphany chip were finally shipped in December 2013. [13]
Size of board is planned to be 86 mm × 53 mm (3.4 in × 2.1 in). [14] [15] [16]
The Kickstarter campaign raised US$898,921. [17] [18] Raising US$3 million goal was unsuccessful, so no 64-core version of Parallella will be mass-produced. [19] Kickstarter users having donated more than US$750 will get "parallella-64" variant with 64-core coprocessor (made from initial prototype manufacturing with 50 chips yield per wafer). [20]
| Parallella-16 Micro Server | Parallella-16 Desktop Computer | Parallella-16 Embedded Platform | |
|---|---|---|---|
| Usage | Ethernet connected headless server | A personal computer | Leading edge embedded systems |
| Processor | Dual-core 32-bit ARM Cortex-A9 with NEON at 1 GHz (part of Zynq XC7Z010 chip by Xilinx) | Dual-core 32-bit ARM Cortex-A9 with NEON at 1 GHz (part of Zynq XC7Z020 chip by Xilinx) | |
| Coprocessor | 16-core Epiphany III multi-core accelerator (E16) | ||
| Memory | 1 GB DDR3L RAM | ||
| Ethernet | 10/100/1000 | ||
| USB | — | 2× USB 2.0 (USB 2.0 HS and USB OTG) | |
| Display | — | HDMI | |
| Storage | 16 GB microSD | ||
| Expansion | — | 2 eLinks + 24 GPIO | 2 eLinks + 24 GPIO |
| FPGA | 28K programmable logic cells 80 programmable DSP slices | 80K programmable logic cells 220 programmable DSP slices | |
| Weight | 36 g (1.3 oz) | 38 g (1.3 oz) | |
| Size | 3.5 in × 2.1 in × 0.625 in (88.9 mm × 53.3 mm × 15.9 mm) | ||
| SKU | P1600-DK-xx | P1601-DK-xx | P1602-DK-xx |
| HTS Code | 8471.41.0150 | ||
| Power | USB-powered (2.5 W) or 5 V DC (≈5 W) | ||
Epiphany V
By 2016, the firm had taped out a 1024-core 64-bit variant of their Epiphany architecture that featured: larger local stores (64 KB), 64-bit addressing, double-precision floating-point arithmetic or SIMD single-precision, and 64-bit integer instructions, implemented in the 16 nm process node. [21] This design included instruction set enhancements aimed at deep-learning and cryptography applications. In July 2017, Adapteva's founder became a DARPA MTO program manager [22] and announced that the Epiphany V was "unlikely" to become available as a commercial product. [23]
Performance
The 16-core Parallella achieves roughly 5.0 GFLOPS/W, and the 64-core Epiphany-IV made with 28 nm estimated as 50 GFLOPS/W (single-precision), [24] and 32-board system based on them achieves 15 GFLOPS/W. [25] For comparison, top GPUs from AMD and Nvidia reached 10 GFLOPS/W for single-precision in 2009–2011 timeframe. [26]
