This paper describes a multi-FPGA based platform for emulating the Loongson-2G micro-processor on different mother boards. This platform is developed targeting at verification and evaluation of the Loongson-2G micro-p...
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ISBN:
(纸本)9781605589114
This paper describes a multi-FPGA based platform for emulating the Loongson-2G micro-processor on different mother boards. This platform is developed targeting at verification and evaluation of the Loongson-2G micro-processor, which is the next generation of Loongson-2 family, composed by one four-issue, out-of-order execution way 64-bit MIPS-compatible processor core named GS464, one 1M byte secondary Cache, one HyperTransport IO interface, one DDR2/3 memory interface and some other low speed IO interfaces. Most parts of this micro-process are mapped into the multi-FPGA based platform which consists two Vertex-5 330 FPGA chips. Semi-custom partitioning tactics within the entire design flow are developed to synthesize the whole designed into the multi-FPGA based platform. Modifications in architectural level are applied to the original architecture of the chip, in order to make it easy to be partitioned into two parts. High speed SEDES of HyperTransport IO link and DDR2/3 memory interface are emulated by using several clocks with different clock phases. To resolve the problem that hard to debug in FPGA system, a method by software probe with help of injected hardware modules in FPGA is developed and used to debug the problem causing by behavior mismatching between the ASIC ram block and the FPGA ram block. Some evaluation work on performance of Loongson-2G is done on this multi-FPGA based platform as pre-silicon test. To the authors' knowledge, there has been no previous work on such a big design used for verification and evaluation.
Submitty is an open-source course management platform for assignment submission with automated testing and grading, immediate feedback with an option for resubmission, and manual grading from course instructors and TA...
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ISBN:
(纸本)9781450358903
Submitty is an open-source course management platform for assignment submission with automated testing and grading, immediate feedback with an option for resubmission, and manual grading from course instructors and TAs. We have added an integrated discussion forum to the Submitty environment, which enables the students to communicate with their peers and have a public dialogue with the teaching staff outside of the classroom. Compared to a collection of closed-source external applications, our single-system login for distribution of course materials, assignment submission, and discussion forum participation is more convenient and accessible for students and simplifies administrative tasks. Students use the forum to ask questions about course logistics, homework help, exam review problems, and Submitty-related questions. The forum supports image and code segment posts, which facilitates targeted debugging help and sharing of additional reference material. An instructor-moderated forum is especially helpful in larger classes where students can feel it is otherwise difficult to get their questions answered. Every thread is tagged with course-specific categories and we provide full-text search of the forum. The forum becomes a curated collection of relevant frequently asked questions, which reduces the number of duplicate questions that must be answered by the staff. The forum includes customizable system and email notifications for important events such as: instructor announcement, assignment posted, team invitation, forum question answered, grades released, etc. Our current work focuses on private channels to facilitate team assignments (which can be monitored for participation by staff) and a grading interface for discussion-based assignments within the forum.
FPGAs have become essential infrastructural components as well as publicly rentable resources in cloud and datacenters. Although one tenant is equipped with a couple of individual physical FPGA devices to solve a sing...
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ISBN:
(纸本)9798400704185
FPGAs have become essential infrastructural components as well as publicly rentable resources in cloud and datacenters. Although one tenant is equipped with a couple of individual physical FPGA devices to solve a single problem, cloud FPGAs are still underutilized in many scenarios. Considering the economic cost of such heterogeneous computing resources, it is essential to explore opportunities for FPGA virtualization such that multiple tenants can share one physical device. Unlike the conventional host-centric virtualization approaches considering FPGAs as I/O peripherals, we propose XUNI, an FPGA-centric and self-contained virtual machine (VM) abstraction without involving the host-side virtualization techniques. Specifically, we design a hardware-software co-designed hypervisor for resource management and provisioning of various FPGA VMs. First, XUNI partitions the FPGA fabric into a series of reconfigurable regions that can be flexibly assembled for the deployment of large-scale designs. Second, we introduce both static partition and dynamic allocation schemes for FPGA-side DRAM sharing in XUNI. Last but not least, a hierarchical multi-tenant hardware network stack is built to provide an I/O interface for each FPGA VM. We implement XUNI and conduct infrastructural evaluations on a custom cloud FPGA node populated with an AMD/Xilinx Zynq MPSoC chip. Preliminary results demonstrate that XUNI is capable of handling hundreds of thousands of FPGA-VM-initiated memory requests per second. The hardware network stack exhibits line rate (~100Gbps) when receiving packets with the default 1500-byte MTU size. Moreover, each FPGA VM boots up within hundreds of milliseconds, which is comparable to emerging lightweight host-side VMs.
Modern massively parallel computers are built from commodity processors and a trend towards commodity interconnects components for Clusters of PCs (CoPs) is visible. Most of today's networking solutions are still ...
ISBN:
(纸本)9780769507835
Modern massively parallel computers are built from commodity processors and a trend towards commodity interconnects components for Clusters of PCs (CoPs) is visible. Most of today's networking solutions are still proprietary, but they do connect to standard buses (i.e. PCI) and in the near future, the networking solutions of the Internet (e.g. Gigabit Ethernet) can offer Gigabit speeds at mass market prices. Cluster platforms like CoPs offer good compute performance, but still they cannot yet utilize the potential of Giga-bit/s communication technology, at least not with commodity network adapters like Ethernet NICs and standard protocols like TCP/IP. While the speed of Ethernet has grown to 1 Gbit/s the functionality and the architectural support in the network interfaces remained the same for more than a decade, so that the memory system becomes a limiting factor. To sustain the raw network speed in applications, a zero-copy network interface architecture would be required, but for all widely used stacks a last copy is required for the (de)fragmentation of the transferred network packets, since Ethernet packets are smaller than a page size. Correctly defragmenting packets of various communication protocols in hardware is an extremely complex task. We therefore consider a speculative defragmentation technique, that can eliminate the last defragmenting copy operation in zero-copy TCP/IP stacks on existing hardware. The payload of fragmented packets is separated from the headers and stored into a memory page that can be mapped directly to its final destination in user memory. For an evaluation of our ideas, we integrated a network interface driver with speculative defragmentation into an existing protocol stack and added well-known page remapping and fast buffer strategies. Measurements indicate that we can improve the performance for Gigabit Ethernet over a standard Linux 2.2 TCP/IP stack by a factor of 1.5-2 for uninterrupted burst transfers. Furthermore, our study
Computational Thinking (CT) has been widely introduced and investigated in recent years, particularly in the U.S. since the born of visual, block-based, drag-drop programming environments such as Kodu, Scratch, Minecr...
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ISBN:
(纸本)9781450336857
Computational Thinking (CT) has been widely introduced and investigated in recent years, particularly in the U.S. since the born of visual, block-based, drag-drop programming environments such as Kodu, Scratch, Minecraft and App Inventor. Although the userinterface is mainly in English, the characteristics of these easy-to-use, game-based, and interactive tools attract many teachers and researchers in the world to pay much attention to the possibilities and opportunities of introducing these tools to students. Recently, some primary school teachers in Hong Kong begin to independently introduce some of these programming tools to students at age 7 - 11 as a part of learning activities in their computer lessons. Their motives are similar but not the same, such as making a fun learning and teaching experience, motivating students for active and collaborative participation, and introducing CT concepts to develop generic skills (e.g. problem solving skills, creativity, and critical thinking). However, there is an absence of well-developed and planned curriculum for "coding education" to introduce computational thinking systematically to students in the local context with expected learning outcomes. Due to the uniqueness of K-12 curriculum in Hong Kong, the existing curriculum model in the U.S. may need to be customized and redesigned to become suitable for integrating into the curriculum in Hong Kong. In this poster, it describes the first proposed coding education curriculum in Hong Kong primary education (Primary 4 to Primary 6) with relevant objectives, structures, contents, and learning outcomes. A new pedagogical design framework for CT is introduced in this poster, which could be generalizable and yet to be evaluated. This new curriculum will serve as the curriculum guide to local teachers, and is the first research initiative of a three-year longitudinal study investigating the impact of CT activities to students particularly in Hong Kong. The experience of this c
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