Abstract: Systems and methodologies for stall-time fair memory access scheduling for shared memory systems are provided herein. A stall-time fairness policy can be applied in accordance with various aspects described herein to schedule memory requests from threads sharing a memory system. To this end, a Stall-Time Fair Memory scheduler (STFM) algorithm can be utilized, wherein memory-related slowdown experienced by a group of threads due to interference from other threads is equalized. Additionally and/or alternatively, a traditional scheduling policy such as first-ready first-come-first-serve (FR-FCFS) can be utilized in combination with a cap on column-over-row reordering of memory requests, thereby reducing the amount of stall-time unfairness imposed by such traditional scheduling policies. Further, various aspects described herein can perform memory scheduling based on thread weights and/or other parameters, which can be configured in hardware and/or software.

Abstract: Providing for multi-tiered RAM control is provided herein. As an example, a RAM access management system can include multiple input controllers each having a request buffer and request scheduler. Furthermore, a request buffer associated with a controller can vary in size with respect to other buffers. Additionally, request schedulers can vary in complexity and can be optimized at least for a particular request buffer size. As a further example, a first controller can have a large memory buffer and simple scheduling algorithm optimized for scalability. A second controller can have a small memory buffer and a complex scheduler, optimized for efficiency and high RAM performance. Generally, RAM management systems described herein can increase memory system scalability for multi-core parallel processing devices while providing an efficient and high bandwidth RAM interface.

Abstract: Parallelism-aware scheduling of memory requests of threads in shared memory controllers. Parallel scheduling is achieved by prioritizing threads that already have requests being serviced in the memory banks. A first algorithm prioritizes requests of the last-scheduled thread that is currently being serviced. This is accomplished by tracking the thread that generated the last-scheduled request (if the request is still being serviced), and then scheduling another request from the same thread if there is an outstanding ready request from the same thread. A second algorithm prioritizes the requests of all threads that are currently being serviced. This is accomplished by tracking threads that have at least one request currently being serviced in the banks, and assigning the highest priority to these threads in the scheduling decisions. If there are no outstanding requests from any thread having requests that are being serviced, the algorithm defaults back to a baseline scheduling algorithm.

Abstract: Techniques for enhancing throughput capacity and/or bandwidth distribution fairness among APs in a wireless network are described. Specifically, a channel frequency profile which includes a center frequency and channel-width (i.e., channel bandwidth) is dynamically assigned to each of one or more APs in a wireless network. The assigned channel frequency profile for each AP is based, at least in part, on the current composition of the wireless network including, its topology and traffic load distribution. In this regard, each AP's channel frequency profile can be continuously or periodically changed such that the entire available frequency spectrum is effectively utilized and/or interference between APs is avoided or limited. This, in turn, enhances the throughput capacity and/or bandwidth distribution fairness of the wireless network.

Abstract: Architecture for a multi-threaded system that applies fairness to thread memory request scheduling such that access to the shared memory is fair among different threads and applications. A fairness scheduling algorithm provides fair memory access to different threads in multi-core systems, thereby avoiding unfair treatment of individual threads, thread starvation, and performance loss caused by a memory performance hog (MPH) application. The thread slowdown is determined by considering the thread's inherent memory-access characteristics, computed as the ratio of the real latency that the thread experiences and the latency (ideal latency) that the thread would have experienced if it had run as the only thread in the same system. The highest and lowest slowdown values are then used to generate an unfairness parameter which when compared to a threshold value provides a measure of fairness/unfairness currently occurring in the request scheduling process.

Abstract: The described implementations relate to networked or distributed systems and more particularly to providing motivation for deployment of networked systems. One technique gathers a solicitation hierarchy in a distributed system. This technique also tracks contribution to the distributed system of participants within the hierarchy. This technique further probabilistically determines a participant as a lottery winner based at least in part on the solicitation hierarchy and the contribution.

Abstract: A new media access control (MAC) protocol for cognitive wireless networks is described. The new MAC protocol allows each of multiple nodes, such as cell phones and computers with wireless, to determine utilization of a communication spectrum, such as the television broadcast band. The nodes collaborate to achieve a combined view of spectrum utilization in their local vicinity, in which scheduled users and empty time segments are mapped across a wide range of frequencies. Nodes negotiate with each other to reserve idle segments of the spectrum for packet exchange on negotiated frequencies. Control packet structure allows nodes to become prescient of the local spectrum utilization during handshaking. A cognitive device operating under the new MAC has a first radio that both scans the spectrum and monitors a control channel; and a second reconfigurable radio with adjustable parameters, including frequency and bandwidth, for packet transmission.